/* Sensory Academy 视觉系统
 *
 * 与门户页共用同一套令牌：同样的底色、字阶、圆角、阴影与动效，只把强调色
 * 换成紫——门户里 PART 01 Academy 本来就是紫，Core 是青。读者从门户点进来
 * 不会觉得换了一个网站，同时一眼知道自己在哪一半。
 *
 * 令牌名沿用原有的语义名（--ink 是正文色、--paper 是页面底色…），这样
 * 现有 223 处 var() 引用无需逐个改写，改的是它们解析成什么。
 */
:root, :root[data-theme="dark"] {
  color-scheme: dark;

  --ink: #f2f7fc;            /* 正文 */
  --ink-2: #c4d3e6;          /* 次级正文 */
  --muted: #8ba0bd;
  --ink-deep: #f2f7fc;       /* 原为最深色，深色主题下同正文 */

  --paper: #060f1e;          /* 页面底 */
  --foam: #0a1729;           /* 次级面 */
  --card: rgba(255, 255, 255, .035);
  --card-hi: rgba(255, 255, 255, .07);
  --line: rgba(255, 255, 255, .10);
  --line-hi: rgba(255, 255, 255, .20);
  --veil: rgba(255, 255, 255, .028);
  --chip: rgba(255, 255, 255, .045);

  /* 强调色：学院是紫 */
  --accent: #7a5af8;
  --accent-soft: #b9a5ff;
  --mint: #b9a5ff;           /* 旧名保留，指向紫系 */
  --mint-bright: #a78bfa;
  --on-accent: #ffffff;

  --teal: #2dd4bf;           /* 指向 Core 的地方仍用青 */
  --coral: #f97066;
  --sun: #f79009;
  --green: #12b76a;

  --shadow: 0 26px 60px -30px rgba(0, 0, 0, .9);
  --r: 18px;
  --shell: clamp(20px, 6vw, 96px);
  --ease: cubic-bezier(.22, .61, .36, 1);
  --aurora-a: .5;

  font-family: "PingFang SC", "HarmonyOS Sans SC", "Microsoft YaHei",
               system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  color: var(--ink);
  background: var(--paper);
}

/* 浅色：与门户同一套做法——另配一套，不是把深色反相。强调色压深一档，
   否则紫色在白底上发飘、对比度不够。 */
:root[data-theme="light"] {
  color-scheme: light;

  --ink: #0d1b2a;
  --ink-2: #3c516b;
  --muted: #64788f;
  --ink-deep: #0d1b2a;

  --paper: #f7f9fc;
  --foam: #ffffff;
  --card: rgba(13, 27, 42, .028);
  --card-hi: rgba(13, 27, 42, .055);
  --line: rgba(13, 27, 42, .12);
  --line-hi: rgba(13, 27, 42, .24);
  --veil: rgba(13, 27, 42, .04);
  --chip: rgba(13, 27, 42, .04);

  --accent: #6d28d9;
  --accent-soft: #6d28d9;
  --mint: #6d28d9;
  --mint-bright: #5b21b6;
  --on-accent: #ffffff;

  --teal: #0f766e;
  --coral: #b91c1c;
  --sun: #a4530a;
  --green: #15803d;

