/* =========================================================
   有墨 AI · YAUMO — 静态官网样式
   设计语言：墨黑 / 近白冷底 / 朱砂红（点缀）/ 落款金（premium）
   字体：衬线标题 + 系统无衬线正文（无外部资源引用）
   ========================================================= */

:root {
  --background: #fbfbfd;
  --surface: #ffffff;
  --ink: #1d1d1f;
  --ink-soft: #424245;
  --ink-muted: #6e6e73;
  --ink-faint: #a1a1a6;
  --line: #e6e6e8;
  --line-soft: #f0f0f2;
  --line-strong: #d2d2d7;
  --brand: #c0392b;
  --brand-hover: #a93226;
  --brand-soft: #fbeae7;
  --gold: #9a7a2e;
  --gold-hover: #856a27;
  --gold-soft: #f3ecd8;
  --success: #2f9e44;
  --font-sans: system-ui, -apple-system, "PingFang SC", "Microsoft YaHei", "Segoe UI", Roboto, sans-serif;
  --font-serif: "Noto Serif SC", "Songti SC", "STSong", "SimSun", serif;
  --maxw: 1240px;
  --radius: 18px;
  --radius-sm: 12px;
  --shadow-sm: 0 1px 2px rgba(0,0,0,.04), 0 4px 16px rgba(0,0,0,.04);
  --shadow-md: 0 8px 30px rgba(20,20,30,.08), 0 2px 8px rgba(20,20,30,.04);
  --shadow-lg: 0 24px 60px rgba(20,20,30,.14);
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  background: var(--background);
  color: var(--ink);
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

a { color: inherit; text-decoration: none; }

.container {
  width: 100%;
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 0 24px;
}

/* ── 顶部导航 ── */
.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(251,251,253,.72);
  backdrop-filter: saturate(180%) blur(14px);
  -webkit-backdrop-filter: saturate(180%) blur(14px);
  border-bottom: 1px solid transparent;
  transition: border-color .3s ease, box-shadow .3s ease;
}
.site-header.scrolled {
  border-bottom-color: var(--line);
  box-shadow: 0 1px 0 rgba(0,0,0,.02);
}
.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 66px;
}
.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-weight: 700;
}
.brand-mark {
  display: grid;
  place-items: center;
  width: 30px;
  height: 30px;
  border-radius: 9px;
  background: var(--brand);
  color: #fff;
  font-family: var(--font-serif);
  font-size: 17px;
  font-weight: 700;
  box-shadow: var(--shadow-sm);
}
.brand-text {
  font-family: var(--font-serif);
  font-size: 19px;
  letter-spacing: .02em;
  color: var(--ink);
}
.brand-text em { color: var(--brand); font-style: normal; margin: 0 1px; }

.nav { display: flex; gap: 30px; }
.nav a {
  position: relative;
  font-size: 14.5px;
  color: var(--ink-muted);
  transition: color .2s ease;
}
.nav a::after {
  content: "";
  position: absolute;
  left: 0; bottom: -6px;
  width: 0; height: 2px;
  background: var(--brand);
  transition: width .25s ease;
}
.nav a:hover { color: var(--ink); }
.nav a:hover::after { width: 100%; }

.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  width: 40px; height: 40px;
  border: none; background: transparent;
  cursor: pointer; align-items: center; justify-content: center;
}
.nav-toggle span {
  width: 22px; height: 2px; border-radius: 2px;
  background: var(--ink);
  transition: transform .25s ease, opacity .25s ease;
}
.nav-toggle[aria-expanded="true"] span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.nav-toggle[aria-expanded="true"] span:nth-child(2) { opacity: 0; }
.nav-toggle[aria-expanded="true"] span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

.mobile-nav {
  display: none;
  flex-direction: column;
  padding: 8px 24px 18px;
  border-top: 1px solid var(--line-soft);
  background: var(--background);
}
.mobile-nav a {
  padding: 12px 0;
  font-size: 15px;
  color: var(--ink-soft);
  border-bottom: 1px solid var(--line-soft);
}
.mobile-nav a:last-child { border-bottom: none; }

