/* ============================================================================
 * 云聊 (YunChat) 官方网站 — UI/UX Pro Max Glassmorphism Design System
 * Style ID: glassmorphism + liquid-glass
 * - Multi-orb vibrant aurora background (Blue #2563EB, Indigo #6366F1, Cyan #06B6D4, Emerald #10B981)
 * - Frosted glass cards: backdrop-filter: blur(18px) saturate(185%), 1px specular white border,
 *   top light-source reflection (inset 0 1px 0 rgba(255,255,255,0.92)), layered Z-depth shadows
 * - Crisp Lucide SVG icons, tabular-nums, WCAG AA >= 4.5:1 contrast
 * ============================================================================ */

@import url('https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600;700;800&family=Plus+Jakarta+Sans:wght@500;600;700;800&display=swap');

:root {
  --blur-amount: 18px;
  --blur-strong: 24px;

  --primary: #2563eb;
  --primary-2: #6366f1;
  --accent: #059669;
  --cyan: #06b6d4;

  /* Compatibility aliases */
  --mint-50: rgba(37, 99, 235, 0.10);
  --mint-100: rgba(37, 99, 235, 0.16);
  --mint-500: #2563eb;
  --mint-600: #1d4ed8;
  --sky-50: rgba(99, 102, 241, 0.10);
  --sky-100: rgba(99, 102, 241, 0.16);
  --sky-500: #6366f1;
  --sky-600: #4f46e5;

  --text-dark: #0f172a;
  --text-body: #334155;
  --text-light: #64748b;

  --card-surface: linear-gradient(135deg, rgba(255, 255, 255, 0.58) 0%, rgba(255, 255, 255, 0.30) 100%);
  --card-surface-hover: linear-gradient(135deg, rgba(255, 255, 255, 0.74) 0%, rgba(255, 255, 255, 0.46) 100%);
  --card-border: rgba(255, 255, 255, 0.84);
  --card-border-strong: rgba(255, 255, 255, 0.96);
  --glass-highlight: inset 0 1px 1px rgba(255, 255, 255, 0.96), inset 0 -1px 1px rgba(255, 255, 255, 0.38);
  --shadow-soft: 0 20px 44px -10px rgba(37, 99, 235, 0.16), 0 6px 16px -2px rgba(15, 23, 42, 0.06);
  --shadow-hover: 0 28px 56px -12px rgba(37, 99, 235, 0.24), 0 10px 24px -4px rgba(15, 23, 42, 0.08);
}

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: "Inter", "Plus Jakarta Sans", -apple-system, BlinkMacSystemFont, "PingFang SC", "Hiragino Sans GB", "Noto Sans SC", sans-serif;
  color: var(--text-dark);
  background:
    radial-gradient(circle at 10% 14%, rgba(59, 130, 246, 0.52) 0%, transparent 40%),
    radial-gradient(circle at 88% 16%, rgba(124, 58, 237, 0.44) 0%, transparent 42%),
    radial-gradient(circle at 82% 76%, rgba(6, 182, 212, 0.42) 0%, transparent 44%),
    radial-gradient(circle at 18% 82%, rgba(99, 102, 241, 0.40) 0%, transparent 44%),
    radial-gradient(circle at 52% 46%, rgba(236, 72, 153, 0.22) 0%, transparent 50%),
    linear-gradient(135deg, #c7d9ff 0%, #dbeafe 38%, #e0e7ff 70%, #cffafe 100%);
  background-attachment: fixed;
  line-height: 1.65;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
}

/* 环境极光光晕层 (Ambient Aurora Orbs) */
.bg-blob {
  position: fixed;
  border-radius: 50%;
  filter: blur(68px);
  z-index: -1;
  pointer-events: none;
  opacity: 0.88;
}

.blob-1 {
  width: 520px;
  height: 520px;
  background: radial-gradient(circle, rgba(37, 99, 235, 0.68) 0%, rgba(124, 58, 237, 0.34) 65%, transparent 100%);
  top: -120px;
  left: -80px;
}

.blob-2 {
  width: 500px;
  height: 500px;
  background: radial-gradient(circle, rgba(124, 58, 237, 0.62) 0%, rgba(6, 182, 212, 0.36) 68%, transparent 100%);
  top: 18%;
  right: -90px;
}

.blob-3 {
  width: 460px;
  height: 460px;
  background: radial-gradient(circle, rgba(6, 182, 212, 0.56) 0%, rgba(59, 130, 246, 0.30) 68%, transparent 100%);
  bottom: -100px;
  left: 16%;
}

