/**
 * header.php — .site-header 及导航、移动端按钮
 * 依赖 typography-system.css 中的字号与字体变量。
 */

.site-header {
  position: relative;
  z-index: 20;
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--color-border, rgba(26, 26, 46, 0.07));
  transition: box-shadow 0.3s;
}

.site-header--scrolled {
  box-shadow: 0 1px 20px rgba(0, 0, 0, 0.06);
}

.site-header .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
}

.site-header__logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-family: var(--font-display, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Arial, sans-serif);
  font-size: var(--text-xl, 20px);
  font-weight: 700;
  color: var(--color-text, #1a1a2e);
  letter-spacing: 0.01em;
}

.site-header__logo-mark {
  width: 34px;
  height: 34px;
  background: var(--color-deep, #091b2a);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--color-accent, #b48a3c);
  font-family: var(--font-display, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Arial, sans-serif);
  font-size: var(--text-md, 16px);
  font-weight: 700;
}

.site-header__nav {
  display: none;
  gap: 28px;
}

.site-header__nav a {
  font-size: var(--text-sm, 13px);
  font-weight: 500;
  color: var(--color-text-muted, #5a6277);
  letter-spacing: 0.03em;
  transition: color 0.2s;
}

.site-header__nav a:hover,
.site-header__nav a.is-active {
  color: var(--color-text, #1a1a2e);
}

.site-header__actions {
  display: none;
  gap: 12px;
}

.mobile-menu-btn {
  display: flex;
  flex-direction: column;
  gap: 4px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 6px;
}

.mobile-menu-btn span {
  width: 20px;
  height: 1.5px;
  background: var(--color-text, #1a1a2e);
}

@media (min-width: 1024px) {
  .site-header__nav {
    display: flex;
  }

  .site-header__actions {
    display: flex;
  }

  .mobile-menu-btn {
    display: none;
  }
}