  --shadow: 0 22px 50px -30px rgba(13, 27, 42, .35);
  --aurora-a: .28;
}

@media (prefers-color-scheme: light) {
  :root:not([data-theme="dark"]) {
    color-scheme: light;
    --ink: #0d1b2a; --ink-2: #3c516b; --muted: #64788f; --ink-deep: #0d1b2a;
    --paper: #f7f9fc; --foam: #ffffff;
    --card: rgba(13, 27, 42, .028); --card-hi: rgba(13, 27, 42, .055);
    --line: rgba(13, 27, 42, .12); --line-hi: rgba(13, 27, 42, .24);
    --veil: rgba(13, 27, 42, .04); --chip: rgba(13, 27, 42, .04);
    --accent: #6d28d9; --accent-soft: #6d28d9;
    --mint: #6d28d9; --mint-bright: #5b21b6;
    --teal: #0f766e; --coral: #b91c1c; --sun: #a4530a; --green: #15803d;
    --shadow: 0 22px 50px -30px rgba(13, 27, 42, .35);
    --aurora-a: .28;
  }
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body { margin: 0; min-width: 320px; background: var(--paper); }
button, input { font: inherit; }
button { cursor: pointer; }
button:focus-visible, a:focus-visible, input:focus-visible { outline: 3px solid var(--sun); outline-offset: 3px; }
.skip-link { position: fixed; top: 10px; left: 10px; z-index: 100; padding: 10px 14px; transform: translateY(-150%); background: var(--foam); color: var(--ink); border-radius: 4px; }
.skip-link:focus { transform: translateY(0); }
.site-header { position: sticky; top: 0; z-index: 20; display: flex; align-items: center; justify-content: space-between; min-height: 72px; padding: 12px clamp(22px, 5vw, 76px); border-bottom: 1px solid var(--line); background: color-mix(in srgb, var(--paper) 86%, transparent); backdrop-filter: blur(16px); }
.brand { display: inline-flex; align-items: center; color: var(--ink); text-decoration: none; }
.brand img { display: block; width: clamp(190px, 20vw, 250px); height: 46px; object-fit: contain; object-position: left center; }
.header-tools { min-width: 0; display: flex; align-items: center; gap: clamp(16px, 2vw, 28px); }
nav { display: flex; gap: clamp(14px, 2.6vw, 35px); }
.academy-nav-panel { display: contents; }
nav a { color: var(--ink-2); font-size: 13px; text-decoration: none; }
nav a:hover { color: var(--mint-bright); }
.platform-home { min-height: 34px; margin-left: clamp(6px, 1.2vw, 14px); padding-left: clamp(14px, 1.8vw, 22px); display: inline-flex; align-items: center; gap: 7px; color: var(--ink); border-left: 1px solid var(--line-hi); font-size: 13px; font-weight: 700; text-decoration: none; white-space: nowrap; }
.platform-home span { color: var(--mint-bright); font-size: 18px; line-height: 1; }
.platform-home b { font-weight: 700; }
.platform-home:hover { color: var(--mint-bright); }
.language-toggle { min-height: 34px; width: 42px; padding: 0; border: 1px solid var(--line-hi); border-radius: 19px; display: inline-flex; align-items: center; justify-content: center; background: transparent; color: var(--ink-2); font: 800 11px/1 system-ui, -apple-system, "Segoe UI", sans-serif; letter-spacing: 0; }
.language-toggle:hover { color: var(--mint-bright); border-color: color-mix(in srgb, var(--accent) 50%, transparent); }
.academy-menu-toggle { display: none; }
.section-wrap { width: min(1180px, calc(100% - 48px)); margin-inline: auto; }
.hero { position: relative; isolation: isolate; display: grid; grid-template-columns: minmax(0, 1.16fr) minmax(350px, .84fr); min-height: 660px; overflow: hidden; padding: clamp(64px, 9vw, 130px) max(24px, calc((100vw - 1180px) / 2)); color: var(--ink); background: radial-gradient(circle at 78% 37%, color-mix(in srgb, var(--accent) 32%, transparent), transparent 23%), radial-gradient(circle at 15% 90%, color-mix(in srgb, var(--coral) 20%, transparent), transparent 32%), var(--ink-deep); }
.hero-grid { position: absolute; z-index: -2; inset: 0; opacity: .35; background-image: linear-gradient(var(--veil) 1px, transparent 1px), linear-gradient(90deg, var(--veil) 1px, transparent 1px); background-size: 48px 48px; mask-image: radial-gradient(ellipse at 70% 45%, #000 20%, transparent 70%); animation: drift-grid 20s linear infinite; }
.hero-signal { position: absolute; z-index: -1; width: 600px; height: 600px; border: 1px solid var(--line-hi); border-radius: 50%; pointer-events: none; }
.signal-one { right: -180px; top: 10px; animation: breathe 6s ease-in-out infinite; }
.signal-two { right: -40px; top: 130px; width: 360px; height: 360px; border-color: color-mix(in srgb, var(--coral) 26%, transparent); animation: breathe 6s 1s ease-in-out infinite reverse; }
.hero-copy-wrap { align-self: center; max-width: 660px; }
.eyebrow { margin: 0 0 14px; color: var(--mint-bright); font-size: 11px; font-weight: 800; letter-spacing: .18em; }
.eyebrow.ink { color: var(--accent); }
.eyebrow.mint { color: var(--mint-bright); }
h1, h2, h3, p { margin-top: 0; }
h1 { margin-bottom: 22px; font-size: clamp(40px, 4.2vw, 58px); line-height: 1.12; letter-spacing: 0; }
.mobile-title-break { display: none; }
h1 em { color: var(--mint-bright); font-style: normal; }
.hero-copy { max-width: 600px; color: var(--ink-2); font-size: 17px; line-height: 1.8; }
.hero-actions { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 32px; }
.button { display: inline-flex; align-items: center; justify-content: center; min-height: 48px; padding: 0 20px; border: 1px solid transparent; border-radius: 5px; font-weight: 700; text-decoration: none; transition: transform .24s ease, background .24s ease; }
.button:hover { transform: translateY(-2px); }
.button-primary { gap: 10px; color: var(--ink-deep); background: var(--mint-bright); }
.button-quiet { color: var(--ink); border-color: var(--muted); }
.hero-metrics { display: flex; flex-wrap: wrap; gap: 22px 28px; margin-top: 54px; color: var(--ink-2); font-size: 12px; }
.hero-metrics span { display: grid; gap: 5px; }
.hero-metrics b { color: var(--sun); font-size: 23px; font-weight: 700; }
.hero-orbit { position: relative; align-self: center; justify-self: center; width: min(38vw, 455px); aspect-ratio: 1; }
.orbit-ring { position: absolute; inset: 7%; border: 1px solid rgba(179, 243, 212, .35); border-radius: 50%; }
.orbit-ring-a { animation: spin 26s linear infinite; }
.orbit-ring-b { inset: 17%; border-style: dashed; border-color: color-mix(in srgb, var(--sun) 58%, transparent); animation: spin 16s linear infinite reverse; }
.orbit-core { position: absolute; inset: 36%; display: grid; place-content: center; border-radius: 50%; color: var(--mint-bright); text-align: center; background: var(--card-hi); box-shadow: inset 0 0 30px rgba(126, 230, 188, .24), 0 0 80px rgba(126, 230, 188, .12); }
.orbit-core span { font-size: 8px; font-weight: 800; letter-spacing: .2em; }
.orbit-core b { color: var(--ink); font-size: 36px; line-height: 1.05; }
.orbit-node { position: absolute; display: flex; align-items: center; gap: 8px; color: var(--ink-2); font-size: 12px; font-weight: 700; }
.orbit-node i { width: 10px; height: 10px; border-radius: 50%; background: var(--mint-bright); box-shadow: 0 0 14px var(--mint-bright); }
.node-a { top: 3%; left: 36%; }.node-b { right: 0; top: 46%; }.node-c { bottom: 4%; left: 37%; }.node-d { top: 46%; left: -3%; }.node-c i { background: var(--sun); box-shadow: 0 0 14px var(--sun); }.node-d i { background: var(--coral); box-shadow: 0 0 14px var(--coral); }
.path-section { padding-block: 120px; }
.section-heading { max-width: 720px; }
.section-heading h2, .course-nav h2, .closing h2 { margin-bottom: 14px; font-size: clamp(31px, 4vw, 48px); line-height: 1.18; }
.section-heading > p:last-child, .course-nav > p, .closing > p:last-child { color: var(--muted); line-height: 1.8; }
.path-steps { display: grid; grid-template-columns: repeat(4, 1fr); gap: 0; margin: 50px 0 0; padding: 0; list-style: none; border-top: 1px solid var(--line); }
.path-steps li { position: relative; padding: 24px 30px 0 0; border-right: 1px solid var(--line); }
.path-steps li:not(:first-child) { padding-left: 28px; }.path-steps li:last-child { border: 0; }
.path-steps span { display: block; margin-bottom: 22px; color: var(--coral); font-size: 12px; font-weight: 800; letter-spacing: .12em; }.path-steps b { font-size: 21px; }.path-steps p { max-width: 270px; margin: 12px 0 0; color: var(--muted); font-size: 14px; line-height: 1.75; }
.lexicon-section { position: relative; overflow: hidden; padding: 104px 0; color: var(--ink); background: var(--paper); }
.lexicon-section::before { position: absolute; inset: 0; content: ""; pointer-events: none; opacity: .42; background-image: linear-gradient(color-mix(in srgb, var(--accent) 10%, transparent) 1px, transparent 1px), linear-gradient(90deg, color-mix(in srgb, var(--accent) 10%, transparent) 1px, transparent 1px); background-size: 46px 46px; mask-image: linear-gradient(90deg, transparent, #000 52%, transparent); }
.lexicon-layout { position: relative; display: grid; grid-template-columns: minmax(320px, .72fr) minmax(0, 1.28fr); align-items: center; gap: clamp(42px, 6vw, 82px); }
.lexicon-copy h2 { margin-bottom: 18px; font-size: clamp(32px, 4vw, 50px); line-height: 1.16; }
.lexicon-copy > p:not(.eyebrow):not(.lexicon-source-note) { color: var(--ink-2); line-height: 1.85; }
.lexicon-metrics { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 12px; margin: 34px 0; padding: 19px 0; border-top: 1px solid var(--line-hi); border-bottom: 1px solid var(--line-hi); }
.lexicon-metrics span { display: grid; gap: 5px; color: var(--muted); font-size: 10px; }
.lexicon-metrics b { color: var(--sun); font-size: 22px; }
.lexicon-button { width: max-content; }
.lexicon-source-note { margin: 18px 0 0; color: var(--muted); font-size: 10px; line-height: 1.65; }
.lexicon-preview { position: relative; display: block; min-width: 0; aspect-ratio: 16 / 10; overflow: hidden; color: var(--ink); border: 1px solid var(--ink-2); background: var(--foam); box-shadow: 0 26px 70px rgba(0,0,0,.3); text-decoration: none; }
.lexicon-preview::after { position: absolute; inset: 0; content: ""; pointer-events: none; border: 1px solid transparent; transition: border-color .25s ease; }
.lexicon-preview:hover::after { border-color: var(--mint-bright); }
.lexicon-preview img { display: block; width: 100%; height: 100%; object-fit: cover; object-position: center; transition: transform .55s ease; }
.lexicon-preview:hover img { transform: scale(1.025); }
.lexicon-preview span { position: absolute; right: 18px; bottom: 14px; left: 18px; display: grid; grid-template-columns: auto 1fr auto; align-items: center; gap: 10px; padding: 9px 11px; color: var(--muted); font-size: 8px; font-weight: 800; background: color-mix(in srgb, var(--paper) 82%, transparent); backdrop-filter: blur(8px); }
.lexicon-preview i { height: 1px; background: linear-gradient(90deg, var(--accent-soft), #ff7969); }
.labs-section { padding: 104px 0 120px; color: var(--ink); background: var(--foam); }
.labs-section .section-heading > p:last-child { color: var(--ink-2); }
.lab { position: relative; display: grid; grid-template-columns: 180px minmax(0, 1fr); gap: 24px 36px; margin-top: 42px; padding: 34px; overflow: hidden; border: 1px solid var(--card-hi); background: var(--card); box-shadow: 0 16px 35px rgba(0,0,0,.12); }
.lab::after { position: absolute; top: 0; right: 0; width: 160px; height: 1px; content: ""; background: var(--mint-bright); }
.lab-label { display: grid; align-content: start; gap: 8px; color: var(--mint-bright); font-size: 11px; font-weight: 800; letter-spacing: .13em; }.lab-label i { color: var(--muted); font-size: 9px; font-style: normal; }.lab-intro { max-width: 720px; }.lab-intro h3 { margin-bottom: 8px; font-size: 27px; }.lab-intro p { margin-bottom: 0; color: var(--ink-2); line-height: 1.75; }
