/* ============================================================
   LAYOUT — header / nav / footer 骨架（全站）
   依赖 tokens.css + base.css
   ============================================================ */

/* ============ HEADER / NAV ============ */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  height: var(--header-height);
  background: rgba(12, 20, 139, 0.9);
  -webkit-backdrop-filter: blur(10px);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--border);
}

.nav-wrap {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: var(--header-height);
}

.logo {
  font-weight: var(--fw-bold);
  font-size: 26px;
  letter-spacing: 0.5px;
  color: var(--yellow);
}

.header-clock {
  font-size: 24px;
  color: var(--muted);
  font-family: "SF Mono", "Consolas", "Monaco", monospace;
  letter-spacing: 0.5px;
  margin-left: var(--space-5);
  margin-right: var(--space-5);
  padding: var(--space-1) var(--space-2) var(--space-1) var(--space-4);
  border-left: 1px solid var(--border);
  display: inline-block;
}

.site-nav {
  display: flex;
  gap: var(--space-5);
  align-items: center;
  margin-left: auto;
}

.site-nav a {
  color: var(--muted);
  font-size: 24px;
  transition: color 0.2s;
}

.site-nav a:hover {
  color: var(--text);
}

.nav-cta {
  color: var(--text) !important;
  border: 1px solid var(--border);
  padding: 6px 16px;
  line-height: 1.2;
  border-radius: var(--radius-btn);
  background: rgba(255, 255, 255, 0.06);
}

.nav-cta:hover {
  background: rgba(255, 255, 255, 0.15);
}

.nav-toggle,
.nav-toggle-label {
  display: none;
}

/* ============ NAV DROPDOWN ============ */
.nav-dropdown {
  position: relative;
}

.nav-dropdown-toggle {
  background: transparent;
  border: none;
  color: var(--muted);
  font-size: 24px;
  font-family: inherit;
  cursor: pointer;
  padding: 0;
  display: inline-flex;
  align-items: center;
  gap: 4px;
  transition: color 0.2s;
  line-height: inherit;
}

.nav-dropdown-toggle:hover {
  color: var(--text);
}

.nav-caret {
  font-size: 32px;
  vertical-align: middle;
  transition: transform 0.2s;
  display: inline-block;
}

.nav-dropdown-menu {
  position: absolute;
  top: 100%;
  left: 50%;
  transform: translateX(-50%) translateY(12px);
  min-width: 220px;
  background: var(--bg-alt);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: var(--space-2) 0;
  box-shadow: var(--shadow);
  opacity: 0;
  visibility: hidden;
  pointer-events: none;
  transition: opacity 0.2s, transform 0.2s, visibility 0.2s;
  z-index: 200;
}

.nav-dropdown-menu a {
  display: block;
  padding: 8px 20px;
  color: var(--text);
  font-size: 20px;
  transition: background 0.2s, color 0.2s;
  text-align: left;
  white-space: nowrap;
}

.nav-dropdown-menu a:hover {
  background: rgba(255, 255, 255, 0.06);
  color: var(--accent);
}

@media (hover: hover) and (pointer: fine) {
  .nav-dropdown:hover .nav-caret,
  .nav-dropdown:focus-within .nav-caret {
    transform: rotate(180deg);
  }

  .nav-dropdown:hover .nav-dropdown-menu,
  .nav-dropdown:focus-within .nav-dropdown-menu {
    opacity: 1;
    visibility: visible;
    pointer-events: auto;
    transform: translateX(-50%) translateY(4px);
  }
}

/* ============ LANGUAGE SWITCH ============ */
.lang-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  background: transparent;
  border: 1px solid var(--border);
  cursor: pointer;
  padding: var(--space-1) var(--space-2);
  border-radius: var(--radius-btn);
  margin-left: var(--space-4);
  transition: background 0.2s, border-color 0.2s;
  line-height: 1;
}

.lang-btn:hover {
  background: rgba(255, 255, 255, 0.06);
  border-color: var(--accent);
}

