/* The shared layer for every page of this site: landing, documentation, design write-up.
 *
 * These three pages had drifted into three designs -- different tokens, three different
 * navigation bars, and a serif body on the write-up against sans everywhere else. Anything a
 * reader carries between pages lives here now and is defined exactly once: the palette, the
 * page chrome, the buttons, the footer. Page-specific styling stays in the page.
 *
 * Load this FIRST, then the page's own <style>, so a page can still specialise. */

/* ---------------------------------------------------- tokens, reset, nav */

:root {
  --bg: #faf9f7;
  --bg-warm: #f4f2ef;
  --bg-card: #ffffff;
  --bg-code: #f4f2ef;
  --bg-highlight: #f4f2ef;

  --text: #1c1a17;
  --text-secondary: #59544c;
  --text-muted: #6e685f;
  --text-faint: #9a938a;

  --accent: #146b52;
  --accent-light: #18805f;
  --accent-glow: rgba(20, 107, 82, 0.10);
  --accent-bg: #e8f2ed;
  --accent-border: #cfe4d9;
  --accent-subtle: #f4f9f6;

  --btn-primary-bg: #146b52;
  --btn-primary-text: #ffffff;

  --border: #e8e4de;
  --border-strong: #d4cec6;

  /* One palette across the whole product, console included: warm neutrals at hue ~35 and a
     single emerald accent. Hue then carries meaning rather than decoration -- emerald for
     healthy, amber for attention, brick for failure, warm graphite for merely in progress. */
  --color-mint: #157a4a;
  --color-mint-bg: #e7f2ea;
  --color-mint-border: #c4e2d1;

  --color-neutral: #6b665d;   /* warm graphite */
  --color-neutral-bg: #f2f0ec;
  --color-neutral-border: #ddd8d0;

  --color-seal: #146b52;
  --color-seal-bg: #e8f2ed;
  --color-seal-border: #cfe4d9;

  --color-red: #9c3428;
  --color-red-bg: #f9eae7;
  --color-red-border: #edcdc7;

  --success: #157a4a;
  --warning: #8a6410;
  --danger: #9c3428;
  --info: #6b665d;

  --radius: 8px;
  --radius-sm: 6px;

  --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, system-ui, sans-serif;
  --font-serif: 'Newsreader', Georgia, 'Times New Roman', serif;
  --font-mono: 'JetBrains Mono', 'SF Mono', 'Fira Code', monospace;

  --nav-height: 60px;
  /* The sticky index column, shared by the documentation page and the walkthrough. */
  --sidebar-width: 270px;
  --bg-sidebar: #f4f2ef;
  --nav-bg: rgba(250, 249, 247, 0.88);
  --content-max-width: 1120px;
}

/* Dark Mode - Obsidian & Crisp White with Subtle Accents */
[data-theme="dark"] {
  --bg: #12110f;
  --bg-warm: #191714;
  --bg-card: #1a1815;
  --bg-code: #191714;
  --bg-highlight: #201d19;

  --text: #f2efe9;
  --text-secondary: #c4bdb2;
  --text-muted: #9a938a;
  --text-faint: #6b665d;

  --accent: #5cbf99;
  --accent-light: #7fd0b1;
  --accent-glow: rgba(92, 191, 153, 0.16);
  --accent-bg: rgba(92, 191, 153, 0.12);
  --accent-border: rgba(92, 191, 153, 0.26);
  --accent-subtle: rgba(92, 191, 153, 0.05);

  --btn-primary-bg: #5cbf99;
  --btn-primary-text: #10241c;

  --border: #2b2721;
  --border-strong: #3d372f;
  --nav-bg: rgba(18, 17, 15, 0.88);
  --bg-sidebar: #191714;

  /* Dark values for the same tokens. */
  --color-mint: #57bd8b;
  --color-mint-bg: rgba(87, 189, 139, 0.14);
  --color-mint-border: rgba(87, 189, 139, 0.28);

  --color-neutral: #9d968c;
  --color-neutral-bg: rgba(157, 150, 140, 0.14);
  --color-neutral-border: rgba(157, 150, 140, 0.28);

  --color-seal: #5cbf99;
  --color-seal-bg: rgba(92, 191, 153, 0.14);
  --color-seal-border: rgba(92, 191, 153, 0.28);

  --color-red: #e08b80;
  --color-red-bg: rgba(224, 139, 128, 0.13);
  --color-red-border: rgba(224, 139, 128, 0.28);

  --success: #57bd8b;
  --warning: #d9a441;
  --danger: #e08b80;
  --info: #9d968c;
}

