:root {
  --ui-surface: rgba(15, 23, 42, 0.76);
  --ui-border: rgba(148, 163, 184, 0.24);
  --ui-text: #e2e8f0;
  --ui-muted: #a1b0c7;
  --ui-accent: #38bdf8;
  --ui-bg: #070d18;
  --ui-bg-soft: #111a2e;
}

html[data-theme="light"] {
  --ui-surface: rgba(255, 255, 255, 0.82);
  --ui-border: rgba(100, 116, 139, 0.25);
  --ui-text: #152235;
  --ui-muted: #435975;
  --ui-accent: #0284c7;
  --ui-bg: #edf3fc;
  --ui-bg-soft: #dce8f8;
}

.topbar {
  position: sticky;
  top: 0;
  z-index: 40;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding: 1rem clamp(1rem, 4vw, 3rem);
  backdrop-filter: blur(10px);
  background: color-mix(in srgb, var(--ui-bg) 74%, transparent);
  border-bottom: 1px solid color-mix(in srgb, var(--ui-border) 80%, transparent);
}

.brand {
  text-decoration: none;
  color: var(--ui-text);
  font-weight: 700;
  letter-spacing: 0.03em;
}

.nav {
  display: flex;
  align-items: center;
  gap: 0.45rem;
}

.icon-btn,
.nav-link,
.option,
.toggle-btn {
  border: 1px solid transparent;
  border-radius: 999px;
  color: var(--ui-text);
  text-decoration: none;
  background: transparent;
  padding: 0.5rem 0.88rem;
  font: inherit;
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  gap: 0.42rem;
  transition: transform 170ms ease, border-color 170ms ease, background-color 170ms ease;
}

.icon-btn svg,
.nav-link svg {
  width: 1rem;
  height: 1rem;
}

.icon-btn:hover,
.nav-link:hover,
.option:hover,
.toggle-btn:hover {
  transform: translateY(-1px);
  background: color-mix(in srgb, var(--ui-accent) 14%, transparent);
  border-color: color-mix(in srgb, var(--ui-border) 86%, transparent);
}

.menu-toggle {
  display: none;
}

.settings {
  position: fixed;
  top: 0;
  right: 0;
  z-index: 55;
  width: min(390px, 100%);
  height: 100%;
  padding: 1rem;
  display: grid;
  align-content: start;
  gap: 0.8rem;
  border-left: 1px solid var(--ui-border);
  background: color-mix(in srgb, var(--ui-bg) 82%, transparent);
  backdrop-filter: blur(18px);
  transform: translateX(104%);
  transition: transform 220ms ease;
}

.settings.open {
  transform: translateX(0);
}

.settings-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.settings-group {
  border: 1px solid color-mix(in srgb, var(--ui-border) 84%, transparent);
  border-radius: 14px;
  padding: 0.8rem;
  background: color-mix(in srgb, var(--ui-surface) 90%, transparent);
}

.settings-label {
  margin: 0 0 0.5rem;
  color: var(--ui-muted);
  font-size: 0.92rem;
}

.switch-row {
  display: flex;
  flex-wrap: wrap;
  gap: 0.45rem;
}

.option.active {
  border-color: color-mix(in srgb, var(--ui-accent) 65%, transparent);
  background: color-mix(in srgb, var(--ui-accent) 18%, transparent);
}

.toggle {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 0.7rem;
}

.toggle input[type="checkbox"] {
  width: 42px;
  height: 22px;
  accent-color: var(--ui-accent);
}

.backdrop {
  position: fixed;
  inset: 0;
  z-index: 50;
  background: rgba(2, 6, 23, 0.58);
}

@media (max-width: 760px) {
  .topbar {
    flex-wrap: wrap;
  }

  .menu-toggle {
    display: inline-flex;
  }

  .nav {
    display: none;
    width: 100%;
    flex-wrap: wrap;
    justify-content: flex-start;
  }

  .nav.open {
    display: flex;
  }
}