/* ========================================
   知余 官网 - 基础样式
   ======================================== */

:root {
  --color-bg: #faf8f5;
  --color-surface: #ffffff;
  --color-surface-alt: #f5f1ec;
  --color-ink: #1a1a1a;
  --color-ink-secondary: #666660;
  --color-ink-muted: #999990;
  --color-accent: #2d5016;
  --color-accent-light: #e8f0e0;
  --color-accent-hover: #3d6a20;
  --color-cash: #2d5016;
  --color-credit: #c05621;
  --color-warn: #d4503a;
  --color-good: #2d5016;
  --color-border: #e8e4de;
  --color-border-light: #f0ebe3;
  --font-serif: 'Noto Serif SC', 'Songti SC', serif;
  --font-sans: 'Noto Sans SC', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 20px;
  --radius-xl: 24px;
  --shadow-sm: 0 1px 3px rgba(0,0,0,0.06);
  --shadow-md: 0 4px 16px rgba(0,0,0,0.08);
  --shadow-lg: 0 8px 32px rgba(0,0,0,0.1);
  --shadow-xl: 0 16px 48px rgba(0,0,0,0.12);
  --container-max: 1200px;
  --transition: 0.2s ease;
}

*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
  scroll-padding-top: 80px;
}

body {
  font-family: var(--font-sans);
  color: var(--color-ink);
  background: var(--color-bg);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}

a { color: inherit; text-decoration: none; }
img { max-width: 100%; height: auto; }

/* ========================================
   Navigation
   ======================================== */

.navbar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  background: rgba(250, 248, 245, 0.85);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--color-border-light);
  height: 64px;
}

.nav-container {
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 24px;
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.nav-logo {
  display: flex;
  align-items: center;
  gap: 10px;
}

.logo-icon {
  display: block;
  width: 36px;
  height: 36px;
  object-fit: cover;
  border-radius: 9px;
  box-shadow: 0 6px 14px rgba(31, 51, 34, 0.16);
}

.logo-text {
  font-family: var(--font-serif);
  font-weight: 700;
  font-size: 20px;
  letter-spacing: 0.02em;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 32px;
}

.nav-links a {
  font-size: 14px;
  font-weight: 500;
  color: var(--color-ink-secondary);
  transition: color var(--transition);
}

.nav-links a:hover { color: var(--color-ink); }

.nav-docs-btn {
  background: var(--color-ink);
  color: #fff !important;
  padding: 8px 20px;
  border-radius: var(--radius-sm);
  font-size: 13px !important;
  transition: background var(--transition) !important;
}

.nav-docs-btn:hover { background: #333 !important; }

.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 4px;
}

.nav-toggle span {
  display: block;
  width: 22px;
  height: 2px;
  background: var(--color-ink);
  border-radius: 1px;
}

/* ========================================
   Hero
   ======================================== */

.hero {
  padding: 140px 0 80px;
  overflow: hidden;
}

.hero-container {
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 24px;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 60px;
  align-items: center;
}

.hero-title {
  font-family: var(--font-serif);
  font-size: 52px;
  font-weight: 700;
  line-height: 1.2;
  letter-spacing: -0.02em;
}

.hero-title-line { display: block; }
.hero-title-line.accent { color: var(--color-accent); }

.hero-subtitle {
  margin-top: 24px;
  font-size: 17px;
  color: var(--color-ink-secondary);
  line-height: 1.8;
  max-width: 480px;
}

.hero-actions {
  margin-top: 36px;
  display: flex;
  gap: 16px;
}

.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 12px 28px;
  border-radius: var(--radius-sm);
  font-size: 15px;
  font-weight: 600;
  transition: all var(--transition);
  cursor: pointer;
  border: none;
}

.btn-primary {
  background: var(--color-ink);
  color: #fff;
}
.btn-primary:hover { background: #333; transform: translateY(-1px); }

.btn-secondary {
  background: var(--color-surface);
  color: var(--color-ink);
  border: 1px solid var(--color-border);
}
.btn-secondary:hover { border-color: var(--color-ink-muted); }

.btn-lg {
  padding: 16px 36px;
  font-size: 16px;
  border-radius: var(--radius-md);
}

.hero-stats {
  margin-top: 48px;
  display: flex;
  align-items: center;
  gap: 24px;
}

