/* ==========================================================================
   tokens.css — the single source of truth for every design value.
   --------------------------------------------------------------------------
   RULE: No other stylesheet may contain a raw design value (color, size,
   spacing, radius, shadow, duration, font). Everything is declared here once
   and consumed with var(). If a value is needed that does not exist yet,
   add a token here first.

   Layers:
     1. Primitives  — raw palette and scales. Never used directly in styles.css.
     2. Semantic    — meaning-based aliases. These are what styles.css uses.
     3. Theme       — semantic tokens redefined for dark mode.

   Breakpoints (documented here for reference; media queries cannot read
   custom properties, so these literals are repeated in styles.css):
     --bp-sm: 480px | --bp-md: 720px | --bp-lg: 960px | --bp-xl: 1180px
   ========================================================================== */

:root {
  /* ======================================================================
     1. PRIMITIVES
     ====================================================================== */

  /* --- Neutral ramp ---------------------------------------------------- */
  --palette-neutral-0: #ffffff;
  --palette-neutral-25: #fbfcfd;
  --palette-neutral-50: #f6f8fa;
  --palette-neutral-100: #eceff3;
  --palette-neutral-200: #dde2e9;
  --palette-neutral-300: #c3cad4;
  --palette-neutral-400: #98a2b0;
  --palette-neutral-500: #6e7889;
  --palette-neutral-600: #515b6b;
  --palette-neutral-700: #3a434f;
  --palette-neutral-800: #252c36;
  --palette-neutral-900: #171d25;
  --palette-neutral-950: #0e1319;
  --palette-neutral-1000: #080b0f;

  /* --- Accent ramp (indigo) -------------------------------------------- */
  --palette-accent-50: #eef1ff;
  --palette-accent-100: #dfe4ff;
  --palette-accent-200: #c3ccff;
  --palette-accent-300: #9ea9fc;
  --palette-accent-400: #7d86f7;
  --palette-accent-500: #5b61ea;
  --palette-accent-600: #4a49d4;
  --palette-accent-700: #3c3aad;
  --palette-accent-800: #2f2f84;
  --palette-accent-900: #232464;

  /* --- Signal ramps ----------------------------------------------------- */
  --palette-danger-100: #ffe3e0;
  --palette-danger-300: #ff9e95;
  --palette-danger-500: #e5484d;
  --palette-danger-700: #a32b30;

  --palette-warning-100: #fff2d6;
  --palette-warning-300: #ffce6b;
  --palette-warning-500: #d98b0b;
  --palette-warning-700: #96600a;

  --palette-success-100: #dcf7e6;
  --palette-success-300: #82dfa6;
  --palette-success-500: #2f9e5f;
  --palette-success-700: #1f6b41;

  /* --- Transparencies --------------------------------------------------- */
  --palette-alpha-light-08: rgba(255, 255, 255, 0.08);
  --palette-alpha-light-12: rgba(255, 255, 255, 0.12);
  --palette-alpha-light-70: rgba(255, 255, 255, 0.7);
  --palette-alpha-light-85: rgba(255, 255, 255, 0.85);
  --palette-alpha-dark-04: rgba(13, 18, 24, 0.04);
  --palette-alpha-dark-08: rgba(13, 18, 24, 0.08);
  --palette-alpha-dark-14: rgba(13, 18, 24, 0.14);
  --palette-alpha-dark-70: rgba(13, 18, 24, 0.7);
  --palette-alpha-dark-85: rgba(13, 18, 24, 0.85);
  --palette-alpha-accent-10: rgba(91, 97, 234, 0.1);
  --palette-alpha-accent-18: rgba(91, 97, 234, 0.18);
  --palette-alpha-accent-30: rgba(91, 97, 234, 0.3);
  --palette-alpha-none: rgba(0, 0, 0, 0);

  /* --- Typography ------------------------------------------------------- */
  --font-family-sans: "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI",
    Roboto, "Helvetica Neue", Arial, sans-serif;
  --font-family-mono: "JetBrains Mono", "SFMono-Regular", ui-monospace,
    "Cascadia Mono", Menlo, Consolas, "Liberation Mono", monospace;

  --font-size-2xs: 0.6875rem;
  --font-size-xs: 0.75rem;
  --font-size-sm: 0.875rem;
  --font-size-md: 1rem;
  --font-size-lg: 1.125rem;
  --font-size-xl: 1.25rem;
  --font-size-2xl: 1.5rem;
  --font-size-3xl: 1.875rem;
  --font-size-4xl: 2.25rem;
  --font-size-5xl: 3rem;
  --font-size-6xl: 3.75rem;

  --font-size-hero: clamp(2.25rem, 1.35rem + 3.6vw, 4rem);
  --font-size-section-title: clamp(1.75rem, 1.25rem + 2vw, 2.75rem);