.matcher-options, .matcher-map-2d, .matcher-result, .method-space, .mode-switch, .cup-row, .lab-feedback, .lab-footer, .control-line, .lab-footer-controls, .sequence-key, .williams-grid, .order-space, .lab-note, .pca-layout, .lab-controls, .lab-canvas-wrap, .lab-readout { grid-column: 2; }
.matcher-options { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 9px; }.question-option { display: flex; align-items: center; gap: 12px; min-height: 62px; padding: 12px 15px; color: var(--ink-2); text-align: left; border: 1px solid var(--line-hi); border-radius: 4px; background: transparent; transition: border .2s, background .2s, transform .2s; }.question-option:hover, .question-option.active { border-color: var(--mint-bright); background: color-mix(in srgb, var(--accent) 14%, transparent); }.question-option:hover { transform: translateY(-2px); }.question-option span { color: var(--sun); font-size: 11px; font-weight: 800; }
.matcher-result { display: grid; grid-template-columns: 175px 1fr; gap: 22px; padding: 20px; border-left: 3px solid var(--coral); background: var(--line-hi); }.matcher-result h4 { margin: 0; color: var(--sun); font-size: 21px; }.matcher-result p { margin: 0; color: var(--ink-2); line-height: 1.75; }.matcher-result small { display: block; margin-top: 8px; color: var(--mint-bright); }
.method-space, .order-space { position: relative; display: none; min-height: 260px; overflow: hidden; background: radial-gradient(circle at 50% 50%, rgba(126,227,189,.16), transparent 45%), var(--line-hi); transform: perspective(1000px) translateY(-16px) scale(.96); opacity: 0; }.method-space.active, .order-space.active { display: block; animation: space-dive .72s cubic-bezier(.18,.82,.28,1) forwards; }.method-canvas, .order-canvas { position: absolute; inset: 0; width: 100%; height: 100%; cursor: grab; touch-action: none; }.method-canvas:active, .order-canvas:active { cursor: grabbing; }.method-space::before, .order-space::before { position: absolute; inset: 0; content: ""; pointer-events: none; background: linear-gradient(90deg, var(--card-hi) 1px, transparent 1px), linear-gradient(var(--card-hi) 1px, transparent 1px); background-size: 34px 34px; mask-image: radial-gradient(ellipse at center, #000 8%, transparent 68%); }.method-space-copy, .order-space-copy { position: absolute; z-index: 1; top: 16px; left: 18px; display: grid; gap: 4px; max-width: 280px; pointer-events: none; }.method-space-copy span, .order-space-copy span { color: var(--mint-bright); font-size: 9px; font-weight: 800; letter-spacing: .16em; }.method-space-copy b, .order-space-copy b { color: var(--ink-2); font-size: 14px; }.method-space-copy small { color: var(--muted); font-size: 10px; }.order-space-copy { top: auto; bottom: 16px; }.order-space-copy b { max-width: 220px; font-size: 13px; }
.mode-switch { display: inline-flex; justify-self: start; padding: 4px; border: 1px solid var(--ink-2); border-radius: 5px; }.mode-button { min-height: 34px; padding: 0 14px; color: var(--ink-2); border: 0; border-radius: 3px; background: transparent; }.mode-button.active { color: var(--ink-deep); font-weight: 800; background: var(--mint-bright); }
.cup-row { display: flex; justify-content: center; gap: clamp(18px, 6vw, 74px); padding: 15px 10px 3px; }.cup { position: relative; display: grid; place-items: center; width: 105px; height: 112px; padding-top: 17px; color: var(--ink-deep); font-size: 17px; font-weight: 800; letter-spacing: .08em; border: 0; clip-path: polygon(11% 0, 89% 0, 100% 100%, 0 100%); background: var(--card); transition: transform .22s, filter .22s; }.cup::before { position: absolute; top: 9px; width: 75%; height: 14px; content: ""; border-radius: 50%; background: #a38167; }.cup:hover, .cup.selected { transform: translateY(-8px); filter: drop-shadow(0 12px 10px rgba(0,0,0,.28)); }.cup.selected { outline: 3px solid var(--sun); }.cup b { z-index: 1; margin-top: 23px; }.cup small { z-index: 1; margin-top: -14px; color: var(--muted); font-size: 10px; letter-spacing: 0; }
.lab-feedback { min-height: 51px; padding: 15px 17px; color: var(--ink-2); line-height: 1.65; border: 1px solid var(--card-hi); background: var(--line-hi); }.lab-feedback.correct { color: #e8ff9f; border-color: var(--ink-2); }.lab-feedback.incorrect { color: #ffb0a5; border-color: color-mix(in srgb, var(--coral) 55%, transparent); }.lab-footer { display: flex; align-items: center; justify-content: space-between; gap: 16px; color: var(--muted); font-size: 12px; }.text-button { padding: 0; color: var(--mint-bright); border: 0; border-bottom: 1px solid currentColor; background: transparent; }
.control-line { display: grid; grid-template-columns: 130px minmax(160px, 1fr) 38px; align-items: center; gap: 16px; }.control-line label { color: var(--ink-2); font-size: 14px; }.control-line output { display: inline-grid; min-width: 23px; place-items: center; margin-left: 5px; color: var(--ink-deep); font-weight: 800; background: var(--sun); }.control-line input { accent-color: var(--mint-bright); }.icon-button { display: grid; place-items: center; width: 38px; height: 38px; color: var(--ink-deep); border: 0; border-radius: 50%; background: var(--mint-bright); }
.sequence-key { display: flex; flex-wrap: wrap; gap: 8px; }.sequence-key span { display: none; width: 24px; height: 24px; place-items: center; color: var(--ink-deep); font-size: 11px; font-weight: 800; border-radius: 50%; }.sequence-key span:nth-child(-n + 4) { display: grid; }.sample-a { background: #d8f4a3; }.sample-b { background: #ffbfaa; }.sample-c { background: var(--accent-soft); }.sample-d { background: #f5dc7c; }.sample-e { background: #d8b9f4; }.sample-f { background: #f2a7c7; }.sample-g { background: #bde4bc; }.sample-h { background: #c1cdf5; }
.williams-grid { display: grid; grid-template-columns: minmax(90px, 1fr) repeat(var(--sample-count, 4), minmax(38px, .65fr)); gap: 6px; max-width: 650px; }.grid-head, .grid-label, .grid-cell { display: grid; min-height: 35px; place-items: center; font-size: 12px; }.grid-head, .grid-label { color: var(--ink-2); }.grid-cell { color: var(--ink-deep); font-weight: 800; border-radius: 3px; transition: transform .2s, opacity .2s; }.grid-cell.pulse { transform: scale(1.08); box-shadow: 0 0 0 2px var(--sun); }
.lab-note { margin: 0; color: var(--ink-2); font-size: 13px; line-height: 1.7; }
.pca-layout { display: grid; grid-template-columns: minmax(390px, 1.15fr) minmax(245px, .65fr); align-items: stretch; gap: 28px; }
.pca-scene-wrap { position: relative; min-height: 390px; overflow: hidden; background: radial-gradient(circle at 50% 46%, color-mix(in srgb, var(--accent) 19%, transparent), transparent 30%), linear-gradient(138deg, rgba(0,0,0,.22), transparent 68%); }
.pca-scene-wrap::before { position: absolute; inset: 0; content: ""; pointer-events: none; opacity: .45; background-image: linear-gradient(var(--card) 1px, transparent 1px), linear-gradient(90deg, var(--card) 1px, transparent 1px); background-size: 36px 36px; mask-image: radial-gradient(circle at 50% 50%, #000 12%, transparent 72%); }
.pca-canvas { position: absolute; inset: 0; width: 100%; height: 100%; cursor: grab; touch-action: none; }.pca-canvas:active { cursor: grabbing; }
.pca-scene-hud { position: absolute; top: 18px; left: 18px; display: grid; gap: 4px; color: var(--muted); font-size: 10px; font-weight: 800; letter-spacing: .1em; pointer-events: none; }.pca-scene-hud span:first-child { color: var(--mint-bright); }
.pca-view-controls { position: absolute; right: 16px; bottom: 16px; display: flex; flex-wrap: wrap; justify-content: flex-end; gap: 5px; max-width: 270px; }.pca-view-button, .pca-reset { min-height: 32px; padding: 0 10px; color: var(--ink-2); font-size: 11px; border: 1px solid var(--ink-2); border-radius: 3px; background: rgba(3,47,45,.69); backdrop-filter: blur(6px); }.pca-view-button.active { color: var(--ink-deep); font-weight: 800; border-color: var(--mint-bright); background: var(--mint-bright); }.pca-reset { width: 32px; padding: 0; color: var(--sun); font-size: 17px; }
.pca-sidecar { display: grid; grid-template-rows: auto 1fr; gap: 15px; }.pca-pills { display: flex; flex-wrap: wrap; gap: 6px; }.pca-pill { min-height: 29px; padding: 0 9px; color: var(--ink-2); font-size: 11px; border: 1px solid var(--ink-2); border-radius: 14px; background: var(--line-hi); }.pca-pill.attribute { color: var(--sun); }.pca-pill:hover, .pca-pill.active { color: var(--ink-deep); border-color: var(--mint-bright); background: var(--mint-bright); }
.pca-insight { display: grid; align-content: center; min-height: 230px; padding: 25px; border-left: 3px solid var(--sun); background: var(--line-hi); }.pca-insight h4 { margin-bottom: 10px; color: var(--mint-bright); font-size: 22px; }.pca-insight p { margin: 0; color: var(--ink-2); line-height: 1.75; }
.pca-fallback { display: grid; min-height: 260px; place-items: center; margin: 0; padding: 24px; color: var(--ink-2); text-align: center; line-height: 1.7; background: var(--line-hi); }
.sr-only { position: absolute; width: 1px; height: 1px; padding: 0; overflow: hidden; clip: rect(0,0,0,0); white-space: nowrap; border: 0; }
.toolkit-section { padding-block: 120px; }
.toolkit-tabs { display: inline-flex; flex-wrap: wrap; gap: 6px; margin: 34px 0 16px; padding: 5px; border: 1px solid var(--line); border-radius: 5px; background: var(--foam); }
.toolkit-tab { min-height: 38px; padding: 0 16px; color: var(--muted); border: 0; border-radius: 3px; background: transparent; }
.toolkit-tab.active { color: var(--on-accent); font-weight: 800; background: var(--accent); border-color: transparent; }
.toolkit-status { min-height: 26px; color: var(--muted); font-size: 13px; }
.resource-strip { display: flex; flex-wrap: wrap; gap: 9px; margin-top: 12px; }
.resource-strip a, .lesson-resources a, .download-link { display: inline-flex; align-items: center; justify-content: center; min-height: 34px; padding: 0 12px; color: var(--ink); font-size: 12px; font-weight: 800; text-decoration: none; border: 1px solid var(--line); border-radius: 3px; background: var(--foam); }
.resource-strip a:hover, .lesson-resources a:hover, .download-link:hover { border-color: var(--ink); }
.toolkit-panel { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 18px; margin-top: 18px; }
.toolkit-panel[hidden] { display: none !important; }
.case-level-heading { grid-column: 1 / -1; display: flex; align-items: end; justify-content: space-between; gap: 24px; margin-top: 22px; padding: 18px 0 10px; border-bottom: 2px solid var(--line-hi); }
.case-level-heading:first-child { margin-top: 0; }
.case-level-heading h3, .case-level-heading p { margin: 0; }
.case-level-heading h3 { font-size: 22px; }
.case-level-heading p { max-width: 560px; color: var(--muted); font-size: 13px; text-align: right; }
.case-level-heading.level-start { border-color: var(--mint-bright); }
.case-level-heading.level-build { border-color: var(--sun); }
.case-level-heading.level-advanced { border-color: var(--coral); }
.toolkit-card { display: grid; align-content: start; gap: 12px; min-height: 280px; padding: 24px; border: 1px solid var(--line); background: var(--foam); box-shadow: 0 12px 30px rgba(2,44,41,.06); }
.toolkit-card h3 { margin-bottom: 0; font-size: 22px; line-height: 1.28; }
.toolkit-card p, .toolkit-card small { margin: 0; color: var(--muted); line-height: 1.7; }
.toolkit-card b { color: var(--ink); font-size: 14px; line-height: 1.65; }
.toolkit-label { justify-self: start; padding: 4px 8px; color: var(--ink-deep); font-size: 11px; font-weight: 800; letter-spacing: .1em; background: var(--mint); }