.stat { text-align: center; }

.stat-number {
  display: block;
  font-family: var(--font-serif);
  font-size: 24px;
  font-weight: 700;
  color: var(--color-accent);
}

.stat-label {
  display: block;
  font-size: 12px;
  color: var(--color-ink-muted);
  margin-top: 4px;
}

.stat-divider {
  width: 1px;
  height: 32px;
  background: var(--color-border);
}

/* Phone Mockup */
.hero-visual {
  display: flex;
  justify-content: center;
}

.phone-mockup {
  width: 280px;
  background: var(--color-ink);
  border-radius: 36px;
  padding: 12px;
  box-shadow: var(--shadow-xl);
}

.phone-mockup-small {
  width: 220px;
}

.phone-mockup-yuli {
  width: 300px;
  margin: 0 auto;
}

.phone-screen {
  background: var(--color-bg);
  border-radius: 26px;
  overflow: hidden;
  aspect-ratio: 1206 / 2622;
}

.app-screenshot {
  display: block;
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: top center;
}

/* ========================================
   Sections
   ======================================== */

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

.section-header {
  text-align: center;
  margin-bottom: 56px;
}

.section-header h2 {
  font-family: var(--font-serif);
  font-size: 32px;
  font-weight: 700;
}

.section-header p {
  color: var(--color-ink-secondary);
  margin-top: 12px;
  font-size: 16px;
}

.section-tag {
  display: inline-block;
  font-size: 12px;
  font-weight: 600;
  color: var(--color-accent);
  background: var(--color-accent-light);
  padding: 4px 12px;
  border-radius: 4px;
  margin-bottom: 16px;
  letter-spacing: 0.05em;
}

/* ========================================
   Features Grid
   ======================================== */

.features {
  padding: 100px 0;
}

.features-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.feature-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border-light);
  border-radius: var(--radius-lg);
  padding: 32px;
  transition: all 0.3s ease;
}

.feature-card:hover {
  border-color: var(--color-border);
  box-shadow: var(--shadow-md);
  transform: translateY(-4px);
}

.feature-icon {
  width: 48px;
  height: 48px;
  background: var(--color-surface-alt);
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 20px;
}

.feature-icon svg {
  width: 24px;
  height: 24px;
  color: var(--color-accent);
}

.feature-card h3 {
  font-size: 18px;
  font-weight: 600;
  margin-bottom: 8px;
}

.feature-card p {
  font-size: 14px;
  color: var(--color-ink-secondary);
  line-height: 1.7;
}

/* ========================================
   Product Screens
   ======================================== */

.product-screens {
  padding: 100px 0;
  background: var(--color-surface);
}

.screen-gallery {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 28px;
  align-items: stretch;
}

.screen-shot-card {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: space-between;
  gap: 18px;
  min-height: 452px;
  padding: 28px 20px 24px;
  background: var(--color-bg);
  border: 1px solid var(--color-border-light);
  border-radius: var(--radius-lg);
}

.screen-shot-card .phone-mockup-small {
  flex: 0 0 auto;
}

.screen-shot-card figcaption {
  font-family: var(--font-serif);
  font-size: 17px;
  font-weight: 600;
  color: var(--color-ink);
}

/* ========================================
   Yuli Section
   ======================================== */

.yuli-section {
  padding: 100px 0;
  background: var(--color-surface);
}

.yuli-layout {
  display: grid;
  grid-template-columns: 1fr 380px;
  gap: 80px;
  align-items: center;
}

.yuli-content h2 {
  font-family: var(--font-serif);
  font-size: 32px;
  font-weight: 700;
}

.yuli-desc {
  margin-top: 16px;
  color: var(--color-ink-secondary);
  font-size: 15px;
  line-height: 1.8;
}

.yuli-dimensions {
  margin-top: 32px;
  display: flex;
  flex-direction: column;
  gap: 20px;
}

.dimension-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 6px;
}

.dimension-name {
  font-size: 14px;
  font-weight: 600;
}

.dimension-weight {
  font-size: 13px;
  color: var(--color-accent);
  font-weight: 600;
}

.dimension-bar {
  height: 6px;
  background: var(--color-border-light);
  border-radius: 3px;
}

