:root {
  --ink: #17211b;
  --ink-soft: #435047;
  --paper: #f7f7f2;
  --white: #ffffff;
  --line: #d9ddd8;
  --red: #d45542;
  --red-dark: #a83c2e;
  --green: #2f7160;
  --green-dark: #183f35;
  --gold: #e4ac48;
  --mist: #e9f0ec;
  --shadow: 0 24px 70px rgba(23, 33, 27, 0.12);
  --shell: min(1180px, calc(100% - 48px));
  --font-sans: "Microsoft YaHei", "PingFang SC", "Noto Sans CJK SC", system-ui, sans-serif;
  --font-serif: "STSong", "SimSun", "Noto Serif CJK SC", serif;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body { margin: 0; color: var(--ink); background: var(--paper); font-family: var(--font-sans); font-size: 16px; line-height: 1.7; letter-spacing: 0; }
body.menu-open { overflow: hidden; }
a { color: inherit; text-decoration: none; }
button, input, select, textarea { font: inherit; letter-spacing: 0; }
button { color: inherit; }
img, svg { display: block; max-width: 100%; }
h1, h2, h3, p { margin-top: 0; }
h1, h2, h3 { line-height: 1.15; letter-spacing: 0; }
h1, h2 { font-family: var(--font-serif); font-weight: 700; }
p { color: var(--ink-soft); }

.skip-link { position: fixed; z-index: 200; top: 12px; left: 12px; transform: translateY(-150%); background: var(--ink); color: white; padding: 10px 16px; border-radius: 4px; }
.skip-link:focus { transform: translateY(0); }
.section-shell { width: var(--shell); margin-inline: auto; }

.site-header { position: fixed; z-index: 100; top: 0; left: 0; width: 100%; transition: background 180ms ease, box-shadow 180ms ease; }
.site-header.is-scrolled, .site-header.header-solid { background: rgba(247, 247, 242, 0.96); box-shadow: 0 1px 0 rgba(23, 33, 27, 0.1); backdrop-filter: blur(14px); }
.nav-shell { width: var(--shell); min-height: 76px; margin: auto; display: flex; align-items: center; gap: 34px; }
.brand { display: inline-flex; align-items: center; gap: 10px; flex: none; }
.brand-mark { position: relative; width: 38px; height: 38px; display: inline-grid; place-items: center; overflow: hidden; border: 0; border-radius: 9px; background: linear-gradient(145deg, #43d9bd, #2fb78f 68%, #91df78); color: white; box-shadow: 0 5px 14px rgba(57,168,140,.18); font-family: var(--font-serif); font-size: 24px; font-weight: 700; line-height: 1; }
.brand-mark::after { content: ""; position: absolute; right: 3px; bottom: 4px; width: 10px; height: 5px; transform: rotate(-28deg); border-radius: 100% 0 100% 0; background: #d8f39a; }
.brand-name { font-family: var(--font-serif); font-size: 22px; font-weight: 700; }
.desktop-nav { display: flex; align-items: center; gap: 30px; margin-left: auto; }
.desktop-nav a { position: relative; color: #37423b; font-size: 14px; }
.desktop-nav a::after { content: ""; position: absolute; right: 0; bottom: -8px; left: 0; height: 2px; transform: scaleX(0); background: var(--red); transition: transform 160ms ease; }
.desktop-nav a:hover::after, .desktop-nav a.active::after { transform: scaleX(1); }
.nav-cta { display: inline-flex; align-items: center; gap: 10px; min-height: 42px; padding: 0 18px; border: 1px solid var(--ink); border-radius: 4px; font-size: 14px; font-weight: 700; transition: background 160ms ease, color 160ms ease; }
.nav-cta:hover { background: var(--ink); color: white; }
.menu-button { display: none; width: 42px; height: 42px; margin-left: auto; border: 0; background: transparent; padding: 9px; cursor: pointer; }
.menu-button span { display: block; width: 24px; height: 2px; margin: 5px auto; background: var(--ink); transition: transform 160ms ease, opacity 160ms ease; }
.menu-button[aria-expanded="true"] span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.menu-button[aria-expanded="true"] span:nth-child(2) { opacity: 0; }
.menu-button[aria-expanded="true"] span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }
.mobile-nav { display: none; }

.hero { position: relative; min-height: 880px; overflow: hidden; padding: 148px 0 0; background: var(--paper); border-bottom: 1px solid var(--line); }
.hero::before { content: ""; position: absolute; inset: 0; opacity: 0.35; background-image: linear-gradient(rgba(23,33,27,.055) 1px, transparent 1px), linear-gradient(90deg, rgba(23,33,27,.055) 1px, transparent 1px); background-size: 48px 48px; mask-image: linear-gradient(to bottom, black 0%, transparent 78%); }
.hero-pattern { position: absolute; inset: 0; pointer-events: none; }
.ghost-character { position: absolute; font-family: var(--font-serif); line-height: 1; color: rgba(47, 113, 96, 0.055); }
.ghost-one { top: 92px; left: -40px; font-size: 320px; transform: rotate(-8deg); }
.ghost-two { top: 150px; right: 4%; color: rgba(212, 85, 66, 0.055); font-size: 250px; transform: rotate(7deg); }
.ghost-three { top: 420px; right: -50px; font-size: 280px; }
.hero-inner { position: relative; z-index: 2; width: min(850px, calc(100% - 48px)); margin: auto; text-align: center; }
.eyebrow { display: flex; align-items: center; gap: 10px; margin-bottom: 18px; color: rgba(255,255,255,.7); font-size: 13px; font-weight: 700; letter-spacing: 0; text-transform: uppercase; }
.hero .eyebrow, .algorithm-section .eyebrow, .problem-band .eyebrow, .modules-section .eyebrow, .closing-section .eyebrow, .download-hero .eyebrow, .versions-section .eyebrow { justify-content: center; }
.hero .eyebrow { color: var(--red-dark); }
.eyebrow span { width: 24px; height: 1px; background: currentColor; }
.eyebrow-dark { color: var(--red-dark); }
.hero h1 { margin: 0; color: var(--ink); font-size: clamp(86px, 11vw, 150px); line-height: .92; }
.hero-lead { margin: 24px 0 8px; color: var(--ink); font-family: var(--font-serif); font-size: clamp(24px, 3.2vw, 38px); font-weight: 700; }
.hero-copy { max-width: 670px; margin: 0 auto; font-size: 17px; }
.hero-actions { display: flex; justify-content: center; gap: 12px; margin-top: 30px; }
.button { min-height: 48px; display: inline-flex; align-items: center; justify-content: center; gap: 18px; padding: 0 22px; border: 1px solid transparent; border-radius: 4px; font-size: 14px; font-weight: 700; cursor: pointer; transition: transform 160ms ease, background 160ms ease, color 160ms ease, border-color 160ms ease; }
.button:hover { transform: translateY(-2px); }
.button-primary { background: var(--red); color: white; }
.button-primary:hover { background: var(--red-dark); }
.button-app { background: #39a88c; }
.button-app:hover { background: #278874; }
.button-quiet, .button-secondary { border-color: var(--ink); background: transparent; color: var(--ink); }
.button-quiet:hover, .button-secondary:hover { background: var(--ink); color: white; }