  --font-weight-regular: 400;
  --font-weight-medium: 500;
  --font-weight-semibold: 600;
  --font-weight-bold: 700;

  --line-height-none: 1;
  --line-height-tight: 1.15;
  --line-height-snug: 1.3;
  --line-height-normal: 1.5;
  --line-height-relaxed: 1.65;

  --letter-spacing-tighter: -0.03em;
  --letter-spacing-tight: -0.015em;
  --letter-spacing-normal: 0em;
  --letter-spacing-wide: 0.02em;
  --letter-spacing-widest: 0.1em;

  /* --- Spacing scale ---------------------------------------------------- */
  --space-0: 0rem;
  --space-1: 0.25rem;
  --space-2: 0.5rem;
  --space-3: 0.75rem;
  --space-4: 1rem;
  --space-5: 1.25rem;
  --space-6: 1.5rem;
  --space-7: 1.75rem;
  --space-8: 2rem;
  --space-10: 2.5rem;
  --space-12: 3rem;
  --space-14: 3.5rem;
  --space-16: 4rem;
  --space-20: 5rem;
  --space-24: 6rem;
  --space-32: 8rem;

  /* --- Radii ------------------------------------------------------------ */
  --radius-xs: 0.1875rem;
  --radius-sm: 0.3125rem;
  --radius-md: 0.5rem;
  --radius-lg: 0.75rem;
  --radius-xl: 1rem;
  --radius-2xl: 1.5rem;
  --radius-pill: 62.4375rem;

  /* --- Borders ---------------------------------------------------------- */
  --border-width-none: 0;
  --border-width-thin: 1px;
  --border-width-thick: 2px;
  --border-width-accent: 3px;

  /* --- Elevation -------------------------------------------------------- */
  --shadow-none: none;
  --shadow-xs: 0 1px 2px var(--palette-alpha-dark-04);
  --shadow-sm: 0 1px 3px var(--palette-alpha-dark-08),
    0 1px 2px var(--palette-alpha-dark-04);
  --shadow-md: 0 4px 12px var(--palette-alpha-dark-08),
    0 2px 4px var(--palette-alpha-dark-04);
  --shadow-lg: 0 14px 34px var(--palette-alpha-dark-14),
    0 4px 10px var(--palette-alpha-dark-08);
  --shadow-accent: 0 8px 24px var(--palette-alpha-accent-30);

  /* --- Motion ----------------------------------------------------------- */
  --duration-instant: 90ms;
  --duration-fast: 150ms;
  --duration-base: 220ms;
  --duration-slow: 360ms;
  --easing-standard: cubic-bezier(0.2, 0, 0.2, 1);
  --easing-out: cubic-bezier(0.16, 1, 0.3, 1);
  --transition-colors: color var(--duration-fast) var(--easing-standard),
    background-color var(--duration-fast) var(--easing-standard),
    border-color var(--duration-fast) var(--easing-standard);
  --transition-transform: transform var(--duration-base) var(--easing-out);
  --transition-shadow: box-shadow var(--duration-base) var(--easing-out);

  /* --- Layout ----------------------------------------------------------- */
  --layout-max-width: 71rem;
  --layout-prose-width: 46rem;
  --layout-gutter: var(--space-6);
  --layout-gutter-lg: var(--space-8);
  --layout-header-height: 4.25rem;
  --section-space-block: clamp(4rem, 2.5rem + 6vw, 7.5rem);
  --grid-gap: var(--space-6);
  --grid-gap-lg: var(--space-8);

  /* --- Stacking --------------------------------------------------------- */
  --z-base: 0;
  --z-raised: 10;
  --z-sticky: 100;

  /* --- Sizing ----------------------------------------------------------- */
  --size-icon-sm: 1rem;
  --size-icon-md: 1.25rem;
  --size-icon-lg: 1.5rem;
  --size-badge-dot: 0.4375rem;
  --size-step-marker: 2.5rem;
  --size-rule-thin: 1px;
  --size-focus-ring: 3px;
  --size-focus-offset: 2px;

  /* ======================================================================
     2. SEMANTIC TOKENS — light theme (default)
     ====================================================================== */

  /* Surfaces */
  --color-bg: var(--palette-neutral-0);
  --color-bg-subtle: var(--palette-neutral-50);
  --color-surface: var(--palette-neutral-0);
  --color-surface-subtle: var(--palette-neutral-50);
  --color-surface-raised: var(--palette-neutral-0);
  --color-surface-overlay: var(--palette-alpha-light-85);
  --color-surface-code: var(--palette-neutral-950);

