/* ===== 比特浏览器 - 现代化全局样式 ===== */
:root {
  --bg-primary: #0a0e27;
  --bg-secondary: #111640;
  --bg-card: rgba(22, 27, 67, 0.7);
  --accent: #4facfe;
  --accent2: #00f2fe;
  --accent-gradient: linear-gradient(135deg, #4facfe, #00f2fe);
  --primary-gradient: linear-gradient(135deg, #667eea, #764ba2);
  --text-primary: #e8ecf4;
  --text-secondary: #8b93a7;
  --border: rgba(79, 172, 254, 0.12);
  --border-hover: rgba(79, 172, 254, 0.3);
  --glow: 0 0 40px rgba(79, 172, 254, 0.15);
  --shadow-card: 0 8px 40px rgba(0, 0, 0, 0.3);
  --radius: 16px;
  --radius-sm: 10px;
  --transition: 0.35s cubic-bezier(0.4, 0, 0.2, 1);
}

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

html { scroll-behavior: smooth; }

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang SC',
    'Microsoft YaHei', sans-serif;
  background: var(--bg-primary);
  color: var(--text-primary);
  min-height: 100vh;
  line-height: 1.6;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
}

/* ===== 背景动态效果 ===== */
.bg-mesh {
  position: fixed;
  inset: 0;
  z-index: 0;
  pointer-events: none;
  overflow: hidden;
}
.bg-mesh::before {
  content: '';
  position: absolute;
  top: -50%;
  left: -50%;
  width: 200%;
  height: 200%;
  background:
    radial-gradient(ellipse at 20% 50%, rgba(79, 172, 254, 0.08) 0%, transparent 50%),
    radial-gradient(ellipse at 80% 20%, rgba(102, 126, 234, 0.08) 0%, transparent 50%),
    radial-gradient(ellipse at 50% 80%, rgba(0, 242, 254, 0.06) 0%, transparent 50%);
  animation: bgFloat 20s ease-in-out infinite;
}
@keyframes bgFloat {
  0%, 100% { transform: translate(0, 0); }
  50% { transform: translate(2%, 1%); }
}

/* 网格噪点叠加 */
.bg-mesh::after {
  content: '';
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(79, 172, 254, 0.03) 1px, transparent 1px),
    linear-gradient(90deg, rgba(79, 172, 254, 0.03) 1px, transparent 1px);
  background-size: 60px 60px;
}

.page-wrapper {
  position: relative;
  z-index: 1;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

/* ===== Header ===== */
.main-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(10, 14, 39, 0.85);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--border);
  transition: var(--transition);
}
.header-content {
  max-width: 1200px;
  margin: 0 auto;
  padding: 16px 24px;
  display: flex;
  justify-content: space-between;
  align-items: center;
}
.site-logo {
  display: flex;
  align-items: center;
  gap: 12px;
  text-decoration: none;
  color: var(--text-primary);
  transition: var(--transition);
}
.site-logo:hover { transform: scale(1.02); }
.logo-icon { font-size: 30px; line-height: 1; }
.logo-text {
  font-size: 20px;
  font-weight: 700;
  background: var(--accent-gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}
.main-nav { display: flex; gap: 8px; }
.nav-link {
  color: var(--text-secondary);
  text-decoration: none;
  font-size: 15px;
  font-weight: 500;
  padding: 10px 22px;
  border-radius: 50px;
  transition: var(--transition);
  position: relative;
}
.nav-link:hover { color: var(--text-primary); background: rgba(79, 172, 254, 0.08); }
.nav-link.active {
  color: #fff;
  background: rgba(79, 172, 254, 0.15);
}

/* ===== Main ===== */
.main-content { flex: 1; }

/* ===== Section ===== */
.section-header {
  text-align: center;
  margin-bottom: 56px;
}
.section-tag {
  display: inline-block;
  padding: 6px 18px;
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--accent);
  background: rgba(79, 172, 254, 0.08);
  border: 1px solid rgba(79, 172, 254, 0.18);
  border-radius: 50px;
  margin-bottom: 16px;
}
.section-title {
  font-size: 40px;
  font-weight: 800;
  letter-spacing: -0.02em;
  background: linear-gradient(180deg, #fff 0%, var(--text-secondary) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}
.section-desc {
  color: var(--text-secondary);
  font-size: 17px;
  margin-top: 12px;
  max-width: 480px;
  margin-left: auto;
  margin-right: auto;
}