/* ── Hero ── */
.hero {
  position: relative;
  overflow: hidden;
  padding: 72px 0 90px;
}
.ambient-glow {
  position: absolute;
  left: 50%; top: -22%;
  width: 80rem; height: 44rem;
  transform: translateX(-50%);
  background:
    radial-gradient(40% 40% at 30% 30%, rgba(192,57,43,.10), transparent 70%),
    radial-gradient(36% 36% at 72% 40%, rgba(154,122,46,.10), transparent 70%);
  filter: blur(20px);
  pointer-events: none;
}
.hero-grid {
  position: relative;
  display: grid;
  grid-template-columns: 1.05fr .95fr;
  align-items: center;
  gap: 56px;
}
.eyebrow {
  font-size: 12px;
  font-weight: 700;
  letter-spacing: .22em;
  text-transform: uppercase;
  color: var(--brand);
}
.hero-title {
  margin: 16px 0 0;
  font-family: var(--font-serif);
  font-weight: 900;
  font-size: clamp(2.6rem, 6vw, 3.75rem);
  line-height: 1.14;
  letter-spacing: -.01em;
  color: var(--ink);
}
.hero-title .accent { color: var(--brand); }
.caret {
  display: inline-block;
  width: 3px; height: .92em;
  margin-left: 4px;
  background: var(--brand);
  vertical-align: -0.12em;
  animation: blink 1.05s step-end infinite;
}
.hero-lead {
  margin: 22px 0 0;
  max-width: 32em;
  font-size: 17.5px;
  line-height: 1.95;
  color: var(--ink-soft);
}
.hero-actions { margin-top: 30px; }
.link-quiet {
  font-size: 15px;
  color: var(--ink-muted);
  border-bottom: 1px solid var(--line-strong);
  padding-bottom: 2px;
  transition: color .2s ease, border-color .2s ease;
}
.link-quiet:hover { color: var(--ink); border-color: var(--ink); }

.stats {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 16px;
  max-width: 520px;
  margin: 46px 0 0;
}
.stat-num {
  font-family: var(--font-serif);
  font-size: 2rem;
  font-weight: 900;
  line-height: 1;
  color: var(--ink);
}
.stat-label {
  margin: 7px 0 0;
  font-size: 12.5px;
  color: var(--ink-muted);
}

/* ── Hero Mockup ── */
.hero-visual { position: relative; }
.mockup {
  position: relative;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  box-shadow: var(--shadow-lg);
  overflow: hidden;
}
.mockup-bar {
  display: flex;
  align-items: center;
  gap: 7px;
  padding: 13px 16px;
  border-bottom: 1px solid var(--line-soft);
  background: #fcfcfd;
}
.mockup-bar .dot {
  width: 11px; height: 11px; border-radius: 50%;
  background: var(--line-strong);
}
.mockup-bar .dot:nth-child(1) { background: #f0c0bb; }
.mockup-bar .dot:nth-child(2) { background: #f3e6c2; }
.mockup-bar .dot:nth-child(3) { background: #cfe6d4; }
.mockup-title {
  margin-left: 8px;
  font-size: 12.5px;
  color: var(--ink-muted);
  letter-spacing: .04em;
}
.mockup-body { padding: 22px 22px 26px; }
.mockup-book-title {
  font-family: var(--font-serif);
  font-size: 22px;
  font-weight: 700;
  color: var(--ink);
}
.mockup-genre {
  margin-top: 4px;
  font-size: 12.5px;
  color: var(--brand);
  font-weight: 600;
}
.mockup-outline {
  margin: 18px 0 0;
  padding: 0;
  list-style: none;
  font-size: 13.5px;
  line-height: 1.9;
  color: var(--ink-soft);
}
.mockup-outline li { padding: 1px 0; }
.mockup-outline b { color: var(--ink); font-weight: 700; }
.mockup-outline .indent { padding-left: 14px; color: var(--ink-muted); }
.mockup-outline .typing { color: var(--brand); }
.typing-caret {
  display: inline-block;
  width: 2px; height: 1em;
  margin-left: 2px;
  background: var(--brand);
  vertical-align: -2px;
  animation: blink 1.05s step-end infinite;
}
.agent-chip {
  position: absolute;
  right: 16px; top: 64px;
  display: inline-flex;
  align-items: center;
  gap: 7px;
  padding: 7px 13px;
  background: var(--brand);
  color: #fff;
  font-size: 12.5px;
  font-weight: 600;
  border-radius: 999px;
  box-shadow: var(--shadow-md);
}
.agent-spark { animation: pulse 1.8s ease-in-out infinite; }

.float-card {
  position: absolute;
  display: flex;
  flex-direction: column;
  gap: 2px;
  padding: 12px 15px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
  box-shadow: var(--shadow-md);
  animation: floaty 5s ease-in-out infinite;
}
.float-card .fc-k { font-size: 12px; color: var(--ink-muted); }
.float-card .fc-v { font-size: 14px; font-weight: 700; color: var(--ink); }
.float-card--a { left: -22px; bottom: 26px; }
.float-card--b { right: -18px; bottom: 92px; animation-delay: 1.4s; }
.float-card--b .fc-v { color: var(--success); }

