/*
 * 版本: 1.0.1
 * 时间: 2025-10-15 13:00
 * 作者: Aden
 * 识别码: f2c91a3e7d
 * 严重声明：禁止盗用代码，否则追查到底。
 */

:root {
  --transition-duration: 0.3s;
  /* 默认使用亮色变量，暗黑模式再覆盖差异 */
  --bg-body: #f8faff;
  --text-primary: #1a1d2d;
  --text-secondary: rgba(58, 66, 90, 0.72);
  --section-label: rgba(58, 66, 90, 0.55);
  --navbar-bg: rgba(255, 255, 255, 0.85);
  --navbar-bg-mobile: rgba(255, 255, 255, 0.95);
  --navbar-bg-scrolled: rgba(255, 255, 255, 0.98);
  --navbar-link: rgba(37, 43, 69, 0.75);
  --navbar-link-active: #101426;
  --navbar-shadow: none;
  --navbar-shadow-scrolled: 0 18px 38px rgba(22, 26, 55, 0.12);
  --navbar-toggler-border: rgba(31, 36, 60, 0.18);
  --navbar-toggler-border-hover: rgba(26, 31, 54, 0.42);
  --navbar-toggler-bg: rgba(240, 243, 255, 0.92);
  --navbar-toggler-bg-hover: rgba(232, 236, 253, 0.98);
  --navbar-toggler-icon: rgba(43, 49, 75, 0.82);
  --navbar-toggler-icon-hover: rgba(24, 29, 55, 0.92);
  --navbar-toggler-shadow: none;
  --navbar-toggler-focus-ring: rgba(26, 31, 54, 0.12);
  --hero-gradient-1: rgba(116, 185, 255, 0.25);
  --hero-gradient-2: rgba(108, 92, 231, 0.18);
  --hero-badge-bg: rgba(37, 43, 69, 0.07);
  --hero-badge-text: #2d3352;
  --card-bg: rgba(255, 255, 255, 0.94);
  --card-border: rgba(37, 43, 69, 0.08);
  --card-border-hover: rgba(108, 92, 231, 0.35);
  --card-shadow: 0 18px 45px rgba(18, 22, 54, 0.08);
  --device-shell-gradient: linear-gradient(160deg, rgba(116, 185, 255, 0.32), rgba(108, 92, 231, 0.18));
  --device-screen-bg: rgba(250, 252, 255, 0.98);
  --device-screen-border: rgba(37, 43, 69, 0.05);
  --device-signal-color: #1a8cff;
  --section-alt-bg-top: rgba(242, 245, 255, 0.9);
  --section-alt-bg-bottom: rgba(237, 240, 255, 0.95);
  --airport-hero-gradient-left: rgba(108, 92, 231, 0.18);
  --airport-hero-gradient-right: rgba(77, 205, 170, 0.22);
  --footer-bg: rgba(255, 255, 255, 0.92);
  --border-subtle: rgba(28, 31, 51, 0.12);
  --tag-bg: rgba(108, 92, 231, 0.12);
  --tag-text: rgba(55, 30, 156, 0.8);
  --btn-outline-color: rgba(26, 29, 45, 0.85);
  --btn-outline-hover-bg: #1a1d2d;
  --btn-outline-hover-text: #ffffff;
  --toggle-border: rgba(26, 29, 45, 0.3);
  --toggle-color: #1a1d2d;
  --toggle-hover-bg: rgba(26, 29, 45, 0.06);
  --toggle-hover-text: #1a1d2d;
  --preview-shadow: 0 26px 60px rgba(32, 40, 80, 0.12);
  --preview-shadow-hover: 0 30px 80px rgba(32, 40, 80, 0.16);
}

/* === Base Layout === */

body {
  font-family: "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  background: var(--bg-body);
  color: var(--text-primary);
  transition: background-color var(--transition-duration) ease,
    color var(--transition-duration) ease;
}

