@tailwind base;
@tailwind components;
@tailwind utilities;

@layer base {
  :root {
    /* 3blue1brown-inspired dark palette: deep space blue background,
       a warm gold accent for emphasis, and a small, deliberate set of
       "state" colors used consistently across every visualization. */
    --background: 222 47% 7%;
    --foreground: 210 40% 96%;

    --primary: 199 89% 64%;          /* 3b1b sky blue */
    --primary-foreground: 222 47% 7%;
    --secondary: 222 30% 16%;
    --secondary-foreground: 210 40% 90%;
    --accent: 43 96% 62%;            /* warm gold, used sparingly */
    --accent-foreground: 222 47% 7%;
    --destructive: 358 75% 59%;
    --destructive-foreground: 210 40% 96%;
    --muted: 222 25% 14%;
    --muted-foreground: 215 20% 65%;
    --card: 222 40% 10%;
    --card-foreground: 210 40% 96%;
    --popover: 222 44% 9%;
    --popover-foreground: 210 40% 96%;
    --border: 222 25% 20%;
    --input: 222 25% 20%;
    --ring: 199 89% 64%;
    --radius: 0.75rem;

    /* Algorithm state colors — one meaning each, used everywhere. */
    --state-idle: 199 60% 55%;
    --state-compare: 43 96% 62%;
    --state-swap: 358 75% 59%;
    --state-sorted: 152 60% 50%;
    --state-pivot: 271 76% 68%;
    --state-active-range: 199 89% 64%;
  }
}

@layer base {
  * {
    @apply border-border;
  }

  body {
    @apply bg-background text-foreground;
    background-image:
      linear-gradient(hsl(var(--border) / 0.35) 1px, transparent 1px),
      linear-gradient(90deg, hsl(var(--border) / 0.35) 1px, transparent 1px);
    background-size: 44px 44px;
    background-position: center -1px;
  }

  ::selection {
    background: hsl(var(--accent) / 0.35);
  }

  ::-webkit-scrollbar {
    width: 10px;
    height: 10px;
  }
  ::-webkit-scrollbar-track {
    background: transparent;
  }
  ::-webkit-scrollbar-thumb {
    background: hsl(var(--border));
    border-radius: 999px;
  }
}

@layer utilities {
  .glow-primary {
    box-shadow: 0 0 24px hsl(var(--primary) / 0.35);
  }
  .glow-accent {
    box-shadow: 0 0 24px hsl(var(--accent) / 0.35);
  }
  .text-balance {
    text-wrap: balance;
  }
  .bg-grid-fade {
    -webkit-mask-image: radial-gradient(ellipse at center, black 40%, transparent 85%);
    mask-image: radial-gradient(ellipse at center, black 40%, transparent 85%);
  }
}