.toolkit-actions { display: flex; flex-wrap: wrap; gap: 8px; }
.copy-button { justify-self: start; min-height: 36px; padding: 0 13px; color: var(--ink); border: 0; border-radius: 3px; background: var(--coral); }
.template-preview { max-height: 142px; margin: 0; overflow: auto; padding: 13px; color: rgba(7,61,58,.82); font-size: 12px; line-height: 1.65; white-space: pre-wrap; border: 1px solid var(--line); background: var(--foam); }
.toolkit-card .takeaway { padding-top: 12px; color: var(--ink); border-top: 1px solid var(--line); }
.toolkit-card .wrong { padding-left: 13px; border-left: 3px solid var(--coral); }
.toolkit-card .fix { padding-left: 13px; color: var(--ink); border-left: 3px solid var(--mint-bright); }
.mistakes-progress { grid-column: 1 / -1; margin: 0 0 4px; color: var(--muted); font-size: 13px; font-weight: 700; }
/* 国家标准索引面板 */
.standards-intro { grid-column: 1 / -1; margin: 0 0 6px; color: var(--muted); font-size: 13px; line-height: 1.75; }
.standards-group-heading { grid-column: 1 / -1; margin: 14px 0 2px; font-size: 16px; }
.standard-card { min-height: auto; gap: 8px; }
.standard-code { margin: 0; color: var(--ink); font-size: 17px; letter-spacing: .02em; }
.standard-title { margin: 0; color: var(--ink); font-size: 15px; font-weight: 700; line-height: 1.5; }
.standard-title-en { color: var(--muted); font-size: 11px; font-style: italic; line-height: 1.5; }
.standard-meta { color: var(--muted); font-size: 11px; }
.standard-scope { margin: 0; padding-top: 8px; border-top: 1px solid var(--line); }
.standard-file-note { margin: 0; padding: 8px 10px; color: var(--ink); font-size: 12px; background: #fff6e5; border-left: 3px solid var(--sun); }
.standard-method .toolkit-label { background: var(--mint); }
.standard-product .toolkit-label { background: #ffe8c9; }
.mistake-card { min-height: auto; }
.mistake-prompt { color: var(--ink); font-weight: 700; }
.mistake-options button { min-height: auto; padding: 12px 14px; line-height: 1.6; white-space: normal; }
.mistake-feedback { display: grid; gap: 8px; margin-top: 4px; }
.mistake-feedback.correct { color: var(--ink-deep); border-color: color-mix(in srgb, var(--accent) 50%, transparent); background: var(--card-hi); }
.mistake-feedback.incorrect { border-color: rgba(244,111,94,.4); background: color-mix(in srgb, var(--coral) 14%, var(--foam)); }
.mistake-feedback p { margin: 0; }
.quiz-section {
  --quiz-copy: #f2f7fc;
  --quiz-copy-muted: #c4d3e6;
  --quiz-level-accent: #c8b5ff;
  padding: 108px 0; color: var(--quiz-copy);
  transition: background .38s var(--ease);
}
.quiz-section[data-quiz-level="start"] {
  --quiz-level-accent: #5ee0b0;
  background: linear-gradient(132deg, #17352f 0%, #214b42 58%, #182c3d 100%);
}
.quiz-section[data-quiz-level="build"] {
  background: linear-gradient(132deg, #171d3a 0%, #382860 58%, #18243b 100%);
}
.quiz-section[data-quiz-level="advanced"] {
  --quiz-level-accent: #ff9c91;
  background: linear-gradient(132deg, #080d19 0%, #211334 58%, #080f1e 100%);
}
.quiz-layout { display: grid; grid-template-columns: minmax(260px, .7fr) minmax(0, 1.3fr); align-items: start; gap: 50px; }
.quiz-copy h2 { margin-bottom: 14px; font-size: clamp(31px, 4vw, 48px); line-height: 1.18; }
.quiz-copy p:not(.eyebrow) { color: var(--quiz-copy-muted); line-height: 1.8; }
.quiz-copy .quiz-level-note { margin: -4px 0 16px; color: var(--quiz-copy-muted); font-size: 13px; font-weight: 700; }
.quiz-meter { position: relative; height: 36px; margin-top: 30px; overflow: hidden; border: 1px solid var(--quiz-copy-muted); }
.quiz-meter span { position: relative; z-index: 1; display: grid; height: 100%; place-items: center start; padding-left: 12px; color: var(--quiz-copy-muted); font-size: 12px; font-weight: 800; }
.quiz-meter i { position: absolute; inset: 0 auto 0 0; width: 10%; background: color-mix(in srgb, var(--quiz-level-accent) 38%, transparent); transition: width .28s ease; }
.quiz-section .quiz-card { min-height: 430px; padding: 30px; color: var(--ink); background: var(--paper); box-shadow: var(--shadow); }
.quiz-topic { display: inline-grid; margin-bottom: 16px; padding: 5px 9px; color: var(--ink-deep); font-size: 11px; font-weight: 800; letter-spacing: .1em; background: var(--sun); }
.quiz-card h3 { min-height: 74px; margin-bottom: 20px; font-size: clamp(22px, 2.8vw, 32px); line-height: 1.35; }
.quiz-options { display: grid; gap: 10px; }
.quiz-options button { min-height: 52px; padding: 12px 14px; color: var(--ink); text-align: left; border: 1px solid var(--line); border-radius: 4px; background: var(--foam); }
.quiz-options button:hover { border-color: var(--ink); }
.quiz-options button.correct { color: var(--ink-deep); border-color: var(--mint-bright); background: var(--card-hi); }
.quiz-options button.incorrect { border-color: var(--coral); background: color-mix(in srgb, var(--coral) 14%, var(--foam)); }
.quiz-options button:disabled { cursor: default; }
.quiz-feedback { min-height: 64px; margin-top: 18px; padding: 15px; color: var(--muted); line-height: 1.7; border: 1px solid var(--line); background: var(--foam); }
.quiz-feedback.correct { color: var(--accent); border-color: rgba(10,108,96,.3); background: #ecfbf3; }
.quiz-feedback.incorrect { color: var(--coral); border-color: rgba(244,111,94,.35); background: #fff4f0; }
.quiz-actions { display: flex; justify-content: space-between; gap: 12px; margin-top: 18px; }
.quiz-actions button { min-height: 40px; padding: 0 15px; color: var(--ink); border: 1px solid var(--line); border-radius: 3px; background: transparent; }
.quiz-certificate-guide { grid-column: 1 / -1; margin-top: 4px; border: 1px solid var(--ink-2); background: rgba(2,42,40,.32); }
.quiz-certificate-guide summary { display: flex; align-items: center; gap: 18px; min-height: 58px; padding: 12px 18px; cursor: pointer; list-style: none; }
.quiz-certificate-guide summary::-webkit-details-marker { display: none; }
.quiz-certificate-guide summary::after { content: "+"; margin-left: auto; color: var(--mint-bright); font-size: 24px; font-weight: 300; line-height: 1; }
.quiz-certificate-guide[open] summary::after { content: "−"; }
.quiz-certificate-guide summary:focus-visible { outline: 3px solid var(--sun); outline-offset: 3px; }
.quiz-certificate-guide summary span { font-weight: 800; }
.quiz-certificate-guide summary small { color: var(--ink-2); font-size: 12px; }
.quiz-certificate-content { display: grid; grid-template-columns: minmax(260px, .72fr) minmax(0, 1.28fr); gap: 32px; padding: 24px; border-top: 1px solid var(--line-hi); background: #f5faf8; color: var(--ink); }
.quiz-grade-rules h3 { margin-bottom: 16px; font-size: 24px; }
.quiz-grade-rules table { width: 100%; margin-bottom: 18px; border-collapse: collapse; font-size: 13px; }
.quiz-grade-rules th, .quiz-grade-rules td { padding: 9px 10px; text-align: left; border-bottom: 1px solid var(--line); }
.quiz-grade-rules th { color: var(--muted); font-size: 11px; }
.quiz-grade-rules p:not(.eyebrow) { margin: 12px 0 0; color: var(--muted); font-size: 13px; line-height: 1.75; }
.quiz-grade-rules .quiz-certificate-boundary { padding-left: 11px; color: var(--ink); border-left: 3px solid var(--coral); }
.quiz-certificate-preview { margin: 0; }
.quiz-certificate-preview a { display: block; cursor: zoom-in; }
.quiz-certificate-preview img { display: block; width: 100%; height: auto; aspect-ratio: 3 / 2; object-fit: contain; background: var(--foam); box-shadow: 0 18px 42px rgba(6,48,44,.16); }
.quiz-certificate-preview figcaption { margin-top: 10px; color: var(--muted); font-size: 11px; text-align: right; }
.system-section { padding-block: 115px; }
.system-map { display: grid; grid-template-columns: repeat(4, 1fr); gap: 0; margin-top: 42px; border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); }
.system-map div { min-height: 178px; padding: 24px 22px; border-right: 1px solid var(--line); }
.system-map div:last-child { border-right: 0; }
.system-map span { display: block; margin-bottom: 20px; color: var(--coral); font-size: 12px; font-weight: 800; letter-spacing: .12em; }
.system-map b { display: block; margin-bottom: 9px; font-size: 21px; }
.system-map p { margin: 0; color: var(--muted); line-height: 1.7; }
.course-section { padding: 120px 0; background: var(--foam); }.course-layout { display: grid; grid-template-columns: 310px minmax(0, 1fr); gap: 56px; }.course-nav { align-self: start; position: sticky; top: 96px; }.lesson-list { display: grid; gap: 5px; margin-top: 30px; }.lesson-list button { display: grid; grid-template-columns: 30px 1fr; gap: 8px; padding: 11px 8px; color: var(--ink); text-align: left; border: 0; border-left: 2px solid transparent; background: transparent; }.lesson-list button span { color: var(--coral); font-size: 11px; font-weight: 800; }.lesson-list button b { font-size: 13px; line-height: 1.45; }.lesson-list button:hover, .lesson-list button.active { border-left-color: var(--coral); background: var(--card-hi); }.lesson-panel { min-width: 0; }.lesson-progress { display: grid; grid-template-columns: 92px 1fr; align-items: center; gap: 14px; margin-bottom: 20px; color: var(--muted); font-size: 12px; }.progress-track { height: 3px; overflow: hidden; background: rgba(7,61,58,.14); }.progress-track i { display: block; width: 12.5%; height: 100%; background: var(--coral); transition: width .35s ease; }.lesson-grid { display: grid; gap: 30px; }.lesson-video-wrap { aspect-ratio: 16 / 9; overflow: hidden; background: var(--paper); }.lesson-video-wrap video { width: 100%; height: 100%; }.lesson-copy { max-width: 840px; }.lesson-copy h2 { margin-bottom: 14px; font-size: clamp(25px, 3.1vw, 39px); line-height: 1.2; }.lesson-summary { color: var(--muted); font-size: 16px; line-height: 1.8; }.lesson-sections { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 18px; margin: 25px 0; }.lesson-sections div { padding-top: 14px; border-top: 1px solid var(--line); }.lesson-sections h3 { margin-bottom: 7px; font-size: 16px; }.lesson-sections p { margin-bottom: 0; color: var(--muted); font-size: 14px; line-height: 1.75; }.lesson-resource-box { margin: 0 0 18px; padding: 16px 18px; border: 1px solid var(--line); background: var(--card-hi); }.lesson-resource-box span { display: block; margin-bottom: 10px; color: var(--coral); font-size: 11px; font-weight: 800; letter-spacing: .1em; }.lesson-resources { display: flex; flex-wrap: wrap; gap: 8px; }.practice-box { padding: 18px 20px; border-left: 3px solid var(--coral); background: var(--foam); }.practice-box span { color: var(--coral); font-size: 11px; font-weight: 800; letter-spacing: .1em; }.practice-box p { margin: 7px 0 0; line-height: 1.7; }.lesson-actions { display: flex; justify-content: space-between; margin-top: 24px; }.lesson-actions button { min-height: 40px; padding: 0 16px; color: var(--ink); border: 1px solid var(--line); border-radius: 3px; background: transparent; }.lesson-actions button.next { color: var(--on-accent); border-color: transparent; background: var(--accent); }.lesson-actions button:disabled { cursor: not-allowed; opacity: .38; }
.closing { padding: 120px 0 130px; }.closing > p:last-child { max-width: 650px; }.closing h2 { font-size: clamp(36px, 5vw, 62px); }
footer { display: flex; justify-content: space-between; padding: 24px clamp(24px, 5vw, 76px); color: var(--ink-2); font-size: 12px; background: var(--ink-deep); }
.reveal { opacity: 1; transform: none; }.reveal.is-pending { opacity: 0; transform: translateY(22px); transition: opacity .65s ease, transform .65s ease; }.reveal.visible { opacity: 1; transform: none; }