/* ===== Container ===== */
.container {
  max-width: 1140px;
  margin: 0 auto;
  padding: 0 24px;
}

/* ===== Buttons ===== */
.btn-primary {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 16px 40px;
  background: var(--accent-gradient);
  color: #0a0e27;
  text-decoration: none;
  border-radius: 50px;
  font-size: 16px;
  font-weight: 700;
  border: none;
  cursor: pointer;
  transition: var(--transition);
  position: relative;
  overflow: hidden;
}
.btn-primary::before {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, rgba(255,255,255,0.2), transparent);
  opacity: 0;
  transition: opacity 0.3s;
}
.btn-primary:hover {
  transform: translateY(-3px);
  box-shadow: 0 12px 36px rgba(79, 172, 254, 0.35);
}
.btn-primary:hover::before { opacity: 1; }
.btn-large { padding: 20px 56px; font-size: 18px; }
.btn-outline {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 14px 36px;
  background: transparent;
  color: var(--text-primary);
  text-decoration: none;
  border-radius: 50px;
  font-size: 16px;
  font-weight: 600;
  border: 2px solid rgba(79, 172, 254, 0.3);
  cursor: pointer;
  transition: var(--transition);
}
.btn-outline:hover {
  border-color: var(--accent);
  background: rgba(79, 172, 254, 0.08);
  transform: translateY(-2px);
}

/* ===== Hero ===== */
.hero-section {
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 90vh;
  padding: 80px 24px;
  text-align: center;
  overflow: hidden;
}
.hero-orb {
  position: absolute;
  border-radius: 50%;
  filter: blur(120px);
  opacity: 0.3;
  pointer-events: none;
}
.hero-orb--1 {
  width: 500px; height: 500px;
  background: var(--accent);
  top: -100px; left: -150px;
  animation: orbPulse1 8s ease-in-out infinite;
}
.hero-orb--2 {
  width: 400px; height: 400px;
  background: #764ba2;
  bottom: -80px; right: -120px;
  animation: orbPulse2 10s ease-in-out infinite;
}
@keyframes orbPulse1 {
  0%, 100% { transform: translate(0, 0) scale(1); }
  50% { transform: translate(40px, 30px) scale(1.15); }
}
@keyframes orbPulse2 {
  0%, 100% { transform: translate(0, 0) scale(0.9); }
  50% { transform: translate(-30px, -20px) scale(1.1); }
}
.hero-inner {
  position: relative;
  z-index: 1;
  max-width: 700px;
}
.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 8px 20px;
  background: rgba(79, 172, 254, 0.1);
  border: 1px solid rgba(79, 172, 254, 0.2);
  border-radius: 50px;
  font-size: 13px;
  font-weight: 500;
  color: var(--accent);
  margin-bottom: 28px;
}
.hero-badge .dot {
  width: 8px; height: 8px;
  background: #4ade80;
  border-radius: 50%;
  animation: dotPulse 2s ease-in-out infinite;
}
@keyframes dotPulse {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.4; }
}
.hero-title {
  font-size: clamp(42px, 7vw, 72px);
  font-weight: 900;
  line-height: 1.1;
  letter-spacing: -0.03em;
  margin-bottom: 20px;
  background: linear-gradient(135deg, #fff 20%, #4facfe 50%, #00f2fe 80%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}
.hero-subtitle {
  font-size: 20px;
  color: var(--text-secondary);
  margin-bottom: 40px;
  line-height: 1.6;
}
.hero-actions {
  display: flex;
  gap: 16px;
  justify-content: center;
  flex-wrap: wrap;
}
.hero-clients {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 16px;
  margin-top: 48px;
  color: var(--text-secondary);
  font-size: 14px;
}
.hero-clients .avatars {
  display: flex;
}
.hero-clients .avatars span {
  width: 34px; height: 34px;
  border-radius: 50%;
  background: var(--accent-gradient);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 14px;
  margin-right: -10px;
  border: 2px solid var(--bg-primary);
  font-weight: 600;
  color: #0a0e27;
}