.memory-stage { position: relative; z-index: 2; width: min(840px, calc(100% - 48px)); margin: 54px auto 0; padding: 24px 28px 18px; border: 1px solid #cfd5d0; border-radius: 8px 8px 0 0; background: rgba(255,255,255,.88); box-shadow: var(--shadow); backdrop-filter: blur(12px); }
.stage-topline { display: flex; justify-content: space-between; align-items: center; padding-bottom: 18px; border-bottom: 1px solid var(--line); }
.stage-topline > div:first-child { display: flex; flex-direction: column; align-items: flex-start; }
.stage-label, .stage-score span { color: #738078; font-size: 11px; }
.stage-topline strong { font-family: var(--font-serif); font-size: 18px; }
.stage-score { display: flex; align-items: baseline; gap: 9px; }
.stage-score strong { color: var(--green); font-family: var(--font-sans); font-size: 25px; }
.character-row { display: grid; grid-template-columns: repeat(5, 1fr); gap: 12px; padding: 22px 0; }
.character-row > span { position: relative; height: 74px; display: grid; place-items: center; border: 1px solid var(--line); border-radius: 6px; background-color: #fbfcfa; background-image: linear-gradient(transparent 49%, rgba(23,33,27,.07) 50%, transparent 51%), linear-gradient(90deg, transparent 49%, rgba(23,33,27,.07) 50%, transparent 51%); color: #818a83; font-family: var(--font-serif); font-size: 35px; }
.character-row .character-done { background-color: #e7f0eb; color: var(--green); }
.character-row .character-active { border: 2px solid var(--red); background-color: #fff6f4; color: var(--red); transform: translateY(-5px); }
.character-active i { position: absolute; right: 5px; bottom: 5px; width: 8px; height: 8px; border-radius: 50%; background: var(--red); }
.stage-progress { height: 4px; overflow: hidden; border-radius: 4px; background: #e4e7e4; }
.stage-progress span { display: block; height: 100%; border-radius: inherit; background: var(--red); }
.stage-days { display: grid; grid-template-columns: repeat(10, 1fr); margin-top: 9px; color: #909991; font-size: 10px; text-align: center; }
.stage-days .current { color: var(--red); font-weight: 700; }
.hero-metrics { position: relative; z-index: 3; width: var(--shell); margin: 0 auto; display: grid; grid-template-columns: repeat(3, 1fr); background: var(--ink); color: white; }
.hero-metrics div { min-height: 96px; display: flex; align-items: center; justify-content: center; gap: 12px; border-right: 1px solid rgba(255,255,255,.13); }
.hero-metrics div:last-child { border-right: 0; }
.hero-metrics strong { color: var(--gold); font-family: var(--font-serif); font-size: 34px; }
.hero-metrics span { color: rgba(255,255,255,.7); font-size: 13px; }

.problem-band { padding: 120px 0; background: var(--white); }
.section-heading h2 { margin: 0; font-size: clamp(38px, 5vw, 64px); }
.split-heading { display: grid; grid-template-columns: 1.1fr .9fr; align-items: end; gap: 100px; }
.split-heading .eyebrow { justify-content: flex-start; }
.split-heading > p { max-width: 480px; margin: 0 0 6px; font-size: 17px; }
.problem-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 54px; margin-top: 76px; }
.problem-grid article { padding-top: 22px; border-top: 1px solid var(--ink); }
.problem-index { color: var(--red); font-family: var(--font-serif); font-size: 14px; }
.problem-grid h3 { margin: 54px 0 14px; font-family: var(--font-serif); font-size: 25px; }
.problem-grid p { margin: 0; font-size: 14px; }

.algorithm-section { padding: 120px 0 130px; background: var(--mist); }
.centered-heading { max-width: 850px; margin: 0 auto 58px; text-align: center; }
.centered-heading p:last-child { max-width: 670px; margin: 22px auto 0; }
.algorithm-board { display: grid; grid-template-columns: 1fr 285px; min-height: 540px; overflow: hidden; border: 1px solid #cdd9d2; border-radius: 8px; background: white; box-shadow: 0 20px 70px rgba(24,63,53,.1); }
.curve-panel { padding: 38px 36px 30px; min-width: 0; }
.curve-header { display: flex; gap: 60px; }
.curve-header div { display: flex; flex-direction: column; gap: 4px; }
.curve-header span { color: #7c8981; font-size: 11px; }
.curve-header strong { font-family: var(--font-serif); font-size: 20px; }
.curve-visual { position: relative; margin-top: 26px; }
.curve-visual svg { width: 100%; }
.curve-line { fill: none; stroke: var(--red); stroke-width: 5; stroke-linecap: round; }
.curve-area { fill: url(#curveFill); }
.threshold { fill: none; stroke: #9cac9f; stroke-width: 1; stroke-dasharray: 7 7; }
.threshold-label { position: absolute; right: 0; bottom: 62px; color: #85928a; font-size: 10px; }
.node-picker { display: grid; grid-template-columns: repeat(10, minmax(44px, 1fr)); gap: 4px; margin-top: 3px; }
.node-button { position: relative; min-height: 60px; border: 0; background: transparent; color: #7d8780; font-size: 10px; cursor: pointer; }
.node-button i { position: absolute; top: 5px; left: 50%; width: 12px; height: 12px; transform: translateX(-50%); border: 2px solid var(--red); border-radius: 50%; background: white; }
.node-button span { display: block; padding-top: 24px; white-space: nowrap; }
.node-button.detection i { border-color: var(--green); }
.node-button.is-active i { box-shadow: 0 0 0 5px rgba(212,85,66,.15); background: var(--red); }
.node-button.detection.is-active i { box-shadow: 0 0 0 5px rgba(47,113,96,.15); background: var(--green); }
.node-button.is-active { color: var(--ink); font-weight: 700; }
.task-panel { display: flex; flex-direction: column; justify-content: space-between; padding: 34px 28px; background: var(--green-dark); color: white; }
.task-day { display: flex; align-items: baseline; justify-content: space-between; border-bottom: 1px solid rgba(255,255,255,.18); }
.task-day span { color: rgba(255,255,255,.48); font-size: 11px; }
.task-day strong { color: var(--gold); font-family: var(--font-serif); font-size: 74px; line-height: 1; }
.task-kicker { color: var(--gold); font-size: 12px; font-weight: 700; }
.task-panel h3 { margin: 10px 0 18px; font-family: var(--font-serif); font-size: 29px; }
.task-panel p { margin: 0; color: rgba(255,255,255,.67); font-size: 13px; }
.task-meter { display: grid; grid-template-columns: 1fr auto; gap: 10px; align-items: center; }
.task-meter span { color: rgba(255,255,255,.5); font-size: 10px; }
.task-meter div { grid-column: 1 / 2; height: 5px; overflow: hidden; border-radius: 5px; background: rgba(255,255,255,.14); }
.task-meter i { display: block; height: 100%; background: var(--gold); transition: width 220ms ease; }
.task-meter strong { grid-row: 1 / 3; grid-column: 2; color: var(--gold); font-size: 20px; }