.lang-flag {
  font-size: 22px;
  line-height: 1;
  display: block;
}

/* ============ FOOTER ============ */
.site-footer {
  border-top: 1px solid var(--border);
  padding: var(--space-8) 0 var(--space-5);
  background: var(--bg-alt);
}

.footer-trust {
  text-align: center;
  padding-bottom: var(--space-6);
  margin-bottom: var(--space-6);
  border-bottom: 1px solid var(--border);
}

.footer-trust-label {
  font-size: var(--font-h4);
  text-transform: uppercase;
  letter-spacing: 1.5px;
  color: var(--muted);
  margin-bottom: var(--space-4);
}

.footer-trust-clients {
  font-size: var(--font-body);
  color: var(--text);
  font-weight: 500;
  line-height: 1.7;
}

.footer-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: var(--space-6);
  margin-bottom: var(--space-6);
  position: relative;
}

.footer-col {
  position: relative;
  text-align: center;
}

.footer-col h4 {
  font-size: var(--font-h4);
  text-transform: uppercase;
  letter-spacing: 1px;
  color: var(--accent);
  margin: 0;
  padding: var(--space-3) 0;
  cursor: pointer;
  transition: color 0.2s;
}

.footer-col h4:hover {
  color: var(--yellow);
}

.footer-col .submenu {
  position: absolute;
  bottom: 100%;
  left: 50%;
  transform: translateX(-50%) translateY(8px);
  min-width: 260px;
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: var(--space-4) var(--space-5);
  box-shadow: var(--shadow);
  opacity: 0;
  visibility: hidden;
  pointer-events: none;
  transition: opacity 0.2s, transform 0.2s, visibility 0.2s;
  z-index: 200;
}

.footer-col:hover .submenu {
  opacity: 1;
  visibility: visible;
  pointer-events: auto;
  transform: translateX(-50%) translateY(0);
}

.footer-col .submenu a {
  display: block;
  color: var(--text);
  font-size: var(--font-body);
  padding: var(--space-2) 0;
  opacity: 0.85;
  transition: opacity 0.2s, color 0.2s;
}

.footer-col .submenu a:hover {
  opacity: 1;
  color: var(--accent);
}

.footer-bottom {
  border-top: 1px solid var(--border);
  padding-top: var(--space-5);
  color: var(--muted);
  font-size: var(--font-body);
  text-align: center;
}

.footer-copyright {
  margin: 0;
  font-size: var(--font-body);
}

.footer-name {
  color: var(--yellow);
  font-weight: var(--fw-semibold);
}

/* ============ RESPONSIVE — header / nav / footer ============ */
@media (max-width: 900px) {
  .header-clock {
    display: none;
  }

  .footer-grid {
    grid-template-columns: repeat(2, 1fr);
    gap: var(--space-2) var(--space-4);
    margin-bottom: var(--space-5);
  }

  .footer-col {
    text-align: center;
    position: relative;
  }

  .footer-col h4 {
    font-size: var(--font-body);
    letter-spacing: 0.5px;
    padding: var(--space-3) var(--space-1);
  }

  .footer-col .submenu {
    position: absolute;
    bottom: 100%;
    top: auto;
    left: 50%;
    transform: translateX(-50%) translateY(8px);
    min-width: 240px;
    padding: var(--space-3) var(--space-4);
    opacity: 0;
    visibility: hidden;
    pointer-events: none;
  }

  .footer-col.open .submenu {
    opacity: 1;
    visibility: visible;
    pointer-events: auto;
    transform: translateX(-50%) translateY(0);
  }

  .footer-col:hover .submenu {
    opacity: 0;
    visibility: hidden;
    pointer-events: none;
  }

  .footer-col.open:hover .submenu {
    opacity: 1;
    visibility: visible;
    pointer-events: auto;
  }

  .footer-col .submenu a {
    font-size: var(--font-body);
    padding: var(--space-1) 0;
  }

  /* NAV DROPDOWN (tablet) */
  .nav-dropdown {
    width: 100%;
  }

  .nav-dropdown-toggle {
    display: none;
  }

  .nav-dropdown-menu {
    position: static;
    opacity: 1;
    visibility: visible;
    pointer-events: auto;
    transform: none;
    background: transparent;
    border: none;
    box-shadow: none;
    padding: 0;
    min-width: 0;
  }