/* --- 2026-08-03 深化改造新增样式 --- */
.scene-fallback { display: grid; min-height: 220px; place-items: center; margin: 0; padding: 22px; color: var(--ink-2); text-align: center; line-height: 1.7; background: var(--line-hi); }

/* 方法匹配器二维决策图 */
.matcher-map-2d { min-height: 220px; padding: 10px; border: 1px solid var(--card-hi); background: var(--line-hi); }
.matcher-map-svg { width: 100%; height: 220px; }
.matcher-dot { fill: var(--ink-2); stroke: var(--ink-2); stroke-width: .4; transition: fill .2s, r .2s; }
.matcher-dot.active { fill: var(--mint-bright); stroke: var(--line-hi); r: 4; }
.matcher-dot-label { fill: var(--ink-2); font-size: 2.6px; text-anchor: middle; }
.matcher-axis-label { fill: var(--muted); font-size: 2.8px; }

/* PCA 二维/三维切换 */
.pca-canvas-2d { position: absolute; inset: 0; width: 100%; height: 100%; cursor: grab; touch-action: none; }
.pca-canvas-2d:active { cursor: grabbing; }
.pca-scene-3d { position: absolute; inset: 0; display: none; }
.pca-scene-3d.active { display: block; animation: space-dive .72s cubic-bezier(.18,.82,.28,1) forwards; }
.pca-scene-wrap.pca-2d-hidden .pca-canvas-2d { display: none; }

/* LAB 05/06/07 通用：滑杆控制、二维/三维画布切换、数值读数 */
.lab-controls { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 12px 24px; margin: 6px 0; }
.lab-controls label { display: grid; grid-template-columns: 1fr auto; align-items: center; gap: 8px; color: var(--ink-2); font-size: 13px; }
.lab-controls label input[type="range"] { grid-column: 1 / -1; accent-color: var(--mint-bright); }
.lab-controls output { display: inline-grid; min-width: 34px; place-items: center; padding: 0 4px; color: var(--ink-deep); font-weight: 800; font-size: 12px; background: var(--sun); }
.lab-canvas-wrap { position: relative; min-height: 260px; overflow: hidden; background: radial-gradient(circle at 50% 46%, color-mix(in srgb, var(--accent) 19%, transparent), transparent 30%), linear-gradient(138deg, rgba(0,0,0,.22), transparent 68%); }
.lab-canvas-2d { position: absolute; inset: 0; width: 100%; height: 100%; }
.lab-scene-3d { position: absolute; inset: 0; display: none; }
.lab-scene-3d.active { display: block; animation: space-dive .72s cubic-bezier(.18,.82,.28,1) forwards; }
.lab-scene-3d canvas { position: absolute; inset: 0; width: 100%; height: 100%; cursor: grab; touch-action: none; }
.lab-scene-3d canvas:active { cursor: grabbing; }
.lab-canvas-wrap.lab2d-hidden .lab-canvas-2d { display: none; }
.lab-readout { display: flex; flex-wrap: wrap; gap: 10px; margin-top: 12px; }
.lab-stat { display: grid; gap: 3px; padding: 8px 12px; min-width: 108px; border: 1px solid var(--card-hi); background: var(--line-hi); }
.lab-stat span { color: var(--muted); font-size: 10px; letter-spacing: .06em; }
.lab-stat b { color: var(--mint-bright); font-size: 15px; }
.lab-footer-controls { display: flex; flex-wrap: wrap; gap: 14px; margin-top: 10px; color: var(--muted); font-size: 12px; }

/* Williams 前样高亮 */
.grid-cell.pulse-prev { outline: 2px solid rgba(247,199,91,.55); }
.lesson-done-mark { justify-self: end; color: var(--mint-bright); font-weight: 800; }

/* 进阶专题手风琴 */
.topics-section { padding-block: 110px; background: var(--foam); }
.cn-standards-note { margin-top: 10px; padding: 10px 14px; border-left: 2px solid var(--line-hi); color: var(--muted); font-size: 13px; }
.cn-layer { margin-top: 54px; }
.cn-layer-heading { display: grid; grid-template-columns: 48px minmax(0, 1fr); gap: 18px; align-items: start; margin-bottom: 22px; }
.cn-layer-heading h3 { margin: 0 0 7px; font-size: 23px; }
.cn-layer-heading p { max-width: 760px; margin: 0; color: var(--muted); line-height: 1.7; }
.cn-layer-index { display: grid; place-items: center; width: 44px; height: 44px; border: 1px solid var(--line-hi); color: var(--ink-deep); font-weight: 800; background: var(--mint); }
.cn-document-list { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); border-top: 1px solid var(--line); border-left: 1px solid var(--line); }
.cn-document { min-width: 0; padding: 20px; border-right: 1px solid var(--line); border-bottom: 1px solid var(--line); background: var(--foam); }
.cn-document-meta { display: flex; flex-wrap: wrap; gap: 6px 12px; margin-bottom: 10px; color: var(--muted); font-size: 12px; }
.cn-document-industry { color: var(--ink-deep); font-weight: 800; }
.cn-document h4 { margin: 0; font-size: 16px; line-height: 1.5; }
.cn-document-status { min-height: 44px; margin: 10px 0 14px; color: var(--muted); font-size: 13px; line-height: 1.65; }
.cn-document-link { color: var(--ink-deep); font-size: 13px; font-weight: 800; text-underline-offset: 4px; }
.cn-profile-list { display: grid; gap: 12px; }
.cn-profile { border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); }
.cn-profile-header { display: grid; grid-template-columns: minmax(120px, auto) minmax(0, 1fr) auto; gap: 18px; align-items: center; width: 100%; padding: 18px 2px; border: 0; text-align: left; background: transparent; }
.cn-profile-header b { font-size: 17px; }
.cn-profile-code { color: var(--coral); font-size: 12px; font-weight: 800; }
.cn-profile.open .topic-chevron { transform: rotate(45deg); }
.cn-profile-body { max-width: 900px; padding: 0 0 22px 138px; }
.cn-profile-body h4 { margin: 18px 0 8px; font-size: 15px; }
.cn-profile-body p, .cn-profile-body li { color: var(--muted); line-height: 1.75; }
.cn-profile-summary { color: var(--ink); }
.cn-profile-output { padding-left: 13px; border-left: 3px solid var(--mint-bright); }
.topics-list { display: grid; gap: 14px; margin-top: 36px; }
.topic-card { border: 1px solid var(--line); background: var(--foam); }
.topic-header { display: flex; align-items: center; gap: 16px; width: 100%; padding: 20px 24px; text-align: left; border: 0; background: transparent; }
.topic-code { padding: 4px 8px; color: var(--ink-deep); font-size: 11px; font-weight: 800; letter-spacing: .1em; background: var(--mint); }
.topic-header b { flex: 1; font-size: 18px; }
.topic-chevron { color: var(--coral); font-size: 18px; font-weight: 800; }
.topic-card.open .topic-chevron { transform: rotate(45deg); }
.topic-body { padding: 0 24px 26px; }
.topic-body h4 { margin: 18px 0 8px; font-size: 15px; }
.topic-body p, .topic-body li { color: var(--muted); line-height: 1.75; }
.topic-summary { color: var(--ink); font-size: 15px; }
.topic-body .wrong { padding-left: 13px; border-left: 3px solid var(--coral); }

@media (max-width: 720px) {
  .cn-document-list { grid-template-columns: 1fr; }
  .cn-layer-heading { grid-template-columns: 40px minmax(0, 1fr); gap: 12px; }
  .cn-layer-index { width: 38px; height: 38px; }
  .cn-layer-heading h3 { font-size: 20px; }
  .cn-profile-header { grid-template-columns: 1fr auto; gap: 8px 14px; }
  .cn-profile-code { grid-column: 1 / -1; }
  .cn-profile-body { padding-left: 0; }
}
.topic-body .fix { padding-left: 13px; color: var(--ink); border-left: 3px solid var(--mint-bright); }
.topic-body .worked-numbers { padding: 10px 12px; color: var(--ink); background: var(--foam); }
.cross-links { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 14px; }
.cross-link { display: inline-flex; align-items: center; min-height: 32px; padding: 0 12px; color: var(--ink); font-size: 12px; font-weight: 700; text-decoration: none; border: 1px solid var(--line); border-radius: 3px; }
.cross-link:hover { border-color: var(--ink); }

/* 课程页新增结构块 */
.lesson-meta-box { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 18px; margin: 18px 0; padding: 16px 18px; border: 1px solid var(--line); background: var(--card-hi); }
.lesson-meta-box span { display: block; margin-bottom: 8px; color: var(--coral); font-size: 11px; font-weight: 800; letter-spacing: .1em; }
.lesson-meta-box ul { margin: 0; padding-left: 18px; color: var(--muted); font-size: 13px; line-height: 1.7; }
.lesson-block { margin: 20px 0; padding: 16px 18px; border: 1px solid var(--line); background: var(--foam); }
.lesson-block h3 { margin-bottom: 8px; font-size: 15px; }
.lesson-block p { margin: 0 0 8px; color: var(--muted); font-size: 14px; line-height: 1.75; }
.lesson-block ol { margin: 0 0 8px; padding-left: 18px; color: var(--muted); font-size: 14px; line-height: 1.75; }
.lesson-block ul { margin: 0; padding-left: 18px; color: var(--muted); font-size: 13px; line-height: 1.7; }
.worked-example-box .worked-numbers { padding: 8px 10px; color: var(--ink); background: var(--foam); }
.worked-example-box .worked-conclusion { color: var(--ink); font-weight: 600; }
.misconception-box .wrong { padding-left: 13px; border-left: 3px solid var(--coral); }
.misconception-box .fix { padding-left: 13px; color: var(--ink); border-left: 3px solid var(--mint-bright); }
.boundaries-box { background: var(--foam); }
.references-box small, .references-box li { font-size: 12px; }