.modules-section { padding: 120px 0; background: var(--paper); }
.compact-heading h2 { font-size: clamp(38px, 4vw, 55px); }
.module-grid { display: grid; grid-template-columns: repeat(6, 1fr); gap: 12px; margin-top: 70px; }
.module-grid article { grid-column: span 2; min-height: 325px; display: flex; flex-direction: column; justify-content: space-between; padding: 26px; border: 1px solid var(--line); border-radius: 6px; background: white; transition: transform 180ms ease, box-shadow 180ms ease; }
.module-grid article:hover { transform: translateY(-5px); box-shadow: 0 18px 45px rgba(23,33,27,.08); }
.module-grid .module-feature { grid-column: span 3; }
.module-grid article:nth-child(2) { grid-column: span 3; background: var(--ink); color: white; }
.module-grid article:nth-child(4) { grid-column: span 3; }
.module-grid article:nth-child(5) { grid-column: span 3; background: var(--red); color: white; }
.module-character { align-self: flex-end; color: var(--red); font-family: var(--font-serif); font-size: 82px; line-height: 1; opacity: .85; }
.module-grid article:nth-child(2) .module-character { color: var(--gold); }
.module-grid article:nth-child(5) .module-character { color: white; opacity: .3; }
.module-grid article div > span { color: var(--red); font-size: 11px; }
.module-grid article:nth-child(2) div > span, .module-grid article:nth-child(5) div > span { color: var(--gold); }
.module-grid h3 { margin: 10px 0 9px; font-family: var(--font-serif); font-size: 24px; }
.module-grid p { margin: 0; font-size: 13px; }
.module-grid article:nth-child(2) p, .module-grid article:nth-child(5) p { color: rgba(255,255,255,.68); }

.app-section { padding: 120px 0; overflow: hidden; background: white; }
.app-layout { display: grid; grid-template-columns: .8fr 1.2fr; align-items: center; gap: 110px; }
.app-visual { position: relative; min-height: 720px; display: grid; place-items: center; }
.app-visual::before { content: ""; position: absolute; width: 520px; height: 520px; border-radius: 50%; background: #e5f5ed; }
.app-visual::after { content: "字"; position: absolute; top: 58px; right: 3%; color: rgba(212,85,66,.13); font-family: var(--font-serif); font-size: 110px; }
.app-phone { position: relative; z-index: 1; width: 330px; height: 672px; overflow: hidden; border: 10px solid #26312b; border-radius: 38px; background: white; box-shadow: 0 35px 70px rgba(23,33,27,.22); }
.app-phone-top { position: absolute; z-index: 3; top: 0; right: 0; left: 0; height: 23px; background: #26312b; }
.app-phone-top span { position: absolute; top: 8px; left: 50%; width: 58px; height: 5px; transform: translateX(-50%); border-radius: 5px; background: #59645e; }
.app-phone img { width: 100%; height: 100%; padding-top: 17px; object-fit: cover; object-position: top center; }
.app-visual-note { position: absolute; z-index: 2; right: 4%; bottom: 74px; padding: 8px 12px; border-radius: 4px; background: var(--gold); color: var(--ink); font-size: 11px; font-weight: 700; }
.app-content .eyebrow { justify-content: flex-start; }
.app-content h2 { margin: 0; font-size: clamp(48px, 5vw, 70px); }
.app-lead { max-width: 620px; margin: 22px 0 38px; font-family: var(--font-serif); font-size: 23px; }
.app-feature-list { display: grid; grid-template-columns: 1fr 1fr; margin-bottom: 34px; border-top: 1px solid var(--line); border-left: 1px solid var(--line); }
.app-feature-list > div { min-height: 180px; padding: 22px; border-right: 1px solid var(--line); border-bottom: 1px solid var(--line); }
.app-feature-list strong { color: var(--red); font-size: 10px; }
.app-feature-list h3 { margin: 30px 0 8px; font-family: var(--font-serif); font-size: 22px; }
.app-feature-list p { margin: 0; font-size: 12px; }

.workflow-section { padding: 120px 0; background: var(--ink); color: white; }
.workflow-section .section-shell { display: grid; grid-template-columns: .75fr 1.25fr; gap: 100px; }
.workflow-intro { position: sticky; top: 120px; align-self: start; }
.workflow-intro h2 { margin: 0; font-size: clamp(40px, 5vw, 62px); }
.workflow-intro h2 strong { display: block; color: var(--gold); font-size: 1.9em; line-height: .9; }
.workflow-intro > p:last-child { margin: 24px 0 0; color: rgba(255,255,255,.58); }
.workflow-list { margin: 0; padding: 0; list-style: none; }
.workflow-list li { min-height: 126px; display: grid; grid-template-columns: 56px 1fr auto; align-items: center; gap: 24px; border-top: 1px solid rgba(255,255,255,.16); }
.workflow-list li:last-child { border-bottom: 1px solid rgba(255,255,255,.16); }
.workflow-number { color: var(--gold); font-size: 11px; }
.workflow-list h3 { margin: 0 0 5px; font-family: var(--font-serif); font-size: 22px; }
.workflow-list p { margin: 0; color: rgba(255,255,255,.52); font-size: 13px; }
.workflow-list li > strong { color: rgba(255,255,255,.76); font-size: 13px; font-weight: 500; }

.closing-section { padding: 110px 0; background: var(--gold); }
.closing-inner { display: flex; align-items: flex-end; justify-content: space-between; gap: 60px; }
.closing-inner .eyebrow { justify-content: flex-start; color: var(--ink); }
.closing-inner h2 { max-width: 820px; margin: 0; font-size: clamp(40px, 5vw, 64px); }
.closing-inner .button-primary { flex: none; background: var(--ink); }

.site-footer { padding: 54px 0 30px; background: #101713; color: white; }
.footer-shell { width: var(--shell); margin: auto; display: grid; grid-template-columns: auto 1fr auto; align-items: center; gap: 40px; }
.brand-footer .brand-mark { color: white; }
.footer-shell p { margin: 0; color: rgba(255,255,255,.44); font-size: 12px; }
.footer-shell > div { display: flex; gap: 22px; font-size: 12px; color: rgba(255,255,255,.65); }
.footer-shell > div a:hover { color: white; }
.footer-shell small { grid-column: 1 / -1; padding-top: 22px; border-top: 1px solid rgba(255,255,255,.1); color: rgba(255,255,255,.32); font-size: 11px; }

