/* ==========================================================================
   base.css — design tokens, resets, typography, accessibility primitives
   ========================================================================== */

:root {
  /* Brand / accent */
  --accent: #5b8cff;
  --accent-strong: #3a5fd9;
  --accent-soft: rgba(91, 140, 255, 0.18);

  /* Surfaces (dark theme, default) */
  --bg-0: #0a0d14;
  --bg-1: #0e121b;
  --surface-1: rgba(255, 255, 255, 0.06);
  --surface-2: rgba(255, 255, 255, 0.09);
  --surface-3: rgba(255, 255, 255, 0.14);
  --border-1: rgba(255, 255, 255, 0.10);
  --border-2: rgba(255, 255, 255, 0.16);

  --text-0: rgba(255, 255, 255, 0.96);
  --text-1: rgba(255, 255, 255, 0.78);
  --text-2: rgba(255, 255, 255, 0.52);
  --text-on-accent: #ffffff;

  /* Glass */
  --glass-bg: rgba(20, 24, 34, 0.55);
  --glass-bg-strong: rgba(16, 19, 28, 0.72);
  --glass-blur: 22px;
  --glass-border: rgba(255, 255, 255, 0.12);

  /* Radii */
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 16px;
  --radius-xl: 22px;
  --radius-pill: 999px;

  /* Shadows */
  --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.25);
  --shadow-md: 0 8px 24px rgba(0, 0, 0, 0.35);
  --shadow-lg: 0 24px 64px rgba(0, 0, 0, 0.45);
  --shadow-window: 0 30px 70px rgba(0, 0, 0, 0.5), 0 4px 16px rgba(0, 0, 0, 0.3);
  --shadow-window-active: 0 40px 90px rgba(0, 0, 0, 0.55), 0 6px 20px rgba(0, 0, 0, 0.35);

  /* Layout */
  --menubar-h: 36px;
  --taskbar-h: 56px;
  --dock-w: 76px;

  /* Motion */
  --ease-out-back: cubic-bezier(0.34, 1.56, 0.64, 1);
  --ease-out: cubic-bezier(0.16, 1, 0.3, 1);
  --ease-in-out: cubic-bezier(0.45, 0, 0.2, 1);
  --motion-scale: 1; /* multiplied into durations via Settings → Animation speed */
  --dur-fast-base: 150ms;
  --dur-med-base: 320ms;
  --dur-window-base: 600ms;
  --dur-exit-base: 700ms;
  --dur-fast: calc(var(--dur-fast-base) * var(--motion-scale));
  --dur-med: calc(var(--dur-med-base) * var(--motion-scale));
  --dur-window: calc(var(--dur-window-base) * var(--motion-scale));
  --dur-exit: calc(var(--dur-exit-base) * var(--motion-scale));

  /* Z-index layers */
  --z-wallpaper: 0;
  --z-desktop: 10;
  --z-window-base: 100;
  --z-dock: 4000;
  --z-taskbar: 4000;
  --z-menubar: 4500;
  --z-startmenu: 5000;
  --z-search: 5100;
  --z-snap-preview: 3000;
  --z-toast: 6000;

  /* Transparency (user adjustable via Settings) */
  --ui-opacity: 1;

  font-size: 15px;
}

/* Light theme overrides */
:root[data-theme="light"] {
  --bg-0: #eef1f6;
  --bg-1: #e6e9f0;
  --surface-1: rgba(20, 24, 34, 0.05);
  --surface-2: rgba(20, 24, 34, 0.08);
  --surface-3: rgba(20, 24, 34, 0.13);
  --border-1: rgba(20, 24, 34, 0.08);
  --border-2: rgba(20, 24, 34, 0.14);

  --text-0: rgba(15, 18, 25, 0.94);
  --text-1: rgba(15, 18, 25, 0.72);
  --text-2: rgba(15, 18, 25, 0.48);

  --glass-bg: rgba(255, 255, 255, 0.6);
  --glass-bg-strong: rgba(255, 255, 255, 0.78);
  --glass-border: rgba(15, 18, 25, 0.10);

  --shadow-window: 0 24px 60px rgba(20, 24, 34, 0.18), 0 4px 14px rgba(20, 24, 34, 0.12);
  --shadow-window-active: 0 32px 70px rgba(20, 24, 34, 0.22), 0 6px 18px rgba(20, 24, 34, 0.14);
}

* {
  box-sizing: border-box;
}

html, body {
  margin: 0;
  padding: 0;
  width: 100%;
  height: 100%;
  overflow: hidden;
  background: var(--bg-0);
  color: var(--text-0);
  font-family: "Segoe UI Variable", "Segoe UI", -apple-system, BlinkMacSystemFont, "SF Pro Text", "Inter", Roboto, Helvetica, Arial, sans-serif;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  user-select: none;
}

button {
  font-family: inherit;
  color: inherit;
}

img, svg {
  display: block;
}

input, select, button, textarea {
  font-family: inherit;
}

::-webkit-scrollbar {
  width: 10px;
  height: 10px;
}
::-webkit-scrollbar-thumb {
  background: var(--surface-3);
  border-radius: var(--radius-pill);
}
::-webkit-scrollbar-track {
  background: transparent;
}

a {
  color: var(--accent);
  text-decoration: none;
}
a:hover {
  text-decoration: underline;
}

/* Accessible focus ring everywhere, only shown for keyboard users */
:focus {
  outline: none;
}
.a11y-focus:focus-visible,
button:focus-visible,
a:focus-visible,
[tabindex]:focus-visible,
input:focus-visible,
select:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
  border-radius: var(--radius-sm);
}

.visually-hidden {
  position: absolute !important;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

.glass {
  background: var(--glass-bg);
  backdrop-filter: blur(var(--glass-blur)) saturate(1.4);
  -webkit-backdrop-filter: blur(var(--glass-blur)) saturate(1.4);
  border: 1px solid var(--glass-border);
}

.glass-strong {
  background: var(--glass-bg-strong);
  backdrop-filter: blur(calc(var(--glass-blur) + 6px)) saturate(1.5);
  -webkit-backdrop-filter: blur(calc(var(--glass-blur) + 6px)) saturate(1.5);
  border: 1px solid var(--glass-border);
}

/* Reduced motion: user OS preference */
@media (prefers-reduced-motion: reduce) {
  :root {
    --dur-fast: 1ms;
    --dur-med: 1ms;
    --dur-window: 1ms;
    --dur-exit: 1ms;
  }
}

/* Reduced motion: explicit app setting */
:root[data-reduce-motion="true"] {
  --dur-fast: 1ms;
  --dur-med: 1ms;
  --dur-window: 1ms;
  --dur-exit: 1ms;
}

:root[data-transparency="off"] {
  --glass-bg: var(--glass-bg-strong);
  --glass-blur: 0px;
}