/* ===== Stats ===== */
.stats-section {
  padding: 40px 24px;
  position: relative;
}
.stats-grid {
  max-width: 900px;
  margin: 0 auto;
  display: flex;
  justify-content: center;
  gap: 0;
  background: var(--bg-card);
  backdrop-filter: blur(20px);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
}
.stat-item {
  flex: 1;
  text-align: center;
  padding: 36px 28px;
  position: relative;
}
.stat-item + .stat-item { border-left: 1px solid var(--border); }
.stat-icon {
  font-size: 24px;
  margin-bottom: 8px;
}
.stat-number {
  font-size: 42px;
  font-weight: 800;
  background: var(--accent-gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  line-height: 1.2;
}
.stat-label {
  color: var(--text-secondary);
  font-size: 14px;
  margin-top: 4px;
}

/* ===== Features ===== */
.features-section {
  padding: 80px 24px;
}
.features-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 24px;
  max-width: 1100px;
  margin: 0 auto;
}
.feature-card {
  background: var(--bg-card);
  backdrop-filter: blur(20px);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 36px 28px;
  transition: var(--transition);
  position: relative;
  overflow: hidden;
}
.feature-card::after {
  content: '';
  position: absolute;
  top: -50%; right: -50%;
  width: 200px; height: 200px;
  background: radial-gradient(circle, rgba(79, 172, 254, 0.08), transparent);
  border-radius: 50%;
  transition: var(--transition);
}
.feature-card:hover {
  transform: translateY(-6px);
  border-color: var(--border-hover);
  box-shadow: var(--glow);
}
.feature-card:hover::after {
  transform: scale(1.5);
}
.feature-icon-wrap {
  width: 56px; height: 56px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: rgba(79, 172, 254, 0.1);
  border-radius: 14px;
  margin-bottom: 20px;
  font-size: 26px;
}
.feature-card h3 {
  font-size: 19px;
  font-weight: 700;
  margin-bottom: 10px;
}
.feature-card p {
  color: var(--text-secondary);
  font-size: 14px;
  line-height: 1.7;
}

/* ===== Detail Cards ===== */
.detail-section {
  padding: 80px 24px;
  background: var(--bg-secondary);
}
.detail-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
  gap: 28px;
  max-width: 1100px;
  margin: 0 auto;
}
.detail-card {
  background: var(--bg-card);
  backdrop-filter: blur(20px);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 36px 32px;
  transition: var(--transition);
}
.detail-card:hover {
  transform: translateY(-4px);
  border-color: var(--border-hover);
  box-shadow: var(--glow);
}
.detail-card h3 {
  font-size: 20px;
  font-weight: 700;
  margin-bottom: 22px;
  display: flex;
  align-items: center;
  gap: 10px;
}
.detail-card h3 .dc-icon {
  font-size: 22px;
}
.detail-card ul {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 14px;
}
.detail-card li {
  display: flex;
  align-items: center;
  gap: 10px;
  color: var(--text-secondary);
  font-size: 15px;
  padding: 10px 14px;
  background: rgba(255, 255, 255, 0.02);
  border-radius: 8px;
  transition: var(--transition);
}
.detail-card li:hover {
  background: rgba(79, 172, 254, 0.06);
  color: var(--text-primary);
}
.detail-card li .check {
  width: 20px; height: 20px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: rgba(74, 222, 128, 0.15);
  border-radius: 50%;
  font-size: 11px;
  color: #4ade80;
  flex-shrink: 0;
}

/* ===== Compare ===== */
.compare-section {
  padding: 80px 24px;
}
.compare-table {
  max-width: 800px;
  margin: 0 auto;
  overflow: hidden;
  border-radius: var(--radius);
  border: 1px solid var(--border);
}
.compare-table table {
  width: 100%;
  border-collapse: collapse;
}
.compare-table th {
  padding: 18px 24px;
  text-align: left;
  font-size: 14px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  color: var(--text-secondary);
  background: rgba(79, 172, 254, 0.06);
}
.compare-table td {
  padding: 16px 24px;
  border-top: 1px solid var(--border);
  font-size: 15px;
  color: var(--text-secondary);
}
.compare-table tr:last-child td { border-bottom: none; }
.compare-table tbody tr {
  transition: var(--transition);
}
.compare-table tbody tr:hover { background: rgba(79, 172, 254, 0.04); }
.compare-table td.highlight { color: #4ade80; font-weight: 600; }