/* Download page */
.download-page { background: var(--paper); }
.download-hero { padding: 150px 0 110px; }
.download-heading { max-width: 800px; margin-bottom: 58px; }
.download-heading .eyebrow { justify-content: flex-start; }
.download-heading h1 { margin: 0; font-size: clamp(52px, 7vw, 84px); }
.download-heading > p:last-child { max-width: 660px; margin: 24px 0 0; font-size: 17px; }
.device-switcher { scroll-margin-top: 96px; border: 1px solid var(--line); border-radius: 8px; background: white; box-shadow: var(--shadow); }
.device-tabs { display: grid; grid-template-columns: repeat(3, 1fr); border-bottom: 1px solid var(--line); }
.device-tabs button { min-height: 70px; border: 0; border-right: 1px solid var(--line); background: #f4f5f1; color: #7b857e; cursor: pointer; }
.device-tabs button:last-child { border-right: 0; }
.device-tabs button.is-active { position: relative; background: white; color: var(--ink); font-weight: 700; }
.device-tabs button.is-active::after { content: ""; position: absolute; right: 24px; bottom: 0; left: 24px; height: 3px; background: var(--red); }
.device-symbol { display: inline-block; margin-right: 7px; color: var(--green); font-size: 20px; transform: translateY(1px); }
.tablet-symbol { transform: translateY(1px) rotate(90deg); }
.mobile-symbol { font-size: 17px; }
.device-panel { min-height: 500px; display: grid; grid-template-columns: .8fr 1.2fr; align-items: center; gap: 50px; padding: 48px 48px 0; overflow: hidden; }
.device-panel[hidden] { display: none; }
.status-badge { display: inline-flex; align-items: center; min-height: 28px; padding: 0 10px; border-radius: 20px; font-size: 11px; font-weight: 700; }
.status-ready { background: #e5f0eb; color: var(--green); }
.status-building { background: #fff0d7; color: #9a6613; }
.device-copy { padding-bottom: 48px; }
.device-copy h2 { margin: 18px 0 14px; font-size: 48px; }
.device-copy > p { margin-bottom: 28px; }
.device-copy dl { margin: 0 0 30px; }
.device-copy dl div { display: grid; grid-template-columns: 80px 1fr; gap: 12px; padding: 9px 0; border-top: 1px solid var(--line); font-size: 12px; }
.device-copy dt { color: #8b958e; }
.device-copy dd { margin: 0; color: var(--ink); }
.device-preview { position: relative; align-self: end; justify-self: center; width: 100%; }
.desktop-preview { height: 390px; border: 9px solid #29332d; border-bottom-width: 24px; border-radius: 8px 8px 3px 3px; background: #eef1ee; box-shadow: 0 32px 55px rgba(23,33,27,.2); }
.desktop-preview::after { content: ""; position: absolute; left: 22%; right: 22%; bottom: -52px; height: 28px; background: #29332d; clip-path: polygon(7% 0, 93% 0, 100% 100%, 0 100%); }
.preview-toolbar { height: 28px; display: flex; align-items: center; gap: 6px; padding: 0 10px; background: #dfe4df; }
.preview-toolbar i { width: 6px; height: 6px; border-radius: 50%; background: #aeb7b0; }
.preview-toolbar i:first-child { background: var(--red); }
.preview-toolbar span { margin-left: auto; color: #77827a; font-size: 8px; }
.preview-body { height: calc(100% - 28px); display: grid; grid-template-columns: 96px 1fr; }
.preview-side { display: flex; flex-direction: column; gap: 14px; padding: 18px; background: var(--green-dark); color: white; }
.preview-side strong { margin-bottom: 14px; font-family: var(--font-serif); }
.preview-side span { width: 44px; height: 5px; border-radius: 4px; background: rgba(255,255,255,.18); }
.preview-side .selected { width: 58px; background: var(--gold); }
.preview-main { padding: 26px; }
.preview-meta { display: flex; justify-content: space-between; color: #6f7d74; font-size: 9px; }
.preview-meta strong { color: var(--red); }
.preview-character { width: 160px; height: 160px; margin: 30px auto 20px; display: grid; place-items: center; border: 1px solid #cad2cc; background-image: linear-gradient(transparent 49%, #e1e6e2 50%, transparent 51%), linear-gradient(90deg, transparent 49%, #e1e6e2 50%, transparent 51%); color: var(--ink); font-family: var(--font-serif); font-size: 85px; }
.preview-words { display: flex; justify-content: center; gap: 8px; }
.preview-words span { padding: 5px 10px; border-radius: 3px; background: white; color: #78847c; font-size: 8px; }
.tablet-preview { max-width: 440px; height: 390px; padding: 10px; border: 12px solid #26312b; border-radius: 20px 20px 0 0; background: #26312b; box-shadow: 0 32px 55px rgba(23,33,27,.2); }
.tablet-camera { position: absolute; top: 5px; left: 50%; width: 4px; height: 4px; border-radius: 50%; background: #69756d; }
.tablet-screen { height: 100%; display: flex; flex-direction: column; align-items: center; padding: 30px; background: #edf2ee; }
.tablet-screen > span { align-self: flex-start; color: var(--green); font-size: 10px; }
.tablet-screen > strong { width: 210px; height: 210px; margin: 25px 0 18px; display: grid; place-items: center; border: 1px solid #c4d2c9; background: white; color: var(--red); font-family: var(--font-serif); font-size: 105px; }
.tablet-screen > div { display: flex; gap: 8px; }
.tablet-screen i { display: block; width: 50px; height: 7px; border-radius: 4px; background: #cbd6cf; }
.phone-preview { max-width: 270px; height: 430px; padding: 10px; border: 10px solid #26312b; border-bottom: 0; border-radius: 34px 34px 0 0; background: #26312b; box-shadow: 0 32px 55px rgba(23,33,27,.2); }
.phone-speaker { position: absolute; z-index: 2; top: 16px; left: 50%; width: 60px; height: 5px; transform: translateX(-50%); border-radius: 5px; background: #26312b; }
.phone-screen { height: 100%; display: flex; flex-direction: column; align-items: center; padding: 54px 20px 20px; border-radius: 20px 20px 0 0; background: #edf2ee; }
.phone-screen span { color: var(--green); font-size: 11px; }
.phone-screen strong { margin-top: 32px; color: var(--red); font-family: var(--font-serif); font-size: 100px; line-height: 1; }
.phone-screen small { color: #718077; }
.phone-ring { width: 130px; height: 130px; margin-top: -98px; border: 8px solid rgba(212,85,66,.14); border-top-color: var(--red); border-radius: 50%; transform: rotate(45deg); }
.phone-screen i { width: 150px; height: 44px; margin-top: 54px; border-radius: 4px; background: var(--green-dark); }
.phone-screen.app-live-screen { display: block; padding: 0; overflow: hidden; background: white; }
.phone-screen.app-live-screen img { width: 100%; height: 100%; object-fit: cover; object-position: top center; }