  /* Text */
  --color-text: var(--palette-neutral-900);
  --color-text-muted: var(--palette-neutral-600);
  --color-text-subtle: var(--palette-neutral-500);
  --color-text-accent: var(--palette-accent-600);
  --color-text-on-accent: var(--palette-neutral-0);
  --color-text-code: var(--palette-neutral-100);

  /* Lines */
  --color-border: var(--palette-neutral-200);
  --color-border-strong: var(--palette-neutral-300);
  --color-border-subtle: var(--palette-neutral-100);
  --color-border-accent: var(--palette-accent-500);

  /* Contrast panel — the dark feature bands (insight, security).
     These stay dark in BOTH themes. They are deliberately NOT "inverse"
     tokens: flipping them in dark mode would put dark text on dark cards. */
  --color-panel-bg: var(--palette-neutral-950);
  --color-panel-surface: var(--palette-neutral-900);
  --color-panel-border: var(--palette-alpha-light-12);
  --color-panel-text: var(--palette-neutral-0);
  --color-panel-text-muted: var(--palette-neutral-300);
  --color-panel-eyebrow: var(--palette-accent-300);

  /* Accent */
  --color-accent: var(--palette-accent-600);
  --color-accent-hover: var(--palette-accent-700);
  --color-accent-active: var(--palette-accent-800);
  --color-accent-soft: var(--palette-accent-50);
  --color-accent-soft-border: var(--palette-accent-200);

  /* Signals */
  --color-danger: var(--palette-danger-500);
  --color-danger-soft: var(--palette-danger-100);
  --color-warning: var(--palette-warning-500);
  --color-warning-soft: var(--palette-warning-100);
  --color-success: var(--palette-success-500);
  --color-success-soft: var(--palette-success-100);

  /* Focus */
  --color-focus-ring: var(--palette-accent-500);

  /* Component-level */
  --color-header-bg: var(--palette-alpha-light-85);
  --color-card-bg: var(--color-surface);
  --color-card-border: var(--color-border);
  --color-card-shadow: var(--shadow-sm);
  --color-card-shadow-hover: var(--shadow-lg);
}

/* ==========================================================================
   3. THEME — dark mode. Only semantic tokens are reassigned.
   ========================================================================== */

@media (prefers-color-scheme: dark) {
  :root {
    /* Surfaces */
    --color-bg: var(--palette-neutral-1000);
    --color-bg-subtle: var(--palette-neutral-950);
    --color-surface: var(--palette-neutral-950);
    --color-surface-subtle: var(--palette-neutral-900);
    --color-surface-raised: var(--palette-neutral-900);
    --color-surface-overlay: var(--palette-alpha-dark-85);
    --color-surface-code: var(--palette-neutral-950);

    /* Text */
    --color-text: var(--palette-neutral-50);
    --color-text-muted: var(--palette-neutral-400);
    --color-text-subtle: var(--palette-neutral-500);
    --color-text-accent: var(--palette-accent-300);
    --color-text-on-accent: var(--palette-neutral-0);
    --color-text-code: var(--palette-neutral-100);

    /* Lines */
    --color-border: var(--palette-neutral-800);
    --color-border-strong: var(--palette-neutral-700);
    --color-border-subtle: var(--palette-neutral-900);
    --color-border-accent: var(--palette-accent-400);

    /* Contrast panel — stays dark, but lifted off the darker page
       background so the band still reads as a distinct section. */
    --color-panel-bg: var(--palette-neutral-950);
    --color-panel-surface: var(--palette-neutral-800);
    --color-panel-border: var(--palette-alpha-light-08);
    --color-panel-text: var(--palette-neutral-50);
    --color-panel-text-muted: var(--palette-neutral-400);
    --color-panel-eyebrow: var(--palette-accent-300);

    /* Accent */
    --color-accent: var(--palette-accent-500);
    --color-accent-hover: var(--palette-accent-400);
    --color-accent-active: var(--palette-accent-300);
    --color-accent-soft: var(--palette-alpha-accent-18);
    --color-accent-soft-border: var(--palette-alpha-accent-30);

    /* Signals */
    --color-danger: var(--palette-danger-300);
    --color-danger-soft: var(--palette-alpha-dark-14);
    --color-warning: var(--palette-warning-300);
    --color-warning-soft: var(--palette-alpha-dark-14);
    --color-success: var(--palette-success-300);
    --color-success-soft: var(--palette-alpha-dark-14);

    /* Focus */
    --color-focus-ring: var(--palette-accent-300);

    /* Elevation reads differently on dark surfaces */
    --shadow-sm: 0 1px 3px var(--palette-alpha-dark-70);
    --shadow-md: 0 6px 16px var(--palette-alpha-dark-70);
    --shadow-lg: 0 18px 40px var(--palette-alpha-dark-85);

    /* Component-level */
    --color-header-bg: var(--palette-alpha-dark-85);
  }
}