.container {
  max-width: 1180px;
  margin: 0 auto;
  padding: 0 24px;
}

/* 顶部悬浮液态毛玻璃导航栏 (Floating Liquid Glass Navbar) */
.navbar {
  position: sticky;
  top: 14px;
  z-index: 100;
  max-width: 1180px;
  margin: 14px auto 0;
  padding: 0 12px;
}

.nav-inner {
  height: 66px;
  padding: 0 22px;
  background: rgba(255, 255, 255, 0.58);
  backdrop-filter: blur(var(--blur-strong)) saturate(195%);
  -webkit-backdrop-filter: blur(var(--blur-strong)) saturate(195%);
  border: 1px solid var(--card-border-strong);
  border-radius: 22px;
  box-shadow: 0 14px 36px -8px rgba(37, 99, 235, 0.12), var(--glass-highlight);
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.brand {
  display: flex;
  align-items: center;
  gap: 12px;
  text-decoration: none;
  color: var(--text-dark);
}

.brand-logo {
  width: 40px;
  height: 40px;
  border-radius: 13px;
  background: linear-gradient(135deg, var(--primary) 0%, var(--primary-2) 100%);
  border: 1px solid rgba(255, 255, 255, 0.5);
  color: #ffffff;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 19px;
  font-weight: 800;
  box-shadow: 0 8px 18px -4px rgba(37, 99, 235, 0.42), inset 0 1px 0 rgba(255, 255, 255, 0.5);
}

.brand-name {
  font-size: 19px;
  font-weight: 800;
  letter-spacing: -0.02em;
}

.brand-sub {
  font-size: 11.5px;
  color: var(--mint-600);
  background: rgba(37, 99, 235, 0.12);
  border: 1px solid rgba(37, 99, 235, 0.22);
  padding: 2px 10px;
  border-radius: 999px;
  font-weight: 600;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 28px;
}

.nav-links a {
  text-decoration: none;
  color: var(--text-body);
  font-size: 14.5px;
  font-weight: 600;
  transition: color 0.2s ease;
}

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

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

/* 按钮体系 (Glass & Luminous Buttons) */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 10px 20px;
  border-radius: 14px;
  font-size: 14px;
  font-weight: 600;
  text-decoration: none;
  cursor: pointer;
  border: 1px solid transparent;
  transition: all 200ms cubic-bezier(0.22, 1, 0.36, 1);
}

.btn svg {
  width: 17px;
  height: 17px;
  stroke: currentColor;
  stroke-width: 2;
  fill: none;
  flex-shrink: 0;
}

.btn:hover {
  transform: translateY(-2px);
}

.btn:focus-visible {
  outline: 2px solid var(--primary);
  outline-offset: 2px;
}

.btn-mint {
  background: linear-gradient(135deg, var(--primary) 0%, var(--primary-2) 100%);
  border-color: rgba(255, 255, 255, 0.42);
  color: #ffffff;
  box-shadow: 0 10px 24px -6px rgba(37, 99, 235, 0.42), inset 0 1px 0 rgba(255, 255, 255, 0.48);
}

.btn-mint:hover {
  box-shadow: 0 14px 28px -6px rgba(37, 99, 235, 0.54), inset 0 1px 0 rgba(255, 255, 255, 0.6);
}

.btn-outline {
  background: rgba(255, 255, 255, 0.62);
  backdrop-filter: blur(14px) saturate(180%);
  -webkit-backdrop-filter: blur(14px) saturate(180%);
  color: var(--text-dark);
  border: 1px solid var(--card-border-strong);
  box-shadow: 0 4px 14px rgba(37, 99, 235, 0.06), var(--glass-highlight);
}

.btn-outline:hover {
  background: rgba(255, 255, 255, 0.86);
  border-color: rgba(37, 99, 235, 0.35);
  color: var(--primary);
}

.btn-lg {
  padding: 13px 24px;
  font-size: 15px;
  border-radius: 16px;
}

/* Hero 首屏区域 */
.hero {
  padding: 52px 0 72px;
}

.hero-grid {
  display: grid;
  grid-template-columns: 1.15fr 0.85fr;
  gap: 40px;
  align-items: center;
}

.hero-grid > div:first-child {
  background: linear-gradient(135deg, rgba(255, 255, 255, 0.56) 0%, rgba(255, 255, 255, 0.28) 100%);
  backdrop-filter: blur(24px) saturate(200%);
  -webkit-backdrop-filter: blur(24px) saturate(200%);
  border: 1px solid rgba(255, 255, 255, 0.88);
  border-radius: 32px;
  padding: 38px 36px;
  box-shadow: 0 24px 56px -12px rgba(37, 99, 235, 0.18), var(--glass-highlight);
}

