/* brand.css : design tokens, font faces and the dark-scheme remap. Nothing else.

   FILE ORDER IS A CONTRACT (the kit's tools read this file):
     1. @font-face        2. :root tokens        3. the dark remap, LAST.
   Why last: a rule in this file that follows the dark block would silently win over it (lesson CS-01).
   Dark mode is ONE remap of ROLE tokens under prefers-color-scheme: no toggle, no stored preference.
   site.css is written against these tokens only: no hex value appears outside this file.

   LAYERS: --rh-* the brand palette (raw, never words); --d-* DERIVED, off-palette, each with its ratio;
   roles (--ground, --text ...) remapped by the dark block; --inv-* an ALWAYS-DARK ground, both schemes.

   GREEN LEADS and WORDS ON COLOUR: DESIGN.md sec. 3 (S31: this header's two paragraphs on them moved to
   _unsorted/s31-state/comments-moved-S31.txt). */

/* 1. */
@font-face {
  font-family: "Poppins";
  font-style: normal;
  font-weight: 400;
  font-display: swap;
  src: url("../fonts/poppins-400.woff2") format("woff2");
  unicode-range: U+0000-00FF, U+0131, U+0152-0153, U+02BB-02BC, U+02C6, U+02DA, U+02DC, U+0304, U+0308, U+0329, U+2000-206F, U+20AC, U+2122, U+2191, U+2193, U+2212, U+2215, U+FEFF, U+FFFD;
}
@font-face {
  font-family: "Poppins";
  font-style: normal;
  font-weight: 500;
  font-display: swap;
  src: url("../fonts/poppins-500.woff2") format("woff2");
  unicode-range: U+0000-00FF, U+0131, U+0152-0153, U+02BB-02BC, U+02C6, U+02DA, U+02DC, U+0304, U+0308, U+0329, U+2000-206F, U+20AC, U+2122, U+2191, U+2193, U+2212, U+2215, U+FEFF, U+FFFD;
}
@font-face {
  font-family: "Poppins";
  font-style: normal;
  font-weight: 600;
  font-display: swap;
  src: url("../fonts/poppins-600.woff2") format("woff2");
  unicode-range: U+0000-00FF, U+0131, U+0152-0153, U+02BB-02BC, U+02C6, U+02DA, U+02DC, U+0304, U+0308, U+0329, U+2000-206F, U+20AC, U+2122, U+2191, U+2193, U+2212, U+2215, U+FEFF, U+FFFD;
}
@font-face {
  font-family: "Poppins";
  font-style: normal;
  font-weight: 700;
  font-display: swap;
  src: url("../fonts/poppins-700.woff2") format("woff2");
  unicode-range: U+0000-00FF, U+0131, U+0152-0153, U+02BB-02BC, U+02C6, U+02DA, U+02DC, U+0304, U+0308, U+0329, U+2000-206F, U+20AC, U+2122, U+2191, U+2193, U+2212, U+2215, U+FEFF, U+FFFD;
}

/* 2. */
:root {
  /* Declares both schemes so form controls, [...] */
  color-scheme: light dark;

  /* Brand palette (raw). [...] */
  --rh-mint: #47D69E;
  --rh-pine: #163E35;
  --rh-ink: #0A1412;
  /* The July 2024 book's nine: [...] */
  --rh-forest: #0A3E3B;
  --rh-green: #00CA74;
  --rh-lime: #B9FF84;
  --rh-indigo: #242466;
  --rh-blue: #434CEA;
  --rh-sky: #7DDBFF;
  --rh-vermilion: #FC4219;
  --rh-orange: #FF6A00;
  --rh-amber: #FF9D1A;
  --rh-night: #070824;
  --rh-white: #FFFFFF;
  --rh-black: #000000;