/* ── 通用 section ── */
.section { padding: 96px 0; border-top: 1px solid var(--line-soft); }
.section--alt { background: #f6f6f8; }
.section-head { max-width: 42em; margin-bottom: 52px; }
.section-head.center { margin-left: auto; margin-right: auto; text-align: center; }
.section-title {
  margin: 0;
  font-family: var(--font-serif);
  font-size: clamp(1.9rem, 4vw, 2.375rem);
  font-weight: 700;
  line-height: 1.25;
  letter-spacing: -.01em;
  color: var(--ink);
}
.section-title .accent { color: var(--brand); }
.section-sub {
  margin: 14px 0 0;
  font-size: 15px;
  color: var(--ink-muted);
}

/* ── 功能亮点 ── */
.feature-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 22px;
}
.feature-card {
  padding: 30px 28px 32px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  transition: transform .25s ease, box-shadow .25s ease, border-color .25s ease;
}
.feature-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-md);
  border-color: var(--line-strong);
}
.feature-num {
  font-family: var(--font-serif);
  font-size: 17px;
  letter-spacing: .1em;
  color: var(--brand);
}
.feature-title {
  margin: 14px 0 10px;
  font-family: var(--font-serif);
  font-size: 19px;
  font-weight: 700;
  color: var(--ink);
}
.feature-desc {
  margin: 0;
  font-size: 14px;
  line-height: 1.85;
  color: var(--ink-muted);
}

/* ── 双模式 ── */
.mode-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 0;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
  background: var(--surface);
}
.mode-card { padding: 40px; }
.mode-card + .mode-card { border-left: 1px solid var(--line); }
.mode-name {
  font-family: var(--font-serif);
  font-size: 23px;
  font-weight: 700;
  color: var(--ink);
}
.mode-tag {
  display: inline-block;
  margin-top: 8px;
  font-size: 12.5px;
  font-weight: 600;
  padding: 4px 11px;
  border-radius: 999px;
}
.tag-brand { background: var(--brand-soft); color: var(--brand); }
.tag-gold { background: var(--gold-soft); color: var(--gold); }
.mode-desc {
  margin: 18px 0 0;
  font-size: 14px;
  line-height: 1.9;
  color: var(--ink-muted);
}
.mode-list {
  margin: 20px 0 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: 10px;
}
.mode-list li {
  position: relative;
  padding-left: 20px;
  font-size: 14px;
  color: var(--ink-soft);
}
.mode-list li::before {
  content: "—";
  position: absolute;
  left: 0;
  color: var(--brand);
}

/* ── 守护模式 ── */
.guardian-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 56px;
  align-items: center;
}
.guardian-sub { max-width: 25em; }
.pipeline {
  margin: 0;
  padding: 0;
  list-style: none;
  border-top: 1px solid var(--line);
}
.pipeline li {
  display: flex;
  align-items: center;
  gap: 18px;
  padding: 13px 4px;
  border-bottom: 1px solid var(--line-soft);
}
.step-no {
  width: 30px;
  font-family: var(--font-serif);
  font-size: 13px;
  letter-spacing: .05em;
  color: var(--ink-faint);
}
.step-name { font-size: 14.5px; color: var(--ink-soft); }
.pipeline .step-final { border-bottom: none; }
.pipeline .step-final .step-name { color: var(--ink); font-weight: 700; }
.step-done {
  margin-left: auto;
  font-size: 12.5px;
  font-weight: 600;
  color: var(--success);
}

/* ── 题材 ── */
.genre-grid {
  display: grid;
  grid-template-columns: repeat(6, 1fr);
  gap: 16px;
}
.genre-card {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 12px;
  padding: 28px 12px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  transition: transform .2s ease, border-color .2s ease, box-shadow .2s ease;
}
.genre-card:hover {
  transform: translateY(-3px);
  border-color: var(--brand);
  box-shadow: var(--shadow-sm);
}
.genre-emoji { font-size: 26px; }
.genre-name {
  font-family: var(--font-serif);
  font-size: 15px;
  font-weight: 700;
  color: var(--ink);
}

/* ── 创作者说 ── */
.voice-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 0;
  border-top: 1px solid var(--line);
}
.voice-card {
  margin: 0;
  padding: 34px 36px;
}
.voice-card + .voice-card { border-left: 1px solid var(--line-soft); }
.voice-quote {
  font-family: var(--font-serif);
  font-size: 30px;
  line-height: 1;
  color: var(--brand);
}
.voice-text {
  margin: 16px 0 0;
  font-size: 14.5px;
  line-height: 1.9;
  color: var(--ink-soft);
}
.voice-author {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-top: 22px;
}
.voice-avatar {
  display: grid;
  place-items: center;
  width: 38px; height: 38px;
  border-radius: 50%;
  border: 1px solid var(--line);
  font-family: var(--font-serif);
  font-weight: 700;
  color: var(--brand);
}
.voice-meta { display: flex; flex-direction: column; }
.voice-meta b { font-size: 14px; color: var(--ink); }
.voice-meta i { font-style: normal; font-size: 12.5px; color: var(--ink-muted); }