@media (max-width: 900px) {
  .hero-grid {
    grid-template-columns: 1fr;
    text-align: center;
  }
  .nav-links {
    display: none;
  }
  .hero-badges, .hero-actions, .hero-metrics {
    justify-content: center;
  }
  .hero-desc {
    margin-left: auto;
    margin-right: auto;
  }
}

.fresh-pill {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: rgba(255, 255, 255, 0.64);
  backdrop-filter: blur(14px) saturate(180%);
  -webkit-backdrop-filter: blur(14px) saturate(180%);
  border: 1px solid var(--card-border-strong);
  box-shadow: 0 6px 18px rgba(37, 99, 235, 0.08), var(--glass-highlight);
  color: var(--mint-600);
  padding: 7px 16px;
  border-radius: 999px;
  font-size: 13px;
  font-weight: 600;
  margin-bottom: 22px;
}

.fresh-pill-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: #10b981;
  box-shadow: 0 0 10px #10b981;
}

.hero-title {
  font-size: clamp(34px, 4.2vw, 48px);
  font-weight: 800;
  line-height: 1.2;
  letter-spacing: -0.025em;
  color: var(--text-dark);
  margin-bottom: 18px;
}

.hero-title .gradient-text {
  background: linear-gradient(135deg, #2563eb 0%, #6366f1 55%, #059669 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.hero-desc {
  font-size: 16.5px;
  color: var(--text-body);
  max-width: 560px;
  margin-bottom: 28px;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-bottom: 34px;
}

/* 毛玻璃指标矩阵条 (Frosted Metrics Strip) */
.hero-metrics {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 12px;
  padding: 18px 20px;
  background: var(--card-surface);
  backdrop-filter: blur(var(--blur-amount)) saturate(185%);
  -webkit-backdrop-filter: blur(var(--blur-amount)) saturate(185%);
  border: 1px solid var(--card-border);
  border-radius: 20px;
  box-shadow: var(--shadow-soft), var(--glass-highlight);
}

@media (max-width: 600px) {
  .hero-metrics {
    grid-template-columns: repeat(2, 1fr);
  }
}

.metric-item {
  display: flex;
  flex-direction: column;
}

.metric-val {
  font-size: 21px;
  font-weight: 800;
  background: linear-gradient(135deg, var(--primary), var(--primary-2));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  font-variant-numeric: tabular-nums;
}

.metric-label {
  font-size: 12px;
  font-weight: 500;
  color: var(--text-body);
  margin-top: 2px;
}

/* 右侧光学玻璃真机交互预览框 (Optical Glass Phone Frame) */
.mockup-wrapper {
  display: flex;
  flex-direction: column;
  align-items: center;
}

.phone-frame {
  width: 362px;
  height: 696px;
  padding: 10px;
  background: rgba(255, 255, 255, 0.46);
  backdrop-filter: blur(26px) saturate(195%);
  -webkit-backdrop-filter: blur(26px) saturate(195%);
  border-radius: 44px;
  border: 1.5px solid rgba(255, 255, 255, 0.92);
  box-shadow:
    0 30px 68px -12px rgba(37, 99, 235, 0.22),
    0 12px 28px -6px rgba(15, 23, 42, 0.08),
    inset 0 1px 0 rgba(255, 255, 255, 0.96);
  overflow: hidden;
  position: relative;
}

.phone-frame iframe {
  width: 100%;
  height: 100%;
  border: none;
  border-radius: 34px;
  background: #e8f0fe;
}

.mockup-caption {
  margin-top: 14px;
  padding: 6px 14px;
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.56);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border: 1px solid var(--card-border);
  font-size: 12.5px;
  font-weight: 500;
  color: var(--text-body);
  display: inline-flex;
  align-items: center;
  gap: 6px;
}

.mockup-caption svg {
  width: 15px;
  height: 15px;
  stroke: var(--primary);
  stroke-width: 2;
  fill: none;
}

/* 通用区块标题 */
.section {
  padding: 68px 0;
}

.section-head {
  text-align: center;
  max-width: 640px;
  margin: 0 auto 44px;
}

.section-tag {
  display: inline-block;
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.06em;
  color: var(--primary);
  background: rgba(255, 255, 255, 0.65);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border: 1px solid var(--card-border-strong);
  box-shadow: var(--glass-highlight);
  padding: 5px 14px;
  border-radius: 999px;
  margin-bottom: 12px;
}

.section-title {
  font-size: clamp(26px, 3vw, 32px);
  font-weight: 800;
  letter-spacing: -0.02em;
  color: var(--text-dark);
  margin-bottom: 10px;
}