body.theme-dark {
  --bg-body: #0f1116;
  --text-primary: #f5f7fb;
  --text-secondary: rgba(229, 236, 255, 0.65);
  --section-label: rgba(255, 255, 255, 0.55);
  --navbar-bg: rgba(15, 17, 22, 0.75);
  --navbar-bg-mobile: rgba(15, 17, 22, 0.95);
  --navbar-bg-scrolled: rgba(15, 17, 22, 0.95);
  --navbar-link: rgba(255, 255, 255, 0.75);
  --navbar-link-active: #f5f7fb;
  --navbar-shadow: none;
  --navbar-shadow-scrolled: 0 12px 45px rgba(10, 12, 18, 0.45);
  --navbar-toggler-border: rgba(135, 175, 225, 0.7);
  --navbar-toggler-border-hover: rgba(190, 226, 255, 0.92);
  --navbar-toggler-bg: rgba(68, 110, 195, 0.34);
  --navbar-toggler-bg-hover: rgba(82, 134, 230, 0.42);
  --navbar-toggler-icon: rgba(241, 247, 255, 0.97);
  --navbar-toggler-icon-hover: #ffffff;
  --navbar-toggler-shadow: 0 8px 24px rgba(15, 34, 72, 0.28);
  --navbar-toggler-focus-ring: rgba(255, 255, 255, 0.12);
  --hero-gradient-1: rgba(116, 185, 255, 0.3);
  --hero-gradient-2: rgba(108, 92, 231, 0.2);
  --hero-badge-bg: rgba(255, 255, 255, 0.08);
  --hero-badge-text: #e5ecff;
  --card-bg: rgba(20, 24, 34, 0.85);
  --card-border: rgba(255, 255, 255, 0.03);
  --card-border-hover: rgba(116, 185, 255, 0.45);
  --card-shadow: 0 18px 45px rgba(6, 8, 12, 0.4);
  --device-shell-gradient: linear-gradient(160deg, rgba(116, 185, 255, 0.18), rgba(108, 92, 231, 0.12));
  --device-screen-bg: rgba(12, 16, 26, 0.96);
  --device-screen-border: rgba(255, 255, 255, 0.02);
  --device-signal-color: #74b9ff;
  --section-alt-bg-top: rgba(16, 18, 24, 0.95);
  --section-alt-bg-bottom: rgba(9, 11, 16, 0.98);
  --airport-hero-gradient-left: rgba(108, 92, 231, 0.25);
  --airport-hero-gradient-right: rgba(0, 184, 148, 0.25);
  --footer-bg: rgba(12, 14, 20, 0.85);
  --border-subtle: rgba(255, 255, 255, 0.08);
  --tag-bg: rgba(116, 185, 255, 0.18);
  --tag-text: #dfe6ff;
  --btn-outline-color: rgba(245, 247, 251, 0.8);
  --btn-outline-hover-bg: rgba(245, 247, 251, 0.15);
  --btn-outline-hover-text: #fdfdff;
  --toggle-border: rgba(245, 247, 251, 0.35);
  --toggle-color: #f5f7fb;
  --toggle-hover-bg: rgba(245, 247, 251, 0.1);
  --toggle-hover-text: #ffffff;
  --preview-shadow: 0 28px 70px rgba(7, 12, 25, 0.6);
  --preview-shadow-hover: 0 32px 90px rgba(7, 12, 25, 0.7);
  color-scheme: dark;
}

body.theme-light {
  color-scheme: light;
}

/* === Navigation === */

.navbar {
  background: var(--navbar-bg);
  backdrop-filter: blur(18px);
  transition: background-color var(--transition-duration) ease, box-shadow var(--transition-duration) ease;
  box-shadow: var(--navbar-shadow);
}

.navbar.navbar-scrolled {
  background: var(--navbar-bg-scrolled);
  box-shadow: var(--navbar-shadow-scrolled);
}

.navbar .nav-link {
  font-weight: 500;
  color: var(--navbar-link);
  transition: color var(--transition-duration) ease;
}

.navbar .nav-link:hover,
.navbar .nav-link.active {
  color: var(--navbar-link-active);
}

.navbar .navbar-brand {
  color: var(--navbar-link-active);
  transition: color var(--transition-duration) ease;
}

.brand-logo {
  width: 38px;
  height: 38px;
  border-radius: 12px;
  object-fit: cover;
}

.navbar .navbar-brand:hover,
.navbar .navbar-brand:focus {
  color: var(--navbar-link-active);
}

.navbar-toggler {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.45rem;
  width: 44px;
  height: 40px;
  border-radius: 12px;
  border-color: var(--navbar-toggler-border);
  background-color: var(--navbar-toggler-bg);
  box-shadow: var(--navbar-toggler-shadow);
  transition: border-color var(--transition-duration) ease, background-color var(--transition-duration) ease,
    box-shadow var(--transition-duration) ease, transform var(--transition-duration) ease;
}

.navbar-toggler:hover,
.navbar-toggler:focus,
.navbar-toggler:focus-visible {
  border-color: var(--navbar-toggler-border-hover);
  background-color: var(--navbar-toggler-bg-hover);
  box-shadow: 0 0 0 2px var(--navbar-toggler-focus-ring);
  outline: none;
  transform: translateY(-1px);
}