/* 本地进度面板 */
.progress-panel { display: flex; flex-wrap: wrap; align-items: center; gap: 16px; margin-top: 34px; padding: 18px 22px; border-top: 1px solid var(--line); }
.progress-summary { margin: 0; font-weight: 700; }
.progress-notice { margin: 0; color: var(--muted); font-size: 12px; }

/* 数据计算沙盒（2026-08-03 新增：CSV 上传/粘贴，浏览器本地实时 PCA） */
.sandbox-section { padding-block: 100px; background: var(--paper); }
.sandbox-section code { padding: 1px 5px; font-size: 13px; background: var(--foam); border-radius: 3px; }
.sandbox-grid { display: grid; grid-template-columns: minmax(280px, .85fr) minmax(320px, 1.15fr); gap: 28px; margin-top: 32px; }
.sandbox-input-col { display: grid; align-content: start; gap: 10px; }
.sandbox-label { color: var(--ink); font-size: 13px; font-weight: 700; }
.sandbox-input-col input[type="file"] { padding: 8px; border: 1px solid var(--line); border-radius: 3px; background: var(--foam); }
.sandbox-textarea { padding: 10px 12px; color: var(--ink); font: 13px/1.6 "SFMono-Regular", Menlo, Consolas, monospace; border: 1px solid var(--line); border-radius: 3px; background: var(--foam); resize: vertical; }
.sandbox-actions { display: flex; flex-wrap: wrap; align-items: center; gap: 14px; margin-top: 4px; }
.sandbox-primary-button { min-height: 40px; padding: 0 20px; color: var(--ink-deep); font-weight: 800; border: 0; border-radius: 3px; background: var(--mint-bright); }
.sandbox-primary-button:hover { background: var(--mint); }
.sandbox-text-button { padding: 0; color: var(--ink); font-size: 13px; font-weight: 700; text-decoration: none; border: 0; border-bottom: 1px solid currentColor; background: transparent; }
.sandbox-status { margin: 4px 0 0; min-height: 20px; color: var(--muted); font-size: 12px; line-height: 1.6; }
.sandbox-status.sandbox-status-error { color: var(--coral); font-weight: 700; }
.sandbox-output-col { display: grid; grid-template-rows: auto 1fr; gap: 16px; }
.sandbox-canvas { display: block; width: 100%; height: 260px; background: radial-gradient(circle at 50% 46%, color-mix(in srgb, var(--accent) 12%, transparent), transparent 30%), var(--ink-deep); border-radius: 4px; }
.sandbox-results { display: grid; gap: 10px; }
.sandbox-variance-line, .sandbox-loadings-title { margin: 0; color: var(--muted); font-size: 13px; line-height: 1.6; }
.sandbox-table { width: 100%; border-collapse: collapse; font-size: 12px; }
.sandbox-table th, .sandbox-table td { padding: 6px 8px; text-align: left; border-bottom: 1px solid var(--line); }
.sandbox-table th { color: var(--muted); font-weight: 700; }
.sandbox-table td { color: var(--ink); }
.sandbox-disclaimer { margin-top: 18px; color: var(--muted); font-size: 12px; line-height: 1.7; }
@media (max-width: 880px) { .sandbox-grid { grid-template-columns: 1fr; } }

@keyframes spin { to { transform: rotate(360deg); } } @keyframes breathe { 50% { transform: scale(1.08); opacity: .55; } } @keyframes drift-grid { to { background-position: 48px 48px; } } @keyframes space-dive { 0% { opacity: 0; transform: perspective(1000px) translateY(-16px) scale(.96); } 65% { opacity: 1; transform: perspective(1000px) translateY(3px) scale(1.01); } 100% { opacity: 1; transform: perspective(1000px) translateY(0) scale(1); } }
/* 880 以下整条 nav 隐藏——但「平台首页」现在住在 nav 里面，它是这一页回到
   门户的唯一路径，不能跟着消失。所以隐藏的是 nav 里的锚点，不是 nav 本身。 */
@media (max-width: 880px) { nav > a[href^="#"] { display: none; } nav { gap: 0; } .platform-home { border-left: 0; padding-left: 0; margin-left: 0; }.hero { grid-template-columns: 1fr; min-height: 690px; }.hero-orbit { width: min(74vw, 370px); margin: 25px auto -50px; }.hero-copy-wrap { z-index: 1; }.path-steps { grid-template-columns: repeat(2, 1fr); }.lexicon-layout { grid-template-columns: 1fr; }.lexicon-preview { width: 100%; }.lab { grid-template-columns: 1fr; gap: 20px; }.matcher-options, .matcher-map-2d, .matcher-result, .method-space, .mode-switch, .cup-row, .lab-feedback, .lab-footer, .control-line, .lab-footer-controls, .sequence-key, .williams-grid, .order-space, .lab-note, .pca-layout, .lab-controls, .lab-canvas-wrap, .lab-readout { grid-column: 1; }.toolkit-panel, .quiz-layout, .course-layout { grid-template-columns: 1fr; gap: 42px; }.quiz-certificate-content { grid-template-columns: 1fr; }.course-nav { position: static; }.lesson-list { grid-template-columns: repeat(2, minmax(0, 1fr)); }.pca-layout { grid-template-columns: 1fr; }.system-map { grid-template-columns: repeat(2, 1fr); }.system-map div:nth-child(2) { border-right: 0; }.system-map div:nth-child(-n + 2) { border-bottom: 1px solid var(--line); } }
@media (max-width: 620px) { .site-header { min-height: 62px; padding-inline: 18px; }.brand img { width: 190px; height: 40px; }.platform-home { width: 38px; padding-left: 12px; }.platform-home b { display: none; }.section-wrap { width: min(100% - 32px, 1180px); }.hero { min-height: 720px; padding-inline: 20px; }.mobile-title-break { display: inline; }.hero-copy { font-size: 15px; }.hero-metrics { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 16px; margin-top: 35px; }.hero-orbit { width: 295px; margin-bottom: -12px; }.path-section, .lexicon-section, .toolkit-section, .quiz-section, .system-section, .course-section { padding-block: 80px; }.path-steps { grid-template-columns: 1fr; gap: 22px; border: 0; }.path-steps li, .path-steps li:not(:first-child) { padding: 0 0 20px; border: 0; border-bottom: 1px solid var(--line); }.lexicon-metrics { grid-template-columns: repeat(2, minmax(0, 1fr)); }.lexicon-preview { aspect-ratio: 4 / 3; }.labs-section { padding-block: 75px; }.lab { margin-top: 24px; padding: 24px 17px; }.lab-intro h3 { font-size: 23px; }.matcher-options, .lesson-sections { grid-template-columns: 1fr; }.matcher-result { grid-template-columns: 1fr; gap: 8px; }.cup-row { gap: 12px; }.cup { width: 82px; height: 96px; font-size: 14px; }.lab-footer { align-items: flex-start; flex-direction: column; }.control-line { grid-template-columns: 1fr 38px; }.control-line label { grid-column: 1 / -1; }.williams-grid { grid-template-columns: 69px repeat(var(--sample-count, 4), minmax(28px, 1fr)); }.grid-head, .grid-label, .grid-cell { min-height: 31px; font-size: 10px; }.pca-scene-wrap { min-height: 330px; }.pca-view-controls { right: 10px; bottom: 10px; max-width: 230px; }.pca-view-button { padding-inline: 8px; font-size: 10px; }.toolkit-tabs { display: grid; grid-template-columns: 1fr; width: 100%; }.toolkit-card { min-height: auto; padding: 20px; }.quiz-card { min-height: auto; padding: 22px; }.quiz-card h3 { min-height: auto; }.quiz-certificate-guide summary { align-items: flex-start; flex-direction: column; gap: 3px; padding-right: 48px; position: relative; }.quiz-certificate-guide summary::after { position: absolute; right: 17px; top: 16px; }.quiz-certificate-content { gap: 22px; padding: 18px; }.system-map { grid-template-columns: 1fr; }.system-map div, .system-map div:nth-child(2) { border-right: 0; border-bottom: 1px solid var(--line); }.system-map div:last-child { border-bottom: 0; }.course-nav h2 { font-size: 35px; }.lesson-list { grid-template-columns: 1fr; }.lesson-actions { gap: 12px; }.lesson-actions button { flex: 1; padding-inline: 10px; }.lesson-meta-box { grid-template-columns: 1fr; }.lab-controls { grid-template-columns: 1fr; }.lab-canvas-wrap { min-height: 220px; }.matcher-map-svg { height: 180px; }.topic-header { padding: 16px 18px; gap: 10px; }.topic-header b { font-size: 15px; }.topic-body { padding: 0 18px 20px; } footer { gap: 10px; padding-inline: 18px; } }
.quiz-level { display: inline-flex; margin: 0 0 10px; padding: 5px 9px; border: 1px solid var(--quiz-level-accent); color: var(--quiz-level-accent); font-size: 12px; font-weight: 800; }