/* ===== FAQ ===== */
.faq-section {
  padding: 80px 24px;
  background: var(--bg-secondary);
}
.faq-grid {
  max-width: 780px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 14px;
}
.faq-item {
  background: var(--bg-card);
  backdrop-filter: blur(20px);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 24px 28px;
  cursor: pointer;
  transition: var(--transition);
}
.faq-item:hover {
  border-color: var(--border-hover);
}
.faq-item h4 {
  font-size: 16px;
  font-weight: 600;
  display: flex;
  align-items: center;
  gap: 10px;
}
.faq-item h4 .faq-q {
  color: var(--accent);
  font-weight: 700;
}
.faq-item p {
  color: var(--text-secondary);
  font-size: 14px;
  line-height: 1.7;
  margin-top: 10px;
  padding-left: 32px;
}

/* ===== CTA ===== */
.cta-section {
  padding: 100px 24px;
  text-align: center;
  position: relative;
  overflow: hidden;
}
.cta-section::before {
  content: '';
  position: absolute;
  width: 600px; height: 600px;
  background: radial-gradient(circle, rgba(79, 172, 254, 0.15), transparent);
  top: 50%; left: 50%;
  transform: translate(-50%, -50%);
  pointer-events: none;
}
.cta-content { position: relative; z-index: 1; }
.cta-content h2 {
  font-size: 42px;
  font-weight: 800;
  margin-bottom: 16px;
  letter-spacing: -0.02em;
}
.cta-content p {
  color: var(--text-secondary);
  font-size: 18px;
  margin-bottom: 36px;
}

/* ===== Download Page ===== */
.download-section {
  padding: 60px 24px;
  display: flex;
  justify-content: center;
}
.download-card {
  background: var(--bg-card);
  backdrop-filter: blur(20px);
  border: 1px solid var(--border);
  border-radius: 24px;
  padding: 48px 44px;
  text-align: center;
  max-width: 520px;
  width: 100%;
}
.download-icon { font-size: 56px; margin-bottom: 16px; }
.download-title {
  font-size: 32px;
  font-weight: 800;
  background: var(--accent-gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  margin-bottom: 8px;
}
.download-subtitle { color: var(--text-secondary); font-size: 15px; margin-bottom: 32px; }
.download-info {
  background: rgba(0, 0, 0, 0.2);
  border-radius: var(--radius-sm);
  padding: 24px;
  margin-bottom: 32px;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
}
.info-item { text-align: left; }
.info-label {
  display: block;
  font-size: 12px;
  color: var(--text-secondary);
  text-transform: uppercase;
  letter-spacing: 0.06em;
  margin-bottom: 4px;
}
.info-value { font-size: 15px; font-weight: 600; }
.download-section .btn-back {
  display: inline-block;
  margin-top: 20px;
  color: var(--text-secondary);
  font-size: 14px;
  text-decoration: none;
  transition: var(--transition);
}
.download-section .btn-back:hover { color: var(--accent); }

/* ===== Install Steps ===== */
.install-section {
  padding: 80px 24px;
  background: var(--bg-secondary);
}
.steps-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 32px;
  max-width: 1000px;
  margin: 0 auto;
}
.step-item {
  text-align: center;
  position: relative;
}
.step-item + .step-item::before {
  content: '';
  position: absolute;
  top: 28px;
  left: -20px;
  width: 40px;
  height: 2px;
  background: var(--border);
}
.step-number {
  width: 56px; height: 56px;
  margin: 0 auto 16px;
  background: var(--accent-gradient);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 22px;
  font-weight: 800;
  color: #0a0e27;
}
.step-content h3 {
  font-size: 17px;
  font-weight: 700;
  margin-bottom: 6px;
}
.step-content p {
  color: var(--text-secondary);
  font-size: 14px;
}