.navbar-toggler-icon {
  width: 22px;
  height: 16px;
  color: var(--navbar-toggler-icon);
  transition: color var(--transition-duration) ease;
}

.navbar-toggler-icon line {
  stroke: currentColor;
  stroke-width: 2.2;
  stroke-linecap: round;
}

.navbar-toggler:hover .navbar-toggler-icon,
.navbar-toggler:focus .navbar-toggler-icon,
.navbar-toggler:focus-visible .navbar-toggler-icon {
  color: var(--navbar-toggler-icon-hover);
}

.logo-shape {
  width: 38px;
  height: 38px;
  border-radius: 12px;
  background: linear-gradient(135deg, #6c5ce7, #74b9ff);
  box-shadow: 0 10px 25px rgba(116, 185, 255, 0.45);
}

/* === Hero Sections === */
.hero-section,
.hero-airport,
.hero-guide {
  position: relative;
  padding-top: 6rem;
  padding-bottom: 6rem;
  transition: background var(--transition-duration) ease;
}

.hero-section {
  background: radial-gradient(circle at top left, var(--hero-gradient-1), transparent 50%),
    radial-gradient(circle at bottom right, var(--hero-gradient-2), transparent 55%);
}

.hero-section .lead {
  max-width: 540px;
}

.hero-badge {
  background: var(--hero-badge-bg);
  border-radius: 999px;
  padding: 0.45rem 1rem;
  font-size: 0.95rem;
  color: var(--hero-badge-text);
  letter-spacing: 0.02em;
  transition: background-color var(--transition-duration) ease, color var(--transition-duration) ease;
}

/* === Section Utilities === */

.bg-gradient-dark {
  background: linear-gradient(180deg, var(--section-alt-bg-top) 0%, var(--section-alt-bg-bottom) 100%);
  transition: background var(--transition-duration) ease;
}

.section-label {
  text-transform: uppercase;
  font-size: 0.9rem;
  letter-spacing: 0.14em;
  color: var(--section-label);
  transition: color var(--transition-duration) ease;
}

/* === Card Surfaces === */

.surface-card,
.feature-card,
.download-card,
.airport-card,
.airport-highlight,
.community-card {
  background: var(--card-bg);
  border-radius: 20px;
  padding: 1.75rem;
  border: 1px solid var(--card-border);
  box-shadow: var(--card-shadow);
  transition: transform 0.25s ease, border-color var(--transition-duration) ease, background-color var(--transition-duration) ease,
    box-shadow var(--transition-duration) ease;
}

.feature-card:hover,
.download-card:hover,
.airport-card:hover,
.community-card:hover {
  transform: translateY(-6px);
  border-color: var(--card-border-hover);
}

.feature-icon {
  width: 52px;
  height: 52px;
  border-radius: 14px;
  background: linear-gradient(135deg, rgba(116, 185, 255, 0.8), rgba(108, 92, 231, 0.8));
  display: grid;
  place-items: center;
  margin-bottom: 1.25rem;
  font-size: 1.5rem;
  color: #fff;
}

.download-card {
  border-radius: 20px;
}

.download-icon {
  display: grid;
  place-items: center;
  width: 44px;
  height: 44px;
  border-radius: 14px;
  background: linear-gradient(135deg, #74b9ff, #6c5ce7);
}

.download-icon.ios {
  background: linear-gradient(135deg, #dfe6e9, #636e72);
}

.download-icon.mac {
  background: linear-gradient(135deg, #636e72, #2d3436);
}

.download-icon.tvos {
  background: linear-gradient(135deg, #4b7bec, #a55eea);
}

.download-icon-label {
  display: inline-block;
  padding: 0 0.25rem;
  font-size: 0.65rem;
  font-weight: 600;
  letter-spacing: 0.01em;
  line-height: 1;
  color: #ffffff;
}

.hero-airport {
  background: radial-gradient(circle at left, var(--airport-hero-gradient-left), transparent 55%),
    radial-gradient(circle at right, var(--airport-hero-gradient-right), transparent 60%);
}

.airport-card .btn {
  margin-top: auto;
}

.airport-tag {
  display: inline-flex;
  align-items: center;
  padding: 0.35rem 0.85rem;
  border-radius: 999px;
  font-size: 0.75rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  background: var(--tag-bg);
  color: var(--tag-text);
  transition: background-color var(--transition-duration) ease, color var(--transition-duration) ease;
}

.hero-guide {
  background: radial-gradient(circle at 10% 15%, var(--hero-gradient-1), transparent 55%),
    radial-gradient(circle at 80% 90%, var(--airport-hero-gradient-right), transparent 60%);
}