.versions-section { padding: 120px 0; background: white; }
.version-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 14px; margin-top: 64px; }
.version-card { position: relative; min-height: 530px; display: flex; flex-direction: column; padding: 30px; border: 1px solid var(--line); border-radius: 6px; background: var(--paper); }
.version-number { color: var(--red); font-size: 12px; }
.version-card h3 { margin: 22px 0 10px; font-family: var(--font-serif); font-size: 31px; }
.version-card > div p { min-height: 54px; margin: 0; font-size: 14px; }
.version-card ul { margin: 36px 0; padding: 0; list-style: none; }
.version-card li { position: relative; padding: 10px 0 10px 24px; border-top: 1px solid var(--line); color: #3f4c44; font-size: 13px; }
.version-card li::before { content: "✓"; position: absolute; left: 0; color: var(--green); font-weight: 700; }
.version-card li.muted { color: #919a94; }
.version-card li.muted::before { content: "–"; color: #919a94; }
.version-card .button { width: 100%; margin-top: auto; }
.featured-version { border-color: var(--green-dark); background: var(--green-dark); color: white; box-shadow: 0 18px 45px rgba(24,63,53,.16); }
.featured-version p, .featured-version li { color: rgba(255,255,255,.68); }
.featured-version li { border-color: rgba(255,255,255,.15); }
.featured-version li::before { color: var(--gold); }
.recommend-label { position: absolute; top: 0; right: 0; padding: 7px 12px; background: var(--gold); color: var(--ink); font-size: 10px; font-weight: 700; }

.requirements-section { padding: 100px 0; background: var(--red); color: white; }
.requirements-layout { display: grid; grid-template-columns: .8fr 1.2fr; gap: 90px; align-items: center; }
.requirements-layout h2 { margin: 0; font-size: 52px; }
.requirements-list { display: grid; grid-template-columns: repeat(3, 1fr); gap: 12px; }
.requirements-list div { min-height: 150px; display: flex; flex-direction: column; justify-content: space-between; padding: 20px; border: 1px solid rgba(255,255,255,.3); border-radius: 5px; }
.requirements-list strong { color: var(--gold); font-size: 12px; }
.requirements-list span { font-family: var(--font-serif); font-size: 18px; }

.request-dialog { width: min(560px, calc(100% - 32px)); max-height: calc(100vh - 32px); overflow-y: auto; padding: 34px; border: 0; border-radius: 8px; background: var(--paper); box-shadow: 0 30px 100px rgba(0,0,0,.3); }
.request-dialog::backdrop { background: rgba(14,21,17,.72); backdrop-filter: blur(5px); }
.dialog-close { position: absolute; top: 18px; right: 18px; width: 34px; height: 34px; border: 0; background: transparent; font-size: 26px; cursor: pointer; }
.dialog-heading { display: flex; align-items: center; gap: 16px; padding-right: 35px; margin-bottom: 30px; }
.dialog-heading p { margin: 0; color: var(--red); font-size: 11px; }
.dialog-heading h2 { margin: 2px 0 0; font-size: 30px; }
.request-dialog form { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; }
.request-dialog label { display: flex; flex-direction: column; gap: 6px; color: #5a675f; font-size: 12px; }
.request-dialog label:nth-of-type(3), .request-dialog label:nth-of-type(4), .dialog-submit, .form-note { grid-column: 1 / -1; }
.request-dialog input, .request-dialog select, .request-dialog textarea { width: 100%; border: 1px solid #ccd2cd; border-radius: 4px; background: white; padding: 11px 12px; color: var(--ink); outline: none; }
.request-dialog input:focus, .request-dialog select:focus, .request-dialog textarea:focus { border-color: var(--green); box-shadow: 0 0 0 3px rgba(47,113,96,.1); }
.request-dialog textarea { resize: vertical; }
.dialog-submit { margin-top: 8px; }
.form-note { margin: -4px 0 0; text-align: center; font-size: 10px; }
.dialog-success { padding: 20px 0 10px; text-align: center; }
.dialog-success > span { width: 64px; height: 64px; display: grid; place-items: center; margin: 0 auto 20px; border-radius: 50%; background: var(--green); color: white; font-size: 28px; }
.dialog-success h2 { font-size: 34px; }
.dialog-success p { max-width: 400px; margin: 0 auto 26px; }

@media (max-width: 960px) {
  :root { --shell: min(100% - 36px, 760px); }
  .desktop-nav, .nav-cta { display: none; }
  .menu-button { display: block; }
  .mobile-nav { position: fixed; top: 76px; right: 0; bottom: 0; left: 0; display: flex; flex-direction: column; padding: 28px 18px; transform: translateX(100%); background: var(--paper); transition: transform 200ms ease; }
  .mobile-nav.is-open { transform: translateX(0); }
  .mobile-nav a { padding: 18px 4px; border-bottom: 1px solid var(--line); font-family: var(--font-serif); font-size: 24px; }
  .hero { min-height: auto; padding-top: 132px; }
  .memory-stage { margin-top: 44px; }
  .hero-metrics { width: 100%; }
  .split-heading { grid-template-columns: 1fr; gap: 24px; }
  .problem-grid { gap: 24px; }
  .algorithm-board { grid-template-columns: 1fr; }
  .task-panel { min-height: 300px; display: grid; grid-template-columns: 1fr 1.4fr; gap: 30px; }
  .task-meter { grid-column: 1 / -1; }
  .module-grid { grid-template-columns: repeat(2, 1fr); }
  .module-grid article, .module-grid .module-feature, .module-grid article:nth-child(2), .module-grid article:nth-child(4), .module-grid article:nth-child(5) { grid-column: span 1; }
  .module-grid article:last-child { grid-column: 1 / -1; }
  .app-layout { grid-template-columns: 1fr; gap: 55px; }
  .app-visual { order: 2; min-height: 700px; }
  .workflow-section .section-shell { grid-template-columns: 1fr; gap: 60px; }
  .workflow-intro { position: static; }
  .closing-inner { align-items: flex-start; flex-direction: column; }
  .footer-shell { grid-template-columns: auto 1fr; }
  .footer-shell > div { grid-column: 1 / -1; }
  .device-panel { grid-template-columns: 1fr; padding-bottom: 0; }
  .device-copy { padding-bottom: 0; }
  .device-preview { max-width: 560px; }
  .version-grid { grid-template-columns: 1fr; }
  .version-card { min-height: 0; }
  .requirements-layout { grid-template-columns: 1fr; gap: 45px; }
}