:root[data-theme="light"] .quiz-section[data-quiz-level="start"] {
  --quiz-copy: #12332d; --quiz-copy-muted: #365f56; --quiz-level-accent: #0f766e;
  background: linear-gradient(132deg, #f1fbf6 0%, #caeadc 58%, #e2f2ed 100%);
}
:root[data-theme="light"] .quiz-section[data-quiz-level="build"] {
  --quiz-copy: #251943; --quiz-copy-muted: #5b4b78; --quiz-level-accent: #6d28d9;
  background: linear-gradient(132deg, #f6f2ff 0%, #ddd1fa 58%, #ebe6f5 100%);
}
:root[data-theme="light"] .quiz-section[data-quiz-level="advanced"] {
  --quiz-copy: #f7f3ff; --quiz-copy-muted: #d8cce8; --quiz-level-accent: #ffaaa2;
  background: linear-gradient(132deg, #241b36 0%, #432b60 58%, #172235 100%);
}
@media (prefers-color-scheme: light) {
  :root:not([data-theme="dark"]) .quiz-section[data-quiz-level="start"] {
    --quiz-copy: #12332d; --quiz-copy-muted: #365f56; --quiz-level-accent: #0f766e;
    background: linear-gradient(132deg, #f1fbf6 0%, #caeadc 58%, #e2f2ed 100%);
  }
  :root:not([data-theme="dark"]) .quiz-section[data-quiz-level="build"] {
    --quiz-copy: #251943; --quiz-copy-muted: #5b4b78; --quiz-level-accent: #6d28d9;
    background: linear-gradient(132deg, #f6f2ff 0%, #ddd1fa 58%, #ebe6f5 100%);
  }
  :root:not([data-theme="dark"]) .quiz-section[data-quiz-level="advanced"] {
    --quiz-copy: #f7f3ff; --quiz-copy-muted: #d8cce8; --quiz-level-accent: #ffaaa2;
    background: linear-gradient(132deg, #241b36 0%, #432b60 58%, #172235 100%);
  }
}
@media (max-width: 620px) { .case-level-heading { align-items: flex-start; flex-direction: column; gap: 6px; }.case-level-heading p { text-align: left; } }
@media (prefers-reduced-motion: reduce) { html { scroll-behavior: auto; }.hero-grid, .hero-signal, .orbit-ring { animation: none; }.reveal, .reveal.is-pending { opacity: 1; transform: none; transition: none; } *, *::before, *::after { transition-duration: .01ms !important; animation-duration: .01ms !important; animation-iteration-count: 1 !important; } }

/* ── 主持讲解词折叠面板（2026-08-06 新增，内容对应讲解词文档 2026-08-05 版） ── */
.lab-notes { margin-top: 26px; border: 1px solid rgba(247, 199, 91, .38); border-radius: 10px; background: rgba(3, 47, 45, .55); }
.lab > .lab-notes { grid-column: 2; margin-top: 20px; }
.lab-notes summary { display: flex; flex-wrap: wrap; align-items: center; gap: 10px 12px; padding: 12px 16px; cursor: pointer; list-style: none; border-radius: 10px; }
.lab-notes summary::-webkit-details-marker { display: none; }
.lab-notes summary:focus-visible { outline: 3px solid var(--sun); outline-offset: 2px; }
.lab-notes summary::after { content: ""; margin-left: auto; width: 9px; height: 9px; border-right: 2px solid var(--sun); border-bottom: 2px solid var(--sun); transform: rotate(45deg); transition: transform .2s ease; }
.lab-notes[open] summary::after { transform: rotate(225deg); }
.lab-notes-kicker { flex: none; padding: 3px 10px; border-radius: 999px; background: var(--sun); color: var(--paper); font-size: 11px; font-weight: 800; letter-spacing: .08em; }
.lab-notes-summary-text { color: var(--ink-2); font-size: 13.5px; font-weight: 600; }
.lab-notes-body { padding: 2px 18px 20px; border-top: 1px dashed var(--ink-2); color: var(--ink-2); font-size: 13.5px; line-height: 1.8; }
.lab-notes-body h4 { margin: 18px 0 8px; color: var(--mint-bright); font-size: 13px; letter-spacing: .06em; }
.lab-notes-course { margin: 12px 0 0; color: var(--ink-2); font-size: 12.5px; }
.lab-notes-lead { margin: 12px 0 0; color: var(--ink-2); }
.lab-notes-body blockquote { margin: 0; padding: 10px 14px; border-left: 3px solid var(--mint-bright); background: rgba(125, 227, 189, .08); color: var(--mint); }
.lab-notes-body ol { margin: 0; padding-left: 20px; }
.lab-notes-body li { margin: 4px 0; }
.lab-notes-table { width: 100%; margin: 12px 0 0; border-collapse: collapse; font-size: 12.5px; }
.lab-notes-table th, .lab-notes-table td { padding: 7px 10px; border-bottom: 1px solid var(--ink-2); text-align: left; vertical-align: top; }
.lab-notes-table th { color: var(--mint-bright); font-size: 12px; letter-spacing: .05em; }
.lab-notes-table td:first-child { white-space: nowrap; color: var(--sun); font-weight: 700; }
.lab-notes-numbers { display: grid; grid-template-columns: minmax(150px, 250px) minmax(0, 1fr); gap: 6px 16px; margin: 0; }
.lab-notes-numbers dt { color: var(--ink-2); }
.lab-notes-numbers dd { margin: 0; color: var(--mint); }
.lab-notes-numbers dt.is-default { color: var(--ink); font-weight: 800; }
.lab-notes-numbers dd.is-default { color: var(--sun); font-weight: 800; }
.lab-notes-note { margin: 8px 0 0; color: var(--ink-2); font-size: 12.5px; }
.lab-notes-pitfall { margin: 10px 0; padding: 10px 14px; border: 1px solid rgba(244, 111, 94, .3); border-radius: 8px; background: rgba(244, 111, 94, .09); }
.lab-notes-pitfall p { margin: 4px 0; }
.lab-notes-pitfall .dont { color: var(--ink-2); }
.lab-notes-pitfall .dont b { color: var(--coral); }
.lab-notes-pitfall .say b { color: var(--mint-bright); }
.lab-notes-body .qa-q { margin: 10px 0 2px; color: var(--ink); }
.lab-notes-body .qa-q b { color: var(--sun); }
.lab-notes-body .qa-a { margin: 0; }
.lab-notes-body .qa-a b { color: var(--mint-bright); }
.lab-notes-closing { margin: 16px 0 0; padding: 10px 14px; border-left: 3px solid var(--sun); background: rgba(247, 199, 91, .1); color: var(--mint); font-weight: 700; }
.lab-notes-closing b { color: var(--sun); }
@media (max-width: 880px) { .lab > .lab-notes { grid-column: 1; } .lab-notes-numbers { grid-template-columns: 1fr; gap: 2px 0; } .lab-notes-numbers dt { margin-top: 8px; } }

/* ── 入门 10 问 ────────────────────────────────────────────────────
   放在学习路径之前：路径是从「分析型 vs 享乐型」切入的，对第一次接触感官
   评价的人门槛偏高。沿用本页已有的令牌，不另起一套配色。 */
.basics-section { padding-block: clamp(70px, 8vw, 110px); }
.basics-list { margin: 0; padding: 0; list-style: none; display: grid; grid-template-columns: repeat(auto-fit, minmax(300px, 1fr)); gap: clamp(16px, 2vw, 26px); }
.basic { position: relative; padding: 26px 24px 24px; border: 1px solid var(--line); border-radius: 16px; background: var(--paper); }
.basic-no { display: block; margin-bottom: 12px; color: var(--coral); font-size: 12px; font-weight: 800; letter-spacing: .16em; }
.basic h3 { margin: 0 0 10px; font-size: 18px; line-height: 1.35; }
.basic p { margin: 0; color: var(--ink-2); font-size: 14.6px; line-height: 1.75; }
.basics-next { margin: clamp(26px, 3vw, 38px) 0 0; font-size: 15px; color: var(--ink-2); }
.basics-next a { margin-left: 8px; color: var(--accent); font-weight: 700; text-decoration: none; border-bottom: 1px solid transparent; }
.basics-next a:hover { border-bottom-color: var(--accent); }
@media (max-width: 620px) { .basics-section { padding-block: 70px; } .basic { padding: 22px 18px; } }


/* ══════════════════════════════════════════════════════════════════
   与门户统一的表层：页眉、hero、区块标题、卡片、按钮
   结构不动，只重做视觉语言。
   ══════════════════════════════════════════════════════════════════ */

.site-header {
  background: color-mix(in srgb, var(--paper) 82%, transparent);
  backdrop-filter: blur(14px) saturate(140%);
  border-bottom: 1px solid var(--line);
}
.brand img { height: 46px; width: auto; }

nav a {
  position: relative;
  color: var(--ink-2); font-size: 14px; font-weight: 700;
  padding: 6px 2px;
  transition: color .25s var(--ease);
}
nav a::after {
  content: ""; position: absolute; left: 0; bottom: 0;
  width: 100%; height: 1.5px; background: var(--accent);
  transform: scaleX(0); transform-origin: right;
  transition: transform .35s var(--ease);
}
nav a:hover { color: var(--ink); }
nav a:hover::after { transform: scaleX(1); transform-origin: left; }

/* 首屏：换成门户那套极光 + 网格纱，去掉原来的绿色径向渐变 */
.hero {
  background: var(--paper);
  color: var(--ink);
  isolation: isolate;
}
.hero::before {
  content: ""; position: absolute; inset: -20% -10%; z-index: -2;
  filter: blur(72px); opacity: var(--aurora-a);
  background:
    radial-gradient(38vw 38vw at 72% 12%, color-mix(in srgb, var(--accent) 55%, transparent), transparent 68%),
    radial-gradient(32vw 32vw at 22% 82%, color-mix(in srgb, var(--teal) 30%, transparent), transparent 70%);
}
.hero-grid {
  background-image:
    linear-gradient(var(--veil) 1px, transparent 1px),
    linear-gradient(90deg, var(--veil) 1px, transparent 1px);
  opacity: 1;
}
.hero-signal { border-color: var(--line-hi); }

h1 { font-weight: 800; letter-spacing: -.02em; }
h1 em { color: var(--accent-soft); font-style: normal; }

.eyebrow { font-size: 12px; font-weight: 800; letter-spacing: .24em; color: var(--accent); }
.eyebrow.ink, .eyebrow.mint { color: var(--accent); }

.section-heading h2 {
  font-size: clamp(28px, 4vw, 50px); font-weight: 800; letter-spacing: -.015em;
}
.section-heading p { color: var(--ink-2); }

/* 卡片统一成门户那一套：极淡面 + 细描边 + 悬停微抬 */
.path-steps li, .lab, .topic, .toolkit-card, .quiz-card, .lesson-item,
.basic, .lexicon-preview, .sandbox-panel {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--r);
  transition: transform .4s var(--ease), background .4s var(--ease), border-color .4s var(--ease);
}
.lab:hover, .topic:hover, .toolkit-card:hover, .quiz-card:hover, .basic:hover {
  transform: translateY(-4px);
  background: var(--card-hi);
  border-color: var(--line-hi);
}