.app-preview,
.guide-illustration {
  background: transparent;
  border: none;
  border-radius: 32px;
  padding: 0;
  overflow: hidden;
  box-shadow: var(--preview-shadow);
  transition: box-shadow var(--transition-duration) ease, transform 0.3s ease;
}

.app-preview:hover,
.guide-illustration:hover {
  transform: translateY(-4px);
  box-shadow: var(--preview-shadow-hover);
}

.hero-banner {
  display: block;
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: center;
}

.guide-steps {
  display: grid;
  gap: 1rem;
}

.guide-step {
  display: flex;
  gap: 1.25rem;
  padding: 1.25rem 1.5rem;
  border: 1px solid var(--card-border);
  border-radius: 18px;
  background: rgba(255, 255, 255, 0.02);
  transition: background-color var(--transition-duration) ease, border-color var(--transition-duration) ease;
}

body.theme-light .guide-step {
  background: rgba(255, 255, 255, 0.85);
}

.guide-step:hover {
  border-color: var(--card-border-hover);
}

.step-number {
  flex-shrink: 0;
  width: 48px;
  height: 48px;
  border-radius: 16px;
  display: grid;
  place-items: center;
  font-weight: 600;
  font-size: 0.95rem;
  letter-spacing: 0.06em;
  color: #fff;
  background: linear-gradient(135deg, #6c5ce7, #74b9ff);
  box-shadow: 0 12px 24px rgba(116, 185, 255, 0.25);
}

.community-card {
  padding: 1.9rem 1.75rem;
  text-align: left;
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.community-card p {
  flex-grow: 1;
}

.community-icon {
  width: 52px;
  height: 52px;
  border-radius: 16px;
  display: grid;
  place-items: center;
  font-size: 1.7rem;
  color: #fff;
  box-shadow: 0 16px 32px rgba(0, 0, 0, 0.25);
}

.community-icon.bg-telegram {
  background: linear-gradient(135deg, #1f8ef1, #55c6f7);
}

.community-icon.bg-x {
  background: linear-gradient(135deg, #0f172a, #1f2937);
}

.community-icon.bg-discord {
  background: linear-gradient(135deg, #5865f2, #8c9bff);
}

.community-icon.bg-qq {
  background: linear-gradient(135deg, #00a9f0, #0072ff);
}

.community-icon.bg-forum {
  background: linear-gradient(135deg, #0abde3, #10ac84);
}

footer {
  background: var(--footer-bg);
  transition: background-color var(--transition-duration) ease;
}

body .text-secondary {
  color: var(--text-secondary) !important;
}

body.theme-dark h1,
body.theme-dark h2,
body.theme-dark .h1,
body.theme-dark .h2,
body.theme-dark .h3,
body.theme-dark .h4 {
  color: var(--text-primary);
}

body .border-secondary-subtle {
  border-color: var(--border-subtle) !important;
}

body .btn-outline-light {
  color: var(--btn-outline-color);
  border-color: var(--btn-outline-color);
  transition: background-color var(--transition-duration) ease, color var(--transition-duration) ease,
    border-color var(--transition-duration) ease, box-shadow var(--transition-duration) ease;
}

body .btn-outline-light:hover,
body .btn-outline-light:focus-visible {
  background: var(--btn-outline-hover-bg);
  color: var(--btn-outline-hover-text);
  border-color: var(--btn-outline-hover-text);
}

.theme-toggle {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.45rem;
  width: 100%;
  padding: 0.45rem 1rem;
  border-radius: 999px;
  border: 1px solid var(--toggle-border);
  color: var(--toggle-color);
  background: transparent;
  transition: background-color var(--transition-duration) ease, color var(--transition-duration) ease,
    border-color var(--transition-duration) ease;
}

.theme-toggle:hover,
.theme-toggle:focus-visible {
  background: var(--toggle-hover-bg);
  color: var(--toggle-hover-text);
  border-color: var(--toggle-color);
  outline: none;
}

.theme-toggle .bi {
  font-size: 1.1rem;
}

@media (max-width: 991.98px) {
  .navbar {
    background: var(--navbar-bg-mobile);
  }

  .hero-section,
  .hero-airport,
  .hero-guide {
    padding-top: 4.5rem;
    padding-bottom: 4.5rem;
  }
}

@media (max-width: 575.98px) {
  .hero-section h1 {
    font-size: 2.2rem;
  }

  .display-6 {
    font-size: 2rem;
  }

  .guide-step {
    flex-direction: column;
  }
}

@media (min-width: 992px) {
  .py-lg-6 {
    padding-top: 6rem !important;
    padding-bottom: 6rem !important;
  }

  .theme-toggle {
    width: auto;
  }
}