:root {
  --ink: #101010;
  --paper: #f4f2ed;
  --white: #fff;
  --muted: #77736c;
  --line: #d8d3ca;
  --dark-line: #3d3b37;
  --gold: #c6a873;
  --soft: #e8e3da;
  --danger: #7d3f3f;
}

* { box-sizing: border-box; }

html { background: var(--paper); color: var(--ink); }

body {
  margin: 0;
  min-width: 320px;
  background: var(--paper);
  font-family: -apple-system, BlinkMacSystemFont, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  line-height: 1.65;
  letter-spacing: 0;
}

button { font: inherit; }

.site-shell { width: 100%; overflow: hidden; }

.product-hero,
.method-band,
.test-panel {
  background: var(--ink);
  color: var(--white);
}

.product-hero { min-height: 760px; padding: 72px max(24px, calc((100% - 1060px) / 2)) 86px; display: flex; flex-direction: column; justify-content: center; }
.eyebrow, .section-label { color: var(--gold); font-size: 12px; font-weight: 800; letter-spacing: 0.08em; text-transform: uppercase; }

h1, h2, h3, p { margin: 0; }

.product-hero h1 { max-width: 920px; margin-top: 32px; font-family: "Songti SC", "STSong", serif; font-size: clamp(46px, 8vw, 88px); line-height: 1.12; font-weight: 600; }
.product-hero h1 em { color: #c7c2b8; font-style: normal; }
.hero-copy { max-width: 670px; margin-top: 34px; color: #d6d2ca; font-size: 19px; line-height: 1.8; }
.hero-pain-grid { display: grid; grid-template-columns: repeat(2, minmax(0, 300px)); gap: 24px; margin-top: 34px; }
.hero-pain-grid div { padding-top: 15px; border-top: 1px solid #46423b; }
.hero-pain-grid b { display: block; color: var(--gold); font-size: 13px; }
.hero-pain-grid span { display: block; margin-top: 8px; color: #bdb8ae; font-size: 14px; line-height: 1.7; }
.hero-actions { display: flex; align-items: center; gap: 18px; margin-top: 52px; color: #a9a49a; font-size: 13px; }
.qualification-entry { display: grid; gap: 6px; min-width: min(360px, 100%); }
.qualification-entry label { color: var(--gold); font-size: 12px; font-weight: 800; }
.qualification-entry input { width: 100%; min-height: 46px; padding: 0 13px; border: 1px solid #5b554b; border-radius: 4px; background: #171717; color: #fff; outline: none; text-transform: uppercase; }
.qualification-entry input:focus { border-color: var(--gold); }
.qualification-entry small { color: #9e988e; font-size: 11px; line-height: 1.5; }

.primary-btn, .secondary-btn {
  min-height: 50px;
  padding: 0 22px;
  border: 1px solid transparent;
  border-radius: 4px;
  cursor: pointer;
  font-weight: 800;
}

.primary-btn { background: var(--gold); color: var(--ink); }
.primary-btn:hover { background: #d3ba8c; }
.primary-btn:disabled { cursor: wait; opacity: .55; }
.secondary-btn { border-color: var(--dark-line); background: transparent; color: var(--white); }
.secondary-btn:hover { border-color: var(--gold); color: var(--gold); }

.statement-band, .rule-band, .chapter-band, .boundary-band { padding: 96px max(24px, calc((100% - 1060px) / 2)); }
.statement-band { background: var(--white); }
.statement-band h2, .chapter-band h2, .boundary-band h2 { max-width: 820px; margin-top: 28px; font-family: "Songti SC", "STSong", serif; font-size: clamp(34px, 5vw, 58px); line-height: 1.25; font-weight: 600; }
.statement-band p { max-width: 720px; margin-top: 28px; color: #4d4a45; font-size: 18px; line-height: 1.9; }
.statement-grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 42px; max-width: 900px; margin-top: 48px; }
.statement-grid article { padding-top: 18px; border-top: 1px solid var(--line); }
.statement-grid b { font-size: 18px; }
.statement-grid p { max-width: none; margin-top: 14px; font-size: 16px; }
.strong-line { color: var(--ink) !important; font-size: 24px !important; font-weight: 800; }

.rule-band { background: var(--paper); }
.rule-grid { display: grid; grid-template-columns: repeat(3, 1fr); margin-top: 46px; border-top: 1px solid var(--line); }
.rule-grid article { min-height: 280px; padding: 26px 24px 20px 0; border-right: 1px solid var(--line); }
.rule-grid article:not(:first-child) { padding-left: 24px; }
.rule-grid article:last-child { border-right: 0; }
.rule-grid span { color: var(--muted); font-size: 12px; font-weight: 800; }
.rule-grid h3 { margin-top: 55px; font-size: 28px; line-height: 1.25; }
.rule-grid p { margin-top: 18px; color: var(--muted); font-size: 15px; line-height: 1.75; }

