:root {
  --bg: #fdfcfc;
  --fg: #1e293b;
  --muted: #64748b;
  --accent: #246cff;
  --border-color: #eeeeee;
  --text-primary: var(--fg);
  --bg-card: #f8fafc;
  --welcome-max-width: 80rem;
  --welcome-side-padding: 1.5rem;
  --font-sans: 'Inter', system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --font-mono: 'JetBrains Mono', 'SF Mono', 'Fira Code', monospace;
  --radius-xs: 3px;
  --radius-sm: 5px;
  --radius-md: 6px;
  --radius-lg: 8px;
  --surface-card: var(--bg-card);
  --surface-muted: #fafafa;
  --border-soft: var(--border-color);
  --shadow-sm: 0 1px 2px rgb(0 0 0 / 5%);
  --accent-primary: #246cff;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #09090b;
    --fg: #f1f5f9;
    --muted: #94a3b8;
    --accent: #246cff;
    --border-color: #181818;
    --text-primary: var(--fg);
    --bg-card: #0f1214;
    --surface-muted: #1a1d23;
    --shadow-sm: 0 1px 2px rgb(0 0 0 / 20%);
  }
}

html.dark {
  --bg: #09090b;
  --fg: #f1f5f9;
  --muted: #94a3b8;
  --accent: #246cff;
  --border-color: #181818;
  --text-primary: var(--fg);
  --bg-card: #0f1214;
  --surface-muted: #1a1d23;
  --shadow-sm: 0 1px 2px rgb(0 0 0 / 20%);
}

html.light {
  --bg: #fdfcfc;
  --fg: #1e293b;
  --muted: #64748b;
  --accent: #246cff;
  --border-color: #eeeeee;
  --text-primary: var(--fg);
  --bg-card: #f8fafc;
  --surface-muted: #f1f5f9;
  --shadow-sm: 0 1px 2px rgb(0 0 0 / 5%);
}

html,
body {
  height: 100%;
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--fg);
  font-family: var(--font-sans);
}

* {
  transition:
    background-color 0.15s ease,
    border-color 0.15s ease,
    color 0.15s ease;
}

/* --- Scrollbar --- */
::-webkit-scrollbar {
  width: 4px;
  height: 4px;
}

::-webkit-scrollbar-track {
  background: transparent;
}

::-webkit-scrollbar-thumb {
  background: var(--border-color);
  border-radius: var(--radius-xs);
}

.hidden {
  display: none !important;
}

.header {
  position: fixed;
  top: 0;
  left: 50%;
  transform: translateX(-50%);
  width: 100%;
  max-width: var(--welcome-max-width);
  display: flex;
  justify-content: flex-end;
  align-items: center;
  gap: 0.5rem;
  padding: 0.75rem var(--welcome-side-padding);
  z-index: 10;
}

.wrap {
  width: 100%;
  max-width: var(--welcome-max-width);
  margin: 0 auto;
  min-height: 100%;
  display: grid;
  place-items: center;
  padding: 0 var(--welcome-side-padding);
}

.card {
  text-align: center;
  width: 100%;
}

.logo {
  height: 134px;
  margin: 0 auto 12px;
  display: block;
}

.subtitle {
  font-family: var(--font-sans);
  font-size: 0.875rem;
  font-weight: 400;
  color: var(--muted);
  letter-spacing: -0.01em;
  min-height: 20px;
  line-height: 1.5;
}

.subtitle.typewriter {
  position: relative;
  white-space: nowrap;
}

.subtitle.typewriter::after {
  content: '';
  display: inline-block;
  width: 2px;
  height: 1em;
  margin-left: 4px;
  background: currentColor;
  vertical-align: -0.15em;
  animation: caret-blink 1s steps(1, end) infinite;
}

@keyframes caret-blink {
  0%,
  49% {
    opacity: 1;
  }
  50%,
  100% {
    opacity: 0;
  }
}

@media (prefers-reduced-motion: reduce) {
  .subtitle.typewriter::after {
    animation: none;
  }
}

.actions {
  margin-top: 1.25rem;
  display: flex;
  gap: 0.5rem;
  justify-content: center;
  flex-wrap: wrap;
}

.os-btn {
  appearance: none;
  border: 1px solid var(--border-soft, var(--border-color));
  background: transparent;
  color: var(--text-primary);
  padding: 0.3rem 0.55rem;
  border-radius: var(--radius-sm);
  font-family: var(--font-sans);
  font-size: 0.75rem;
  font-weight: 500;
  text-decoration: none;
  transition:
    background-color 0.15s ease,
    border-color 0.15s ease;
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  cursor: pointer;
}

.os-btn:hover {
  background-color: var(--surface-muted, var(--bg-card));
}

.os-btn:focus-visible {
  outline: 2px solid color-mix(in srgb, var(--accent-primary) 15%, transparent);
  outline-offset: 1px;
}

.os-btn.primary {
  background: var(--accent-primary, #246cff);
  border-color: var(--accent-primary, #246cff);
  color: #fff;
}

html.dark .os-btn.primary {
  background: var(--accent-primary, #246cff);
  border-color: var(--accent-primary, #246cff);
}

.os-btn.primary:hover {
  filter: brightness(1.08);
}

.fade-enter-active,
.fade-leave-active {
  transition: opacity 0.5s ease;
}

.fade-enter-from,
.fade-leave-to {
  opacity: 0;
}

.dots {
  display: inline-block;
  width: 1em;
  text-align: left;
}

.dark-logo {
  display: block;
}

.light-logo {
  display: none;
}

html:not(.dark) .dark-logo {
  display: none;
}

.welcome-status {
  margin-top: 1rem;
  text-align: center;
  color: var(--muted);
  font-family: var(--font-sans);
  font-size: 0.75rem;
  max-width: 420px;
  line-height: 1.5;
}

@media (max-width: 640px) {
  :root {
    --welcome-side-padding: 1rem;
  }

  .header {
    justify-content: center;
    flex-wrap: wrap;
    gap: 0.35rem;
  }
}

html:not(.dark) .light-logo {
  display: block;
}

.theme-toggle {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 2rem;
  height: 2rem;
  border-radius: var(--radius-sm);
  background: transparent;
  border: 1px solid var(--border-soft, var(--border-color));
  color: var(--text-primary);
  cursor: pointer;
  transition: background-color 0.15s ease;
}

.theme-toggle:hover {
  background-color: var(--surface-muted, var(--bg-card));
}

.theme-toggle:focus-visible {
  outline: 2px solid color-mix(in srgb, var(--accent-primary, #246cff) 15%, transparent);
  outline-offset: 1px;
}

.theme-toggle svg {
  width: 1rem;
  height: 1rem;
  transition: opacity 0.15s ease;
}

.dark .theme-toggle .sun-icon {
  display: none;
}

.theme-toggle .moon-icon {
  display: none;
}

.dark .theme-toggle .moon-icon {
  display: block;
}

html:not(.dark) .theme-toggle .sun-icon {
  display: block;
}

.lang-select {
  background: transparent;
  color: var(--text-primary);
  border: 1px solid var(--border-soft, var(--border-color));
  border-radius: var(--radius-sm);
  padding: 0.3rem 0.5rem;
  font-family: var(--font-sans);
  font-size: 0.75rem;
  font-weight: 500;
}

.lang-select:hover,
.lang-select:focus {
  background-color: var(--surface-muted, var(--bg-card));
  outline: none;
}