  /* Derived (OFF-PALETTE, flagged). */
  --d-mint-wash: #EDFBF5;
  --d-mint-tint: #A3EACE;
  --d-mint-text: #0F6E4E;
  --d-green-grey: #4F615B;
  --d-line: #CDE6DC;
  --d-error: #BA3112;
  --d-sky-wash: #E7F9FF;
  --d-amber-wash: #FFF0DD;
  --d-red-wash: #FED9D1;
  --d-ink-raised: #0E1B17;
  --d-ink-tint: #0F231D;
  --d-ink-pale: #B4C6BF;
  --d-ink-border: #7E968E;
  --d-ink-line: #24443B;
  --d-pine-pale: #C3D9D1;
  --d-pine-border: #8DB5A7;
  --d-pine-line: #2E5A4F;
  --d-pine-raised: #1E4B40;
  --d-print-grey: #444444;
  /* Home's transition (D2): [...] */
  --d-tr-blue: #D8F4FF;
  --d-tr-mid: #D0F4F1;
  --d-tr-green: #C8F3E2;
  --d-tr-blue-dark: #141A34;
  --d-tr-mid-dark: #12222C;
  --d-tr-green-dark: #102924;

  /* Roles, light scheme. */
  --ground: var(--rh-white);
  --surface: var(--rh-white);
  --tint: var(--d-mint-wash);
  --text: var(--rh-ink);
  --muted: var(--d-green-grey);
  --heading: var(--rh-pine);
  --link: var(--d-mint-text);
  --link-hover: var(--rh-pine);
  --accent: var(--rh-pine);
  --accent-hover: var(--rh-ink);
  --on-accent: var(--rh-white);
  --focus: var(--rh-ink);
  --focus-halo: var(--rh-white);
  --ui-border: var(--d-green-grey);
  --line: var(--d-line);
  --success: var(--rh-pine);
  --error: var(--d-error);
  --footer-bg: var(--rh-pine);
  --tr-from: var(--d-tr-blue);
  --tr-mid: var(--d-tr-mid);
  --tr-to: var(--d-tr-green);

  /* The logo (D3): [...] */
  --logo-mark: var(--rh-mint);
  --on-bright: var(--rh-ink);

  /* Notice (callout) roles: [...] */
  --notice-info-bg: var(--d-sky-wash);     --notice-info-bar: var(--rh-blue);       --notice-info-ink: var(--rh-indigo);
  --notice-warning-bg: var(--d-amber-wash);--notice-warning-bar: var(--rh-amber);   --notice-warning-ink: var(--rh-ink);
  --notice-error-bg: var(--d-red-wash);    --notice-error-bar: var(--rh-vermilion); --notice-error-ink: var(--d-error);
  --notice-success-bg: var(--d-mint-wash); --notice-success-bar: var(--rh-mint);    --notice-success-ink: var(--rh-pine);

  /* Always-dark ground (.band--dark, [...] */
  --inv-bg: var(--rh-pine);
  --inv-surface: var(--d-pine-raised);
  --inv-text: var(--rh-white);
  --inv-muted: var(--d-pine-pale);
  --inv-link: var(--rh-mint);
  --inv-link-hover: var(--d-mint-tint);
  --inv-accent: var(--rh-mint);
  --inv-accent-hover: var(--d-mint-tint);
  --inv-on-accent: var(--rh-ink);
  --inv-focus: var(--rh-white);
  --inv-halo: var(--rh-ink);
  --inv-border: var(--d-pine-border);
  --inv-line: var(--d-pine-line);

  /* Decoration (shapes only, [...] */
  --deco-mark-a: var(--rh-pine); --deco-mark-b: var(--rh-mint);
  --deco-hero-ground: var(--d-mint-tint); --deco-hero-ink: var(--rh-pine);