.method-band { padding: 96px max(24px, calc((100% - 1060px) / 2)); }
.method-layout { display: grid; grid-template-columns: 1.1fr .9fr; gap: 72px; margin-top: 42px; align-items: end; }
.method-layout h2 { font-family: "Songti SC", "STSong", serif; font-size: clamp(34px, 5vw, 58px); line-height: 1.28; font-weight: 600; }
.method-layout p { max-width: 570px; margin-top: 28px; color: #bcb7ae; font-size: 17px; line-height: 1.85; }
.deliver-list { border-top: 1px solid var(--dark-line); }
.deliver-list div { display: flex; align-items: baseline; gap: 18px; padding: 20px 0; border-bottom: 1px solid var(--dark-line); }
.deliver-list b { min-width: 64px; color: var(--gold); font-family: "Songti SC", serif; font-size: 30px; font-weight: 600; }
.deliver-list span { color: #d2cec6; font-size: 16px; }

.chapter-band { background: var(--white); }
.chapter-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 0 38px; margin-top: 48px; border-top: 1px solid var(--line); }
.chapter-grid div { min-height: 150px; padding: 24px 0; border-bottom: 1px solid var(--line); }
.chapter-grid strong { display: inline-block; font-size: 22px; }
.chapter-grid span { float: right; color: var(--muted); font-size: 12px; }
.chapter-grid p { max-width: 390px; margin-top: 14px; color: var(--muted); font-size: 14px; line-height: 1.7; }

.boundary-band { background: #e9e5dd; }
.boundary-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 28px; margin-top: 48px; }
.boundary-grid p { padding-top: 20px; border-top: 1px solid #bdb7ab; color: #4d4941; font-size: 15px; line-height: 1.8; }

.test-panel { padding: 76px max(24px, calc((100% - 920px) / 2)) 88px; }
.test-header { display: flex; justify-content: space-between; align-items: flex-end; gap: 24px; }
.test-header h2 { margin-top: 18px; font-family: "Songti SC", "STSong", serif; font-size: clamp(30px, 5vw, 52px); line-height: 1.25; font-weight: 600; }
.test-header > strong { color: var(--gold); font-size: 18px; white-space: nowrap; }
.progress-track { height: 4px; margin-top: 30px; background: var(--dark-line); }
.progress-track span { display: block; width: 4%; height: 100%; background: var(--gold); transition: width .2s ease; }
.test-note { margin-top: 14px; color: #aaa49a; font-size: 13px; }
#questionHost { margin-top: 44px; }
.question-card { padding: 34px; border: 1px solid var(--dark-line); background: #171717; }
.question-index { color: var(--gold); font-size: 12px; font-weight: 800; }
.question-card h3 { margin-top: 18px; font-family: "Songti SC", "STSong", serif; font-size: clamp(28px, 4vw, 44px); line-height: 1.35; font-weight: 600; }
.question-card p { margin-top: 12px; color: #aaa59c; font-size: 14px; }
.option-list { display: grid; gap: 10px; margin-top: 32px; }
.option { position: relative; }
.option input { position: absolute; opacity: 0; pointer-events: none; }
.option label { display: grid; grid-template-columns: 34px 1fr; gap: 14px; align-items: start; padding: 17px 16px; border: 1px solid var(--dark-line); color: #e7e3dc; cursor: pointer; font-size: 15px; line-height: 1.7; }
.option label span { display: grid; place-items: center; width: 28px; height: 28px; border: 1px solid #625e55; border-radius: 50%; color: #aaa59c; font-size: 12px; font-weight: 800; }
.option input:checked + label { border-color: var(--gold); background: #25221c; color: var(--white); }
.option input:checked + label span { border-color: var(--gold); color: var(--gold); }
.question-actions { display: flex; justify-content: space-between; gap: 14px; margin-top: 26px; }

.site-footer { display: flex; justify-content: space-between; gap: 16px; padding: 24px max(24px, calc((100% - 1060px) / 2)); color: var(--muted); font-size: 12px; }
.hidden { display: none !important; }

@media (max-width: 720px) {
  .product-hero { min-height: 680px; padding-top: 44px; padding-bottom: 56px; }
  .hero-pain-grid, .statement-grid { grid-template-columns: 1fr; gap: 22px; }
  .hero-actions { align-items: stretch; flex-direction: column; gap: 12px; }
  .rule-grid, .method-layout, .boundary-grid { grid-template-columns: 1fr; gap: 0; }
  .rule-grid article, .rule-grid article:not(:first-child) { min-height: auto; padding: 24px 0; border-right: 0; border-bottom: 1px solid var(--line); }
  .rule-grid article:last-child { border-bottom: 0; }
  .rule-grid h3 { margin-top: 24px; }
  .method-layout { gap: 44px; }
  .chapter-grid { grid-template-columns: 1fr; }
  .chapter-grid div { min-height: 0; }
  .test-header { align-items: flex-start; flex-direction: column; }
  .question-card { padding: 24px 18px; }
  .question-actions { flex-wrap: wrap; }
  .question-actions .primary-btn { flex: 1 0 100%; order: -1; }
  .site-footer { flex-direction: column; }
}