  .nav-dropdown-menu a {
    padding: var(--space-3) var(--space-5);
    border-bottom: 1px solid var(--border);
    width: 100%;
    text-align: right;
    font-size: var(--font-body);
    color: var(--muted);
    white-space: normal;
  }
}

@media (max-width: 900px) and (min-width: 641px) {
  .nav-wrap {
    display: flex;
    align-items: center;
  }

  .nav-toggle-label {
    display: block;
    cursor: pointer;
    padding: var(--space-2);
    order: 2;
    margin-left: var(--space-3);
  }

  .nav-toggle-label span,
  .nav-toggle-label span::before,
  .nav-toggle-label span::after {
    display: block;
    background-color: var(--text) !important;
    height: 2px;
    width: 30px;
    position: relative;
    transition: 0.3s;
  }

  .nav-toggle-label span::before,
  .nav-toggle-label span::after {
    content: "";
    position: absolute;
  }

  .nav-toggle-label span::before {
    top: -10px;
  }

  .nav-toggle-label span::after {
    top: 10px;
  }

  .lang-btn {
    order: 1;
    margin-left: auto;
    margin-right: 0;
  }

  .site-nav {
    order: 3;
    position: fixed;
    top: var(--header-height);
    right: 0;
    left: auto;
    width: auto;
    min-width: 240px;
    background: var(--bg-alt);
    border-left: 1px solid var(--border);
    border-bottom: 1px solid var(--border);
    border-radius: 0 0 0 var(--radius);
    flex-direction: column;
    align-items: flex-end;
    gap: 0;
    padding: 0;
    margin-left: 0;
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.3s;
  }

  .site-nav a {
    padding: var(--space-3) var(--space-5);
    border-bottom: 1px solid var(--border);
    width: 100%;
    text-align: right;
    font-size: var(--font-body);
  }

  .nav-toggle:checked~.site-nav {
    max-height: calc(100vh - var(--header-height) - 64px);
    overflow-y: auto;
    -webkit-overflow-scrolling: touch;
  }
}

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

  .nav-wrap {
    display: flex;
    align-items: center;
  }

  .logo {
    order: 1;
  }

  .lang-btn {
    order: 2;
    margin-left: auto;
    margin-right: var(--space-2);
  }

  .nav-toggle-label {
    order: 3;
    display: block;
    cursor: pointer;
    padding: var(--space-2);
  }

  .nav-toggle-label span,
  .nav-toggle-label span::before,
  .nav-toggle-label span::after {
    display: block;
    background-color: var(--text) !important;
    height: 2px;
    width: 30px;
    position: relative;
    transition: 0.3s;
  }

  .nav-toggle-label span::before,
  .nav-toggle-label span::after {
    content: "";
    position: absolute;
  }

  .nav-toggle-label span::before {
    top: -10px;
  }

  .nav-toggle-label span::after {
    top: 10px;
  }

  .site-nav {
    order: 4;
    position: fixed;
    top: var(--header-height);
    right: 0;
    left: auto;
    width: auto;
    min-width: 240px;
    background: var(--bg-alt);
    border-left: 1px solid var(--border);
    border-bottom: 1px solid var(--border);
    border-radius: 0 0 0 var(--radius);
    flex-direction: column;
    align-items: flex-end;
    gap: 0;
    padding: 0;
    margin-left: 0;
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.3s;
  }

  .site-nav a {
    padding: var(--space-3) var(--space-5);
    border-bottom: 1px solid var(--border);
    width: 100%;
    text-align: right;
    font-size: var(--font-body);
  }

  .nav-toggle:checked~.site-nav {
    max-height: calc(100vh - var(--header-height) - 64px);
    overflow-y: auto;
    -webkit-overflow-scrolling: touch;
  }

  .footer-bottom {
    flex-direction: column;
    text-align: center;
    gap: var(--space-2);
  }
}