.button, .button-primary, .lab-footer button, .mode-button, .toolkit-tab {
  border-radius: 999px;
  font-weight: 700;
  transition: transform .3s var(--ease), background .3s var(--ease),
              border-color .3s var(--ease), box-shadow .3s var(--ease);
}
.button-primary {
  color: var(--on-accent);
  background: linear-gradient(120deg, var(--accent), #6742e0);
  border: 1px solid transparent;
  box-shadow: 0 12px 34px -14px color-mix(in srgb, var(--accent) 85%, transparent);
}
.button-primary:hover { transform: translateY(-2px); }

/* 对错反馈是固定语义色，不跟主题走；浅色下要压深才看得清 */
:root[data-theme="light"] .lab-feedback.correct { color: #3f6212; }
:root[data-theme="light"] .lab-feedback.incorrect { color: #b91c1c; }
@media (prefers-color-scheme: light) {
  :root:not([data-theme="dark"]) .lab-feedback.correct { color: #3f6212; }
  :root:not([data-theme="dark"]) .lab-feedback.incorrect { color: #b91c1c; }
}

/* 明暗切换按钮：与门户同一个形状 */
.theme-toggle {
  display: inline-grid; place-items: center;
  width: 38px; height: 38px; padding: 0;
  border-radius: 50%;
  color: var(--ink-2);
  background: var(--card);
  border: 1px solid var(--line);
  transition: color .25s var(--ease), background .25s var(--ease),
              border-color .25s var(--ease), transform .25s var(--ease);
}
.theme-toggle:hover { color: var(--ink); background: var(--card-hi); transform: rotate(12deg); }
.theme-toggle svg {
  grid-area: 1 / 1; width: 18px; height: 18px;
  fill: none; stroke: currentColor; stroke-width: 1.9;
  stroke-linecap: round; stroke-linejoin: round;
  transition: opacity .25s var(--ease), transform .35s var(--ease);
}
.i-moon { opacity: 0; transform: scale(.6) rotate(-40deg); }
:root[data-theme="light"] .i-sun { opacity: 0; transform: scale(.6) rotate(40deg); }
:root[data-theme="light"] .i-moon { opacity: 1; transform: none; }
@media (prefers-color-scheme: light) {
  :root:not([data-theme="dark"]) .i-sun { opacity: 0; transform: scale(.6) rotate(40deg); }
  :root:not([data-theme="dark"]) .i-moon { opacity: 1; transform: none; }
}

footer { border-top: 1px solid var(--line); color: var(--muted); }


/* 固定浅底的元素才需要固定深字：.sample-* 是样品区分色（浅绿/杏/黄/淡紫），
   不随主题变，所以压在上面的文字必须固定为深色。
   .cup 本身用的是 var(--card) 深色面，不属于这一类——先前把它一并设成深字，
   结果是深字压深底，反而看不见。 */
[class*="sample-"], .grid-cell[class*="sample-"] { color: #0d1b2a; }


/* 实验里的控件（模式切换、PCA 视图、图例胶囊、图标按钮）原来各自写死颜色，
   主题一换就出现浅字压浅底。统一挂到令牌上，选中态用强调色实底 + 反色。 */
.mode-button, .pca-view-button, .pca-pill, .icon-button, .lab-footer button {
  color: var(--ink-2);
  background: var(--card);
  border: 1px solid var(--line);
}
.mode-button:hover, .pca-view-button:hover, .icon-button:hover, .lab-footer button:hover {
  color: var(--ink); background: var(--card-hi); border-color: var(--line-hi);
}
.mode-button.active, .pca-view-button.active, .pca-view-button[aria-pressed="true"] {
  color: var(--on-accent); background: var(--accent); border-color: transparent;
}


/* 实底小标签：底是强调色/珊瑚色，文字必须是反色。
   原设计里这里写的是 --ink-deep（深绿），在深色主题下 --ink-deep 已是浅色，
   浅字压彩底就糊了。 */
.toolkit-label, .topic-code {
  color: var(--on-accent);
  background: var(--accent);
}
.copy-button { color: #fff; background: var(--coral); }
.copy-button:hover { filter: brightness(1.08); }

/* eyebrow 在彩色/深色区块内出现时，用正文色而不是强调色，保证读得清 */
.labs-section .eyebrow, .course-section .eyebrow { color: var(--accent-soft); }


/* 标签有两种变体，底色不同，文字必须各配各的——先前用一刀切的规则，
   修好一种就翻掉另一种，来回都不对：
   .standard-method  底是 var(--accent)（随主题的深紫）→ 反色白字
   .standard-product 底是 #ffe8c9（固定杏色，不随主题）→ 固定深字 */
.standard-method .toolkit-label { color: var(--on-accent); }
.standard-product .toolkit-label { color: #4a2c06; }

/* 珊瑚底上白字只有 2.9:1；深字在两个主题下都够 */
.copy-button { color: #2a0b08; background: var(--coral); }


/* ══ 分组下拉导航 ══════════════════════════════════════════════ */
.nav-group { position: relative; }
.nav-trigger, .nav-link {
  display: inline-flex; align-items: center; gap: 5px;
  padding: 8px 4px;
  color: var(--ink-2); font-size: 14px; font-weight: 700;
  background: none; border: 0; cursor: pointer;
  transition: color .25s var(--ease);
}
.nav-trigger svg {
  width: 15px; height: 15px; fill: none; stroke: currentColor;
  stroke-width: 2.2; stroke-linecap: round; stroke-linejoin: round;
  transition: transform .28s var(--ease);
}
.nav-group.open .nav-trigger svg { transform: rotate(180deg); }
.nav-trigger:hover, .nav-link:hover, .nav-group.open .nav-trigger { color: var(--ink); }

.nav-menu {
  position: absolute; top: calc(100% + 10px); left: 50%;
  transform: translateX(-50%) translateY(-6px);
  min-width: 168px; padding: 8px;
  display: grid; gap: 2px;
  background: var(--foam);
  border: 1px solid var(--line);
  border-radius: 14px;
  box-shadow: var(--shadow);
  opacity: 0; visibility: hidden; pointer-events: none;
  transition: opacity .22s var(--ease), transform .22s var(--ease), visibility .22s;
  z-index: 40;
}
/* 悬停展开时指针要能从触发器平移到菜单，中间不能断——留一条透明桥 */
.nav-group::after {
  content: ""; position: absolute; left: 0; right: 0; top: 100%; height: 12px;
}
.nav-group.open .nav-menu {
  opacity: 1; visibility: visible; pointer-events: auto;
  transform: translateX(-50%) translateY(0);
}
.nav-menu a {
  padding: 9px 12px; border-radius: 9px;
  color: var(--ink-2); font-size: 13.5px; font-weight: 600;
  white-space: nowrap;
  transition: color .2s var(--ease), background .2s var(--ease);
}
.nav-menu a:hover { color: var(--ink); background: var(--card-hi); }
.nav-menu a::after { display: none; }   /* 不要继承 nav a 的下划线动画 */

@media (max-width: 880px) {
  .header-tools { gap: 8px; }
  .academy-menu-toggle {
    display: inline-grid; place-items: center; flex: 0 0 auto;
    width: 38px; height: 38px; padding: 0;
    color: var(--ink-2); background: var(--card);
    border: 1px solid var(--line); border-radius: 50%;
  }
  .academy-menu-toggle:hover, .academy-menu-toggle[aria-expanded="true"] {
    color: var(--ink); background: var(--card-hi); border-color: var(--line-hi);
  }
  .academy-menu-toggle svg {
    width: 19px; height: 19px; fill: none; stroke: currentColor;
    stroke-width: 2; stroke-linecap: round;
  }
  #academyNav { position: static; gap: 0; }
  .academy-nav-panel {
    position: absolute; top: calc(100% + 8px); right: 12px; left: 12px;
    max-height: calc(100vh - 92px); padding: 10px; overflow-y: auto;
    display: none; gap: 4px;
    background: var(--foam); border: 1px solid var(--line);
    border-radius: 8px; box-shadow: var(--shadow);
  }
  #academyNav.mobile-open .academy-nav-panel { display: grid; }
  .academy-nav-panel .nav-group, .academy-nav-panel .nav-link { display: block; }
  .academy-nav-panel .nav-trigger, .academy-nav-panel > .nav-link {
    width: 100%; min-height: 44px; padding: 10px 12px;
    justify-content: space-between; border-radius: 5px;
  }
  .academy-nav-panel > .nav-link { display: flex; align-items: center; }
  .academy-nav-panel .nav-trigger:hover, .academy-nav-panel > .nav-link:hover,
  .academy-nav-panel .nav-trigger.active, .academy-nav-panel > .nav-link.active {
    background: var(--card-hi);
  }
  .academy-nav-panel .nav-trigger.active::after,
  .academy-nav-panel > .nav-link.active::after { display: none; }
  .academy-nav-panel .nav-group::after { display: none; }
  .academy-nav-panel .nav-menu {
    position: static; min-width: 0; padding: 0 8px 6px 22px;
    display: none; transform: none; opacity: 1; visibility: visible;
    pointer-events: auto; background: transparent; border: 0;
    border-radius: 0; box-shadow: none; transition: none;
  }
  .academy-nav-panel .nav-group.open .nav-menu { display: grid; transform: none; }
  .academy-nav-panel .nav-menu a { min-height: 40px; padding: 10px 12px; white-space: normal; }
}

@media (max-width: 620px) {
  .brand img { width: min(38vw, 146px); height: 38px; }
  .header-tools { gap: 6px; }
  .academy-menu-toggle, .theme-toggle { width: 36px; height: 36px; }
  .language-toggle { width: 38px; min-height: 36px; }
  .platform-home { width: 34px; padding-left: 8px; }
}


/* ══ 分组视图 ══════════════════════════════════════════════════
   一次只显示一组。hidden 属性在某些 UA 上会被 display:flex/grid 覆盖，
   所以这里显式压住——章节里有 grid 布局。 */
section[hidden] { display: none !important; }

.nav-trigger.active, .nav-link.active { color: var(--ink); }
.nav-trigger.active::after, .nav-link.active::after {
  content: ""; position: absolute; left: 4px; right: 4px; bottom: 0;
  height: 2px; border-radius: 2px; background: var(--accent);
}
.nav-trigger, .nav-link { position: relative; }
.nav-menu a.active { color: var(--ink); background: var(--card-hi); }