  /* Type. Poppins first; [...] */
  --font-body: "Poppins", system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  --fs-sm: 0.875rem;
  --fs-body: 1.0625rem;
  --fs-lead: clamp(1.1875rem, 1.1rem + 0.45vw, 1.375rem);
  --fs-h4: 1.1875rem;
  --fs-h3: clamp(1.25rem, 1.15rem + 0.5vw, 1.5rem);
  --fs-h2: clamp(1.625rem, 1.35rem + 1.3vw, 2.375rem);
  --fs-h1: clamp(2rem, 1.5rem + 2.4vw, 3.25rem);
  --fs-display: clamp(2.25rem, 1.55rem + 3.4vw, 4rem);
  --fs-stat: clamp(2.75rem, 2.1rem + 3vw, 4.25rem);
  --lh-body: 1.5;
  --lh-snug: 1.3;
  --lh-tight: 1.15;

  /* Spacing (rem, so it follows the reader's text size). */
  --sp-1: 0.25rem;
  --sp-2: 0.5rem;
  --sp-3: 0.75rem;
  --sp-4: 1rem;
  --sp-5: 1.5rem;
  --sp-6: 2rem;
  --sp-7: 3rem;
  --sp-8: 4rem;
  --sp-9: 6rem;
  --band-pad: clamp(3rem, 2rem + 4vw, 5.5rem);

  /* Layout. --header-h is the rendered height of the header bar: [...] */
  --container: 72rem;
  --container-narrow: 46rem;
  --measure: 62ch;
  --gutter: clamp(1rem, 0.5rem + 2.2vw, 2rem);
  --header-h: 3.75rem;
  --target: 2.75rem;

  --radius-sm: 0.25rem;
  --radius: 0.5rem;
  --radius-lg: 1rem;

  /* Focus ring geometry: [...] */
  --ring-w: 3px;
  --ring-gap: 2px;

  /* Motion (used only inside prefers-reduced-motion: [...] */
  --dur-fast: 120ms;
  --dur: 200ms;
  --dur-slow: 700ms;
  --ease: cubic-bezier(0.2, 0.6, 0.2, 1);

  --z-header: 100;
  --z-skip: 200;
}

/* Header height steps up with the desktop layout (the menu button collapses below 60rem). [...] */
@media (min-width: 60rem) {
  :root { --header-h: 4.5rem; }
}

/* 3. */
@media (prefers-color-scheme: dark) {
  :root {
    --ground: var(--rh-ink);
    --surface: var(--d-ink-raised);
    --tint: var(--d-ink-tint);
    --text: var(--rh-white);
    --muted: var(--d-ink-pale);
    --heading: var(--rh-white);
    --link: var(--rh-mint);
    --link-hover: var(--d-mint-tint);
    --accent: var(--rh-mint);
    --accent-hover: var(--d-mint-tint);
    --on-accent: var(--rh-ink);
    --focus: var(--rh-white);
    --focus-halo: var(--rh-ink);
    --ui-border: var(--d-ink-border);
    --line: var(--d-ink-line);
    --success: var(--rh-mint);
    --error: var(--rh-vermilion);
    --tr-from: var(--d-tr-blue-dark);
    --tr-mid: var(--d-tr-mid-dark);
    --tr-to: var(--d-tr-green-dark);

    --deco-mark-a: var(--rh-mint); --deco-mark-b: var(--d-mint-tint);
    --deco-hero-ground: var(--rh-pine); --deco-hero-ink: var(--rh-mint);

    --notice-info-bg: var(--d-ink-raised);    --notice-info-bar: var(--rh-sky);      --notice-info-ink: var(--rh-sky);
    --notice-warning-bg: var(--d-ink-raised); --notice-warning-bar: var(--rh-amber); --notice-warning-ink: var(--rh-amber);
    --notice-error-bg: var(--d-ink-raised);   --notice-error-bar: var(--rh-vermilion); --notice-error-ink: var(--rh-vermilion);
    --notice-success-bg: var(--d-ink-raised); --notice-success-bar: var(--rh-mint);  --notice-success-ink: var(--rh-mint);
  }
}