@media (max-width: 640px) {
  :root { --shell: calc(100% - 28px); }
  body { font-size: 15px; }
  .nav-shell { min-height: 68px; }
  .menu-button { position: absolute; top: 13px; right: 14px; z-index: 2; display: block; }
  .mobile-nav { top: 68px; }
  .brand-mark { width: 34px; height: 34px; font-size: 21px; }
  .brand-name { font-size: 20px; }
  .hero { padding-top: 118px; }
  .hero-inner { width: calc(100% - 28px); }
  .hero h1 { font-size: 76px; }
  .hero-lead { max-width: 330px; margin-inline: auto; font-size: 22px; line-height: 1.45; overflow-wrap: anywhere; }
  .hero-copy { font-size: 15px; }
  .hero-actions { align-items: stretch; flex-direction: column; width: 100%; }
  .memory-stage { width: calc(100% - 28px); padding: 18px 16px 14px; }
  .stage-topline strong { font-size: 15px; }
  .stage-score { flex-direction: column; align-items: flex-end; gap: 0; }
  .stage-score strong { font-size: 20px; }
  .character-row { gap: 6px; }
  .character-row > span { height: 55px; font-size: 27px; }
  .hero-metrics { margin-top: 0; }
  .hero-metrics div { min-height: 88px; flex-direction: column; gap: 0; text-align: center; }
  .hero-metrics strong { font-size: 28px; }
  .hero-metrics span { max-width: 70px; font-size: 10px; line-height: 1.3; }
  .problem-band, .algorithm-section, .modules-section, .workflow-section, .versions-section { padding: 84px 0; }
  .section-heading h2, .compact-heading h2 { font-size: 38px; }
  .problem-grid { grid-template-columns: 1fr; margin-top: 48px; }
  .problem-grid h3 { margin-top: 26px; }
  .centered-heading { text-align: left; }
  .hero .eyebrow, .algorithm-section .eyebrow, .problem-band .eyebrow, .modules-section .eyebrow, .closing-section .eyebrow, .download-hero .eyebrow, .versions-section .eyebrow { justify-content: flex-start; }
  .curve-panel { padding: 26px 14px; overflow-x: auto; }
  .curve-header { gap: 30px; }
  .curve-visual, .node-picker { min-width: 640px; }
  .task-panel { display: flex; min-height: 360px; }
  .task-day strong { font-size: 60px; }
  .module-grid { grid-template-columns: 1fr; }
  .module-grid article, .module-grid .module-feature, .module-grid article:nth-child(2), .module-grid article:nth-child(4), .module-grid article:nth-child(5), .module-grid article:last-child { grid-column: auto; min-height: 270px; }
  .app-section { padding: 84px 0; }
  .app-layout { gap: 46px; }
  .app-content h2 { font-size: 42px; }
  .app-lead { font-size: 20px; }
  .app-feature-list { grid-template-columns: 1fr; }
  .app-feature-list > div { min-height: 145px; }
  .app-visual { min-height: 640px; }
  .app-visual::before { width: 420px; height: 420px; }
  .app-phone { width: 300px; height: 610px; }
  .app-visual-note { right: 2%; bottom: 44px; }
  .workflow-section .section-shell { gap: 44px; }
  .workflow-intro h2 { font-size: 40px; }
  .workflow-list li { grid-template-columns: 38px 1fr; gap: 14px; padding: 18px 0; }
  .workflow-list li > strong { grid-column: 2; }
  .closing-section { padding: 80px 0; }
  .closing-inner h2 { font-size: 39px; }
  .footer-shell { display: flex; align-items: flex-start; flex-direction: column; gap: 22px; }
  .footer-shell > div { flex-wrap: wrap; }
  .footer-shell small { width: 100%; }
  .download-hero { padding: 120px 0 80px; }
  .download-heading h1 { font-size: 38px; line-height: 1.3; overflow-wrap: anywhere; }
  .device-tabs button { min-height: 62px; font-size: 12px; }
  .device-symbol { display: none; }
  .device-panel { min-height: 0; gap: 24px; padding: 30px 20px 0; }
  .device-copy h2 { font-size: 40px; }
  .desktop-preview { height: 280px; border-width: 7px; border-bottom-width: 17px; }
  .desktop-preview::after { bottom: -37px; height: 20px; }
  .preview-body { grid-template-columns: 62px 1fr; }
  .preview-side { padding: 12px 8px; }
  .preview-side strong { font-size: 10px; }
  .preview-main { padding: 16px; }
  .preview-character { width: 120px; height: 120px; margin-top: 22px; font-size: 64px; }
  .tablet-preview { height: 340px; }
  .tablet-screen > strong { width: 180px; height: 180px; }
  .version-grid { margin-top: 42px; }
  .requirements-section { padding: 76px 0; }
  .requirements-layout h2 { font-size: 40px; }
  .requirements-list { grid-template-columns: 1fr; }
  .requirements-list div { min-height: 100px; }
  .request-dialog { padding: 28px 20px; }
  .request-dialog form { grid-template-columns: 1fr; }
  .request-dialog label, .request-dialog label:nth-of-type(3), .request-dialog label:nth-of-type(4), .dialog-submit, .form-note { grid-column: auto; }
}