/* ── 品牌收尾 ── */
.closing {
  padding: 110px 0;
  background:
    radial-gradient(50% 60% at 50% 0%, rgba(192,57,43,.06), transparent 70%),
    var(--background);
  border-top: 1px solid var(--line-soft);
  text-align: center;
}
.closing-inner { max-width: 720px; margin: 0 auto; }
.center-eyebrow { text-align: center; }
.closing-title {
  margin: 16px 0 0;
  font-family: var(--font-serif);
  font-size: clamp(2rem, 4.5vw, 2.75rem);
  font-weight: 900;
  line-height: 1.18;
  letter-spacing: -.01em;
  color: var(--ink);
}
.closing-sub {
  margin: 20px 0 0;
  font-size: 15px;
  color: var(--ink-muted);
}

/* ── 页脚 ── */
.site-footer {
  background: #15151a;
  color: #c7c7cc;
  padding: 54px 0 34px;
}
.footer-inner {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  flex-wrap: wrap;
  gap: 28px;
  padding-bottom: 30px;
  border-bottom: 1px solid rgba(255,255,255,.08);
}
.footer-brand { display: flex; align-items: center; gap: 12px; }
.footer-brand .brand-mark { background: var(--brand); }
.footer-brand-name {
  font-family: var(--font-serif);
  font-size: 18px;
  font-weight: 700;
  color: #fff;
}
.footer-brand-desc { font-size: 12.5px; color: #8e8e93; margin-top: 3px; }
.footer-nav { display: flex; flex-wrap: wrap; gap: 22px; }
.footer-nav a { font-size: 14px; color: #a1a1a6; transition: color .2s ease; }
.footer-nav a:hover { color: #fff; }
.footer-legal {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 22px;
  align-items: center;
  padding-top: 22px;
  margin: 0 auto;
  font-size: 12.5px;
  color: #8e8e93;
}
.footer-legal p { margin: 0; }
.beian-link {
  color: #c7c7cc;
  border-bottom: 1px dashed rgba(255,255,255,.25);
  transition: color .2s ease, border-color .2s ease;
}
.beian-link:hover { color: #fff; border-color: #fff; }

/* ── 滚动渐显 ── */
.reveal {
  opacity: 0;
  transform: translateY(22px);
  transition: opacity .7s cubic-bezier(.2,.7,.2,1), transform .7s cubic-bezier(.2,.7,.2,1);
  will-change: opacity, transform;
}
.reveal.is-visible { opacity: 1; transform: none; }

/* ── 动画 ── */
@keyframes blink { 0%, 100% { opacity: 1; } 50% { opacity: 0; } }
@keyframes pulse { 0%, 100% { opacity: 1; transform: scale(1); } 50% { opacity: .55; transform: scale(.86); } }
@keyframes floaty { 0%, 100% { transform: translateY(0); } 50% { transform: translateY(-9px); } }

/* ── 响应式 ── */
@media (max-width: 980px) {
  .hero-grid { grid-template-columns: 1fr; gap: 48px; }
  .hero-visual { max-width: 520px; }
  .feature-grid { grid-template-columns: repeat(2, 1fr); }
  .guardian-grid { grid-template-columns: 1fr; gap: 36px; }
  .genre-grid { grid-template-columns: repeat(3, 1fr); }
  .voice-grid { grid-template-columns: 1fr; }
  .voice-card + .voice-card { border-left: none; border-top: 1px solid var(--line-soft); }
}
@media (max-width: 680px) {
  .nav { display: none; }
  .nav-toggle { display: flex; }
  .mobile-nav.show { display: flex; }
  .section { padding: 68px 0; }
  .stats { grid-template-columns: repeat(2, 1fr); gap: 22px 16px; }
  .feature-grid { grid-template-columns: 1fr; }
  .mode-grid { grid-template-columns: 1fr; }
  .mode-card + .mode-card { border-left: none; border-top: 1px solid var(--line); }
  .genre-grid { grid-template-columns: repeat(2, 1fr); }
  .float-card { display: none; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .reveal { opacity: 1; transform: none; transition: none; }
  .caret, .typing-caret, .agent-spark, .float-card { animation: none; }
}