.dimension-fill {
  height: 100%;
  background: var(--color-accent);
  border-radius: 3px;
  transition: width 1s ease;
}

.dimension p {
  font-size: 13px;
  color: var(--color-ink-muted);
  margin-top: 4px;
}

.yuli-note {
  margin-top: 24px;
  font-size: 13px;
  color: var(--color-ink-muted);
}

/* ========================================
   More Features
   ======================================== */

.more-features {
  padding: 100px 0;
}

.feature-list {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 20px;
}

.feature-list-item {
  display: flex;
  gap: 16px;
  background: var(--color-surface);
  border: 1px solid var(--color-border-light);
  border-radius: var(--radius-md);
  padding: 24px;
  transition: all 0.3s ease;
}

.feature-list-item:hover {
  border-color: var(--color-border);
  box-shadow: var(--shadow-sm);
}

.feature-list-icon {
  width: 44px;
  height: 44px;
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: var(--font-serif);
  font-weight: 700;
  font-size: 18px;
  flex-shrink: 0;
}

.feature-list-icon.sub { background: #ede9fe; color: #7c3aed; }
.feature-list-icon.ins { background: #fce7f3; color: #db2777; }
.feature-list-icon.inv { background: var(--color-accent-light); color: var(--color-accent); }
.feature-list-icon.lend { background: #fef3c7; color: #d97706; }
.feature-list-icon.temp { background: #e0f2fe; color: #0284c7; }
.feature-list-icon.credit { background: #ffedd5; color: var(--color-credit); }

.feature-list-body h4 {
  font-size: 16px;
  font-weight: 600;
  margin-bottom: 4px;
}

.feature-list-body p {
  font-size: 14px;
  color: var(--color-ink-secondary);
  line-height: 1.6;
}

/* ========================================
   Security Section
   ======================================== */

.security-section {
  padding: 100px 0;
  background: var(--color-surface);
}

.security-content h2 {
  font-family: var(--font-serif);
  font-size: 32px;
  font-weight: 700;
}

.security-content > p {
  margin-top: 16px;
  color: var(--color-ink-secondary);
  font-size: 15px;
  line-height: 1.8;
  max-width: 640px;
}

.security-list {
  list-style: none;
  margin-top: 32px;
  display: flex;
  flex-direction: column;
  gap: 20px;
}

.security-list li {
  display: flex;
  gap: 16px;
  align-items: flex-start;
}

.security-list svg {
  width: 24px;
  height: 24px;
  color: var(--color-accent);
  flex-shrink: 0;
  margin-top: 2px;
}

.security-list strong {
  display: block;
  font-size: 15px;
  margin-bottom: 2px;
}

.security-list span {
  font-size: 14px;
  color: var(--color-ink-secondary);
}

/* ========================================
   CTA Section
   ======================================== */

.cta-section {
  padding: 100px 0;
}

.cta-content {
  text-align: center;
}

.cta-content h2 {
  font-family: var(--font-serif);
  font-size: 36px;
  font-weight: 700;
}

.cta-content p {
  margin-top: 12px;
  color: var(--color-ink-secondary);
  font-size: 16px;
}

.cta-content .btn {
  margin-top: 32px;
}

/* ========================================
   Footer
   ======================================== */

.footer {
  background: var(--color-ink);
  color: #fff;
  padding: 64px 0 32px;
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 48px;
}

.footer-logo {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 12px;
}

.footer-logo .logo-text {
  color: #fff;
}

.footer-brand p {
  font-size: 14px;
  color: rgba(255,255,255,0.5);
}

.footer-col h4 {
  font-size: 13px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: rgba(255,255,255,0.4);
  margin-bottom: 16px;
}

.footer-col a {
  display: block;
  font-size: 14px;
  color: rgba(255,255,255,0.7);
  padding: 4px 0;
  transition: color var(--transition);
}

.footer-col a:hover { color: #fff; }

.footer-bottom {
  margin-top: 48px;
  padding-top: 24px;
  border-top: 1px solid rgba(255,255,255,0.1);
}

.footer-bottom p {
  font-size: 13px;
  color: rgba(255,255,255,0.3);
}

/* ========================================
   Legal Pages
   ======================================== */