/* Introduction page */
.sr-only { position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px; overflow: hidden; clip-path: inset(50%); white-space: nowrap; border: 0; }
:focus-visible { outline: 3px solid var(--green); outline-offset: 5px; }
.intro-page section[id] { scroll-margin-top: 95px; }
.intro-page .hero { min-height: auto; padding-top: 150px; }
.hero-layout { position: relative; z-index: 2; display: grid; grid-template-columns: 1fr 1fr; align-items: center; gap: 72px; padding-bottom: 76px; }
.intro-page .hero-inner { width: 100%; margin: 0; text-align: left; }
.intro-page .hero .eyebrow { justify-content: flex-start; }
.intro-page .hero h1 { font-size: clamp(80px, 8vw, 112px); }
.intro-page .hero-lead { margin: 28px 0 18px; font-size: clamp(26px, 3vw, 36px); line-height: 1.5; }
.intro-page .hero-copy { max-width: 460px; margin: 0; font-size: 16px; line-height: 1.9; }
.intro-page .hero-actions { justify-content: flex-start; }
.hero-tags { display: flex; gap: 24px; padding: 0; margin: 28px 0 0; list-style: none; color: var(--ink-soft); font-size: 12px; }
.hero-tags li::before { content: "✓"; margin-right: 7px; color: var(--green); }
.study-preview { transform: rotate(1.5deg); overflow: hidden; border: 1px solid #cad7ce; border-radius: 14px; background: white; box-shadow: 0 24px 65px #183f3514; }
.preview-caption { display: flex; justify-content: space-between; align-items: center; gap: 12px; padding: 17px 24px; border-bottom: 1px solid var(--line); background: #eff4ee; font-size: 12px; }
.preview-caption > span { display: flex; align-items: center; gap: 9px; font-weight: 700; }
.preview-caption i { width: 7px; height: 7px; border-radius: 50%; background: var(--green); }
.preview-caption small { color: #59695d; font-size: 10px; }
.study-preview-body { padding: 30px 26px 22px; }
.preview-overline { margin-bottom: 9px; color: var(--green); font-size: 11px; }
.study-preview h2 { margin-bottom: 23px; font-size: 25px; line-height: 1.4; }
.preview-filters { display: flex; flex-wrap: wrap; gap: 8px; }
.preview-filters span { padding: 5px 10px; border: 1px solid var(--line); border-radius: 4px; color: var(--ink-soft); font-size: 11px; }
.preview-categories { display: flex; gap: 24px; margin-top: 25px; border-bottom: 1px solid var(--line); font-size: 12px; color: #6b766f; }
.preview-categories span { padding-bottom: 10px; }
.preview-categories .selected { border-bottom: 2px solid var(--green); color: var(--green); font-weight: 700; }
.preview-character-grid { display: grid; grid-template-columns: repeat(5, minmax(0, 1fr)); gap: 8px; margin-top: 22px; }
.preview-character-grid > span { display: flex; flex-direction: column; align-items: center; padding: 12px 0 9px; border: 1px solid #d5e4d9; border-radius: 5px; background: #f1f7f1; color: var(--green); font-family: var(--font-serif); font-size: 33px; line-height: 1.5; }
.preview-character-grid small { font-family: var(--font-sans); font-size: 11px; }
.preview-character-grid .needs-practice { border-color: #ecc6b9; background: #fcf1eb; color: var(--red-dark); }
.preview-key { display: flex; flex-wrap: wrap; gap: 18px; margin-top: 15px; color: #66736a; font-size: 10px; }
.preview-key span { display: inline-flex; align-items: center; gap: 5px; }
.preview-key i { width: 5px; height: 5px; border-radius: 50%; background: var(--green); }
.preview-key span:last-child i { background: var(--red); }
.preview-next { display: flex; align-items: center; gap: 12px; margin-top: 25px; padding-top: 20px; border-top: 1px solid var(--line); }
.preview-next-icon { display: grid; place-items: center; width: 40px; height: 40px; border-radius: 8px; background: var(--green-dark); color: var(--gold); font-family: var(--font-serif); font-size: 24px; }
.preview-next strong { display: block; font-size: 12px; }
.preview-next p { margin: 3px 0 0; font-size: 10px; }
.preview-next > span:last-child { margin-left: auto; color: var(--green); }
.intro-page .hero-metrics { width: 100%; }
.intro-page .problem-band, .intro-page .algorithm-section, .intro-page .modules-section, .intro-page .app-section, .intro-page .workflow-section { padding: 96px 0; }
.intro-page .section-heading h2 { font-size: clamp(34px, 4vw, 52px); line-height: 1.35; }
.intro-page .problem-grid { margin-top: 52px; }
.intro-page .problem-grid h3 { margin-top: 36px; }
.intro-page .module-grid { margin-top: 48px; grid-template-columns: repeat(6, minmax(0, 1fr)); }
.intro-page .module-grid .module-feature, .intro-page .module-grid article:nth-child(2) { grid-column: span 3; }
.intro-page .module-grid article:nth-child(n+3) { grid-column: span 2; }
.intro-page .module-grid article { min-height: 280px; }
.intro-page .module-grid p { line-height: 1.9; }
.intro-page .module-character { font-size: 64px; }
.intro-page .app-layout { display: block; }
.intro-page .app-section .eyebrow { justify-content: center; }
.feature-tabs { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); border-bottom: 1px solid var(--line); }
.feature-tabs button { min-height: 76px; display: flex; justify-content: center; align-items: center; gap: 14px; border: 0; border-bottom: 3px solid transparent; background: transparent; color: #6e7c72; font-size: 11px; cursor: pointer; }
.feature-tabs button span { font-size: 17px; }
.feature-tabs button:hover { background: #f4f7f2; color: var(--green); }
.feature-tabs button.is-active { border-bottom-color: var(--green); background: #eff4ee; color: var(--green-dark); font-weight: 700; }
.feature-panel { display: grid; grid-template-columns: 1fr 1fr; gap: 80px; align-items: center; min-height: 580px; padding: 52px; border: 1px solid var(--line); border-top: 0; border-radius: 0 0 8px 8px; background: #fafbf7; }
.feature-panel[hidden] { display: none; }
.feature-kicker { color: var(--green); font-size: 12px; font-weight: 700; }
.feature-copy h3 { margin: 17px 0 22px; font-family: var(--font-serif); font-size: 35px; line-height: 1.5; }
.feature-copy > p { font-size: 14px; line-height: 1.9; }
.feature-copy ol { counter-reset: feature-step; margin: 27px 0; padding: 0; list-style: none; }
.feature-copy li { counter-increment: feature-step; display: flex; align-items: center; gap: 12px; margin-top: 13px; color: var(--ink-soft); font-size: 13px; }
.feature-copy li::before { content: counter(feature-step); display: grid; place-items: center; flex: none; width: 22px; height: 22px; border: 1px solid #cbd8ce; border-radius: 50%; color: var(--green); font-size: 10px; }
.feature-footnote { display: block; padding-top: 17px; border-top: 1px solid var(--line); color: #6c786f; font-size: 11px; }
.feature-demo { min-width: 0; padding: 24px; border: 1px solid #d5ddd6; border-radius: 10px; background: white; box-shadow: 0 15px 35px #183f350a; }
.demo-title { display: flex; justify-content: space-between; align-items: center; gap: 10px; padding-bottom: 17px; border-bottom: 1px solid var(--line); }
.demo-title strong { font-size: 14px; }
.demo-title > span { flex: none; color: #6b776e; font-size: 10px; }
.demo-filter-line { margin: 20px 0; color: var(--ink-soft); font-size: 11px; }
.demo-filter-line span { margin: 0 9px; color: #b9c5bb; }
.demo-study-card { display: flex; flex-direction: column; align-items: center; padding: 15px 0; }
.demo-pinyin { color: var(--green); font-size: 18px; }
.demo-study-card > strong { display: grid; place-items: center; width: 138px; height: 138px; margin: 10px 0; border: 1px solid #d6dfd7; background-color: #fafbf6; background-image: linear-gradient(transparent 49.5%, #e0e7de 49.5%, #e0e7de 50.5%, transparent 50.5%), linear-gradient(90deg, transparent 49.5%, #e0e7de 49.5%, #e0e7de 50.5%, transparent 50.5%); font-family: var(--font-serif); font-size: 88px; line-height: 1; }
.demo-study-card > span:last-of-type { color: var(--ink-soft); font-size: 12px; }
.demo-analysis { display: flex; gap: 22px; margin-top: 18px; color: #68756b; font-size: 10px; }