/* ===== System Req ===== */
.sysreq-section {
  padding: 80px 24px;
}
.sysreq-content {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 40px;
  max-width: 800px;
  margin: 0 auto;
}
.sysreq-item {
  background: var(--bg-card);
  backdrop-filter: blur(20px);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 32px;
}
.sysreq-item h4 {
  font-size: 18px;
  font-weight: 700;
  margin-bottom: 20px;
  display: flex;
  align-items: center;
  gap: 8px;
}
.sysreq-item h4 .badge {
  font-size: 11px;
  padding: 3px 10px;
  border-radius: 20px;
  font-weight: 600;
  text-transform: uppercase;
}
.sysreq-item h4 .badge.min { background: rgba(251, 191, 36, 0.15); color: #fbbf24; }
.sysreq-item h4 .badge.rec { background: rgba(74, 222, 128, 0.15); color: #4ade80; }
.sysreq-item ul { list-style: none; display: flex; flex-direction: column; gap: 12px; }
.sysreq-item li {
  color: var(--text-secondary);
  font-size: 15px;
  display: flex;
  align-items: center;
  gap: 8px;
}

/* ===== Changelog ===== */
.changelog-section {
  padding: 80px 24px;
  background: var(--bg-secondary);
}
.changelog-content {
  max-width: 680px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 0;
}
.changelog-item {
  display: flex;
  align-items: center;
  gap: 16px;
  padding: 16px 20px;
  border-radius: 8px;
  transition: var(--transition);
  color: var(--text-secondary);
  font-size: 15px;
}
.changelog-item:hover {
  background: rgba(255, 255, 255, 0.02);
}
.changelog-tag {
  padding: 4px 12px;
  border-radius: 20px;
  font-size: 12px;
  font-weight: 600;
  flex-shrink: 0;
}
.changelog-tag.new { background: rgba(74, 222, 128, 0.15); color: #4ade80; }
.changelog-tag.optimize { background: rgba(79, 172, 254, 0.15); color: #4facfe; }
.changelog-tag.fix { background: rgba(251, 191, 36, 0.15); color: #fbbf24; }

/* ===== 404 Page ===== */
.error-section {
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 80vh;
  padding: 60px 24px;
  text-align: center;
}
.error-card { max-width: 500px; }
.error-icon { font-size: 80px; margin-bottom: 20px; }
.error-code {
  font-size: clamp(100px, 15vw, 160px);
  font-weight: 900;
  line-height: 1;
  background: linear-gradient(135deg, var(--accent), var(--accent2));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  opacity: 0.4;
}
.error-title {
  font-size: 28px;
  font-weight: 700;
  margin-top: -20px;
  margin-bottom: 12px;
}
.error-desc {
  color: var(--text-secondary);
  margin-bottom: 36px;
  font-size: 16px;
}
.error-actions {
  display: flex;
  gap: 16px;
  justify-content: center;
  flex-wrap: wrap;
}

/* ===== Footer ===== */
.main-footer {
  background: var(--bg-secondary);
  border-top: 1px solid var(--border);
  padding: 36px 24px;
  text-align: center;
}
.footer-content { max-width: 1200px; margin: 0 auto; }
.footer-content .footer-links {
  display: flex;
  justify-content: center;
  gap: 24px;
  margin-bottom: 12px;
}
.main-footer p { color: var(--text-secondary); font-size: 14px; }
.main-footer a {
  color: var(--text-secondary);
  text-decoration: none;
  font-size: 14px;
  transition: var(--transition);
}
.main-footer a:hover { color: var(--accent); }

/* ===== Reveal Animations ===== */
.reveal {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity 0.7s ease, transform 0.7s ease;
}
.revealed {
  opacity: 1;
  transform: translateY(0);
}

/* ===== Responsive ===== */
@media (max-width: 768px) {
  .header-content { flex-direction: column; gap: 12px; }
  .hero-section { min-height: 70vh; padding: 60px 20px; }
  .hero-actions { flex-direction: column; align-items: center; }
  .stats-grid { flex-direction: column; }
  .stat-item + .stat-item { border-left: none; border-top: 1px solid var(--border); }
  .section-title { font-size: 30px; }
  .sysreq-content { grid-template-columns: 1fr; }
  .steps-grid { grid-template-columns: 1fr 1fr; }
  .step-item + .step-item::before { display: none; }
  .download-info { grid-template-columns: 1fr; }
  .error-actions { flex-direction: column; align-items: center; }
  .compare-table { font-size: 13px; overflow-x: auto; }
  .detail-grid { grid-template-columns: 1fr; }
}

@media (max-width: 480px) {
  .steps-grid { grid-template-columns: 1fr; }
  .cta-content h2 { font-size: 30px; }
}