.legal-page {
  background: var(--color-surface);
}

.legal-main {
  padding-top: 64px;
}

.legal-hero {
  padding: 72px 0 44px;
  background: var(--color-bg);
  border-bottom: 1px solid var(--color-border-light);
}

.legal-kicker {
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--color-accent);
  margin-bottom: 12px;
}

.legal-hero h1 {
  font-family: var(--font-serif);
  font-size: 42px;
  font-weight: 700;
  line-height: 1.2;
  color: var(--color-ink);
}

.legal-hero p:not(.legal-kicker) {
  margin-top: 14px;
  color: var(--color-ink-secondary);
  font-size: 15px;
}

.legal-content {
  max-width: 860px;
  margin: 0 auto;
  padding: 48px 24px 88px;
}

.legal-content section {
  padding: 34px 0;
  border-bottom: 1px solid var(--color-border-light);
}

.legal-content section:first-child {
  padding-top: 0;
}

.legal-content section:last-child {
  border-bottom: none;
}

.legal-content h2 {
  font-family: var(--font-serif);
  font-size: 24px;
  font-weight: 700;
  margin-bottom: 14px;
  color: var(--color-ink);
}

.legal-content p,
.legal-content li {
  font-size: 15px;
  line-height: 1.85;
  color: var(--color-ink-secondary);
}

.legal-content p + p,
.legal-content p + ul,
.legal-content ul + p,
.legal-table-wrap + p {
  margin-top: 14px;
}

.legal-content ul {
  padding-left: 20px;
}

.legal-content a {
  color: var(--color-accent);
  text-decoration: underline;
  text-underline-offset: 3px;
}

.legal-table-wrap {
  overflow-x: auto;
  margin-top: 18px;
  border: 1px solid var(--color-border-light);
  border-radius: var(--radius-md);
  background: var(--color-bg);
}

.legal-table {
  width: 100%;
  min-width: 620px;
  border-collapse: collapse;
}

.legal-table th,
.legal-table td {
  padding: 14px 16px;
  text-align: left;
  border-bottom: 1px solid var(--color-border-light);
  font-size: 14px;
  line-height: 1.6;
}

.legal-table th {
  color: var(--color-ink);
  font-weight: 600;
  background: rgba(246, 242, 232, 0.72);
}

.legal-table td {
  color: var(--color-ink-secondary);
}

.legal-table tr:last-child td {
  border-bottom: none;
}

/* ========================================
   Responsive
   ======================================== */

@media (max-width: 968px) {
  .hero-container {
    grid-template-columns: 1fr;
    text-align: center;
  }

  .hero-subtitle { max-width: 100%; }
  .hero-actions { justify-content: center; }
  .hero-stats { justify-content: center; }
  .hero-visual { margin-top: 20px; }

  .features-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .screen-gallery {
    grid-template-columns: 1fr;
    gap: 24px;
  }

  .yuli-layout {
    grid-template-columns: 1fr;
    gap: 48px;
  }

  .yuli-visual { order: -1; }

  .feature-list {
    grid-template-columns: 1fr;
  }

  .footer-grid {
    grid-template-columns: 1fr 1fr;
    gap: 32px;
  }
}

/* Scroll Animations */
.animate-in {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 0.5s ease, transform 0.5s ease;
}

.animate-in.visible {
  opacity: 1;
  transform: translateY(0);
}

@media (max-width: 640px) {
  .nav-links { display: none; }
  .nav-toggle { display: flex; }

  .nav-links.open {
    display: flex;
    flex-direction: column;
    position: absolute;
    top: 64px;
    left: 0;
    right: 0;
    background: var(--color-bg);
    padding: 16px 24px;
    border-bottom: 1px solid var(--color-border);
    gap: 12px;
  }

  .hero-title { font-size: 36px; }
  .hero-actions { flex-direction: column; }
  .hero-stats { flex-wrap: wrap; }

  .phone-mockup { width: 240px; }
  .phone-mockup-small { width: 210px; }
  .phone-mockup-yuli { width: 240px; }

  .features-grid { grid-template-columns: 1fr; }

  .section-header h2 { font-size: 26px; }
  .cta-content h2 { font-size: 28px; }
  .legal-hero h1 { font-size: 34px; }
  .legal-content { padding-top: 32px; }

  .footer-grid { grid-template-columns: 1fr; gap: 24px; }
}