.demo-choice, .demo-export { display: flex; justify-content: center; gap: 12px; margin-top: 15px; }
.demo-choice span { width: 50%; padding: 8px; border: 1px solid #e9c9bd; border-radius: 4px; background: #fcf4ee; color: var(--red-dark); text-align: center; font-size: 12px; }
.demo-choice span:last-child { border-color: #c8dfd1; background: #eff6f0; color: var(--green); }
.demo-note { margin: 18px 0 0; text-align: center; color: #69766d; font-size: 10px; }
.demo-pills { display: flex; gap: 10px; margin: 24px 0; }
.demo-pills span { padding: 7px 13px; border-radius: 4px; color: var(--ink-soft); background: var(--paper); font-size: 12px; }
.demo-pills .selected { color: white; background: var(--green); }
.demo-field { margin: 20px 0; padding: 16px; border: 1px solid var(--line); border-radius: 5px; }
.demo-field > span { display: block; margin-bottom: 12px; color: #6c786f; font-size: 11px; }
.demo-field strong { font-family: var(--font-serif); font-size: 28px; }
.demo-field p { margin: 0; font-size: 13px; }
.demo-saved { display: flex; align-items: center; gap: 9px; padding: 14px; border-radius: 4px; background: #eef5ee; color: var(--green); font-size: 12px; }
.demo-calendar-heading { display: flex; flex-wrap: wrap; gap: 6px 20px; justify-content: space-between; margin: 24px 0 18px; font-size: 13px; }
.demo-calendar-heading span { color: var(--green); font-size: 11px; }
.demo-calendar { display: grid; grid-template-columns: repeat(5, minmax(0, 1fr)); gap: 8px; }
.demo-calendar > span { display: flex; flex-direction: column; align-items: center; padding: 12px 0; border: 1px solid var(--line); border-radius: 5px; font-size: 20px; }
.demo-calendar small { margin-top: 3px; color: #6c786f; font-size: 9px; }
.demo-calendar .selected { border-color: var(--green); background: var(--green-dark); color: white; }
.demo-calendar .selected small { color: #e4dfb8; }
.demo-review-row { display: flex; justify-content: space-between; gap: 8px; margin-top: 20px; padding-bottom: 12px; border-bottom: 1px solid var(--line); color: var(--ink-soft); font-size: 11px; }
.demo-review-row strong { color: var(--green); font-weight: 500; }
.demo-paper { display: flex; flex-direction: column; align-items: center; padding: 30px 0; }
.demo-paper > span { color: var(--ink-soft); font-size: 12px; }
.demo-paper strong { margin: 25px 0; color: var(--green); font-size: 29px; font-weight: 500; }
.demo-answer-boxes { display: flex; gap: 12px; }
.demo-answer-boxes i { width: 70px; height: 70px; border: 1px solid #b4c5b7; background-image: linear-gradient(transparent 49%, #e0e7de 50%, transparent 51%), linear-gradient(90deg, transparent 49%, #e0e7de 50%, transparent 51%); }
.demo-paper small { margin-top: 24px; color: #6c786f; font-size: 11px; }
.demo-export span { flex: 1; padding: 10px 5px; border: 1px solid #cbd8ce; border-radius: 4px; background: #f6f8f3; color: var(--green); text-align: center; font-size: 11px; }
.support-grid { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 36px; margin-top: 52px; }
.support-grid article { padding-top: 22px; border-top: 1px solid var(--line); }
.support-grid article > span { color: var(--red-dark); font-size: 11px; }
.support-grid h3 { margin: 18px 0 12px; font-family: var(--font-serif); font-size: 22px; line-height: 1.4; }
.support-grid p { margin: 0; font-size: 13px; line-height: 1.9; }
.matching-section { padding: 96px 0; background: white; }
.matching-table-wrap { margin-top: 42px; overflow-x: auto; border: 1px solid var(--line); border-radius: 7px; }
.matching-table { width: 100%; border-collapse: collapse; text-align: left; font-size: 14px; }
.matching-table th, .matching-table td { padding: 22px 28px; border-bottom: 1px solid var(--line); }
.matching-table thead { background: #edf3ed; }
.matching-table small { display: block; margin-top: 5px; color: #67746b; font-size: 11px; font-weight: 400; }
.matching-table tbody th { font-weight: 400; color: var(--ink-soft); }
.matching-table tr:last-child td, .matching-table tbody tr:last-child th { border-bottom: 0; }
.matching-note { max-width: 900px; margin: 21px 0 0; color: #6b786f; font-size: 12px; }
.intro-page .task-meter strong { font-size: 17px; }
.algorithm-hint { margin: 22px 0 0; color: #64766a; font-size: 11px; }
.intro-page .feature-tabs, .intro-page .feature-demo { scroll-margin-top: 95px; }
@media (max-width: 1100px) {
  .intro-page .desktop-nav { gap: 20px; }
  .hero-layout { gap: 38px; }
  .feature-panel { gap: 40px; padding: 36px; }
  .feature-copy h3 { font-size: 30px; }
}
@media (max-width: 960px) {
  .hero-layout { grid-template-columns: 1fr; gap: 48px; max-width: 650px; }
  .intro-page .hero { padding-top: 128px; }
  .intro-page .hero-inner { max-width: 560px; }
  .study-preview { max-width: 540px; width: 100%; justify-self: center; transform: none; }
  .intro-page .module-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .intro-page .module-grid article, .intro-page .module-grid .module-feature, .intro-page .module-grid article:nth-child(n+2) { grid-column: auto; }
  .intro-page .module-grid article:last-child { grid-column: 1 / -1; }
  .feature-panel { gap: 32px; padding: 32px 24px; }
  .feature-copy h3 { font-size: 28px; }
  .feature-demo { padding: 18px; }
  .feature-tabs button { gap: 8px; }
  .feature-tabs button span { font-size: 15px; }
  .support-grid { gap: 24px; }
  .support-grid h3 { font-size: 20px; }
}
@media (max-width: 640px) {
  .intro-page section[id] { scroll-margin-top: 80px; }
  .intro-page .hero { padding-top: 112px; }
  .hero-layout { gap: 40px; padding-bottom: 40px; }
  .intro-page .hero h1 { font-size: 78px; }
  .intro-page .hero-lead { max-width: none; margin: 24px 0 16px; font-size: clamp(22px, 6.1vw, 29px); }
  .intro-page .hero-copy { font-size: 14px; }
  .intro-page .hero-actions { flex-direction: row; gap: 8px; }
  .intro-page .hero-actions .button { flex: 1; gap: 8px; padding: 0 10px; font-size: 12px; }
  .hero-tags { gap: 18px; margin-top: 22px; font-size: 11px; }
  .preview-caption { padding: 14px 18px; }
  .study-preview-body { padding: 22px 18px 18px; }
  .study-preview h2 { font-size: 22px; }
  .preview-character-grid { gap: 6px; }
  .preview-character-grid > span { font-size: 28px; }
  .intro-page .problem-band, .intro-page .algorithm-section, .intro-page .modules-section, .intro-page .app-section, .intro-page .workflow-section, .matching-section { padding: 68px 0; }
  .intro-page .section-heading h2 { font-size: 32px; }
  .intro-page .centered-heading { margin-bottom: 34px; text-align: left; }
  .intro-page .app-section .eyebrow { justify-content: flex-start; }
  .intro-page .module-grid { grid-template-columns: minmax(0, 1fr); margin-top: 36px; }
  .intro-page .module-grid article, .intro-page .module-grid article:last-child { grid-column: auto; min-height: 240px; }
  .feature-tabs button { min-height: 68px; flex-direction: column; gap: 3px; font-size: 9px; }
  .feature-tabs button span { font-size: 12px; }
  .feature-panel { grid-template-columns: minmax(0, 1fr); gap: 28px; min-height: auto; padding: 28px 18px; }
  .feature-copy h3 { font-size: 28px; }
  .feature-copy > p { font-size: 13px; }
  .feature-copy li { font-size: 12px; }
  .feature-demo { padding: 18px 14px; }
  .demo-title strong { font-size: 12px; }
  .demo-title > span { font-size: 9px; }
  .demo-calendar { gap: 6px; }
  .demo-calendar > span { padding: 10px 0; font-size: 18px; }
  .demo-note { line-height: 1.8; }
  .support-grid { grid-template-columns: 1fr; gap: 26px; margin-top: 36px; }
  .support-grid h3 { margin-top: 12px; }
  .matching-table th, .matching-table td { padding: 18px 10px; font-size: 11px; white-space: nowrap; }
  .matching-table small { font-size: 9px; }
  .intro-page .closing-inner h2 { font-size: 34px; line-height: 1.4; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { transition-duration: 0.01ms !important; animation-duration: 0.01ms !important; animation-iteration-count: 1 !important; }
}