.section-sub {
  font-size: 15px;
  color: var(--text-body);
}

/* 产品特色网格 (6 大毛玻璃卡片) */
.features-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(310px, 1fr));
  gap: 22px;
}

.glass-card {
  background: var(--card-surface);
  backdrop-filter: blur(var(--blur-amount)) saturate(185%);
  -webkit-backdrop-filter: blur(var(--blur-amount)) saturate(185%);
  border: 1px solid var(--card-border);
  border-radius: 24px;
  padding: 28px;
  box-shadow: var(--shadow-soft), var(--glass-highlight);
  transition: transform 220ms cubic-bezier(0.22, 1, 0.36, 1), box-shadow 220ms ease, background-color 220ms ease;
}

.glass-card:hover {
  background: var(--card-surface-hover);
  transform: translateY(-4px);
  box-shadow: var(--shadow-hover), var(--glass-highlight);
}

.feature-icon {
  width: 50px;
  height: 50px;
  border-radius: 16px;
  border: 1px solid rgba(255, 255, 255, 0.88);
  box-shadow: 0 8px 18px -4px rgba(37, 99, 235, 0.14), var(--glass-highlight);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 18px;
}

.feature-icon svg {
  width: 24px;
  height: 24px;
  stroke: currentColor;
  stroke-width: 1.85;
  fill: none;
}

.feature-title {
  font-size: 18px;
  font-weight: 700;
  margin-bottom: 8px;
  color: var(--text-dark);
}

.feature-desc {
  font-size: 14px;
  color: var(--text-body);
  line-height: 1.65;
}

/* 多端下载中心 (4 大平台毛玻璃卡片) */
.download-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(255px, 1fr));
  gap: 20px;
}

.dl-card {
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  position: relative;
  overflow: hidden;
}

.dl-badge {
  position: absolute;
  top: 18px;
  right: 18px;
  font-size: 11px;
  font-weight: 700;
  padding: 4px 11px;
  border-radius: 999px;
  border: 1px solid rgba(255, 255, 255, 0.75);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
}

.dl-platform-icon {
  width: 52px;
  height: 52px;
  border-radius: 16px;
  border: 1px solid rgba(255, 255, 255, 0.88);
  box-shadow: 0 8px 18px -4px rgba(37, 99, 235, 0.14), var(--glass-highlight);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 18px;
}

.dl-platform-icon svg {
  width: 25px;
  height: 25px;
  stroke: currentColor;
  stroke-width: 1.85;
  fill: none;
}

.dl-title {
  font-size: 18px;
  font-weight: 700;
  margin-bottom: 6px;
  color: var(--text-dark);
}

.dl-version {
  font-size: 12px;
  color: var(--text-light);
  font-family: ui-monospace, SFMono-Regular, Menlo, monospace;
  font-variant-numeric: tabular-nums;
  margin-bottom: 12px;
}

.dl-desc {
  font-size: 13.5px;
  color: var(--text-body);
  margin-bottom: 22px;
  flex: 1;
}

.dl-btn-group {
  display: flex;
  flex-direction: column;
  gap: 10px;
}

/* 底部毛玻璃页脚 */
.footer {
  margin-top: 24px;
  padding: 36px 0;
  background: rgba(255, 255, 255, 0.42);
  backdrop-filter: blur(16px) saturate(180%);
  -webkit-backdrop-filter: blur(16px) saturate(180%);
  border-top: 1px solid var(--card-border);
  box-shadow: var(--glass-highlight);
  text-align: center;
  color: var(--text-body);
  font-size: 13.5px;
}

/* 二维码与下载引导毛玻璃弹窗 */
.qr-modal-backdrop {
  position: fixed;
  inset: 0;
  background: rgba(15, 23, 42, 0.36);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  display: none;
  align-items: center;
  justify-content: center;
  z-index: 200;
  padding: 20px;
}

.qr-modal-backdrop.show {
  display: flex;
}

.qr-modal-card {
  background: rgba(255, 255, 255, 0.78);
  backdrop-filter: blur(28px) saturate(200%);
  -webkit-backdrop-filter: blur(28px) saturate(200%);
  border: 1px solid var(--card-border-strong);
  border-radius: 26px;
  padding: 30px 28px;
  max-width: 400px;
  width: 100%;
  text-align: center;
  box-shadow: 0 28px 60px -12px rgba(15, 23, 42, 0.24), var(--glass-highlight);
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    transition-duration: 0.01ms !important;
    animation-duration: 0.01ms !important;
  }
}