*,
*::before,
*::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
  -webkit-font-smoothing: antialiased;
}

body {
  font-family: var(--font-sans);
  background: var(--bg);
  color: var(--text);
  line-height: 1.7;
  font-size: 15px;
  transition: background 0.2s ease, color 0.2s ease;
}

/* The site's top bar.
 *
 * Scoped to a direct child of <body> on purpose. As a bare `nav` element selector this also
 * matched the design write-up's page-switcher, which is a <nav> too -- pinning it fixed at the
 * top of the viewport, on top of the real bar, so both were unreadable. Any page-level <nav>
 * nested inside content is left alone. */
body > nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  height: var(--nav-height);
  background: var(--nav-bg);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  border-bottom: 1px solid var(--border);
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 0 clamp(36px, 6vw, 100px);
  transition: background 0.2s ease;
}

[data-theme="dark"] body > nav {
  background: var(--nav-bg);
}

.nav-inner {
  max-width: var(--content-max-width);
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  /* A floor, not a preference. `space-between` distributes whatever is left over, and once the
     brand plus the links exceed the bar there is nothing left over -- so they met with a 2px
     gap and "CUA" ran straight into the first link. A gap cannot be distributed away. */
  gap: 24px;
}

.nav-brand-group {
  display: flex;
  align-items: center;
  gap: 10px;
  text-decoration: none;
  /* Without this the anchor itself resolves to the UA default link blue. The child spans
     happen to cover it today, so it renders correctly and is still wrong -- any text added
     directly to the link would come out blue, in a palette that has no blue in it. */
  color: inherit;
}

.brand-logo-wrap {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 32px;
  height: 32px;
  border-radius: 7px;
  background: var(--bg-highlight);
  border: 1px solid var(--border);
  flex-shrink: 0;
}

.nav-brand-text {
  display: flex;
  align-items: baseline;
  gap: 8px;
}

.nav-brand-title {
  font-weight: 700;
  font-size: 15px;
  color: var(--text);
  letter-spacing: -0.02em;
}

.nav-brand-subtitle {
  color: var(--text-muted);
  font-weight: 400;
  font-size: 13px;
}

.nav-right {
  display: flex;
  /* The text links carry most of this; the GitHub button gets a wider gap of its own below so
     the group of links reads as one set and the button as a separate control. */
  gap: 26px;
  align-items: center;
}

.nav-right .nav-github-btn {
  margin-left: 6px;
}

.nav-link {
  font-size: 13px;
  color: var(--text-secondary);
  text-decoration: none;
  font-weight: 500;
  transition: color 0.15s;
}

.nav-link:hover {
  color: var(--text);
}

/* Marks the page you are on. Only the documentation page defined this, so "you are here" was a
   documentation-only idea; now every page can say it the same way. Underlined in the accent
   rather than in text colour, so the current page reads as selected and not merely bold. */
.nav-link.active {
  color: var(--text);
  font-weight: 600;
  border-bottom: 2px solid var(--accent);
  padding-bottom: 2px;
}

/* GitHub Button in Nav */
.nav-github-btn {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  border: 1px solid var(--border-strong);
  padding: 5px 12px;
  border-radius: 6px;
  font-size: 12px;
  font-weight: 600;
  color: var(--text);
  background: var(--bg-card);
  text-decoration: none;
  transition: all 0.15s;
}

.nav-github-btn:hover {
  border-color: var(--border-strong);
  color: var(--text);
  background: var(--bg-highlight);
}

.nav-github-btn svg {
  flex-shrink: 0;
}

.theme-toggle {
  background: transparent;
  border: 1px solid var(--border);
  border-radius: 6px;
  width: 34px;
  height: 34px;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  color: var(--text-secondary);
  transition: all 0.15s;
}

.theme-toggle:hover {
  color: var(--text);
  border-color: var(--border-strong);
  background: var(--bg-highlight);
}

/* MAIN CONTAINER - Generous horizontal padding from left and right */
.container,
.page-container {
  max-width: var(--content-max-width);
  margin: 0 auto;
  padding: 0 clamp(32px, 6vw, 100px);
}

/* ------------------------------------------------------------------ buttons */

.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 10px 20px;
  border-radius: 6px;
  font-size: 13px;
  font-weight: 600;
  text-decoration: none;
  transition: all 0.15s;
}

.btn-primary {
  background: var(--btn-primary-bg);
  color: var(--btn-primary-text);
  border: 1px solid var(--btn-primary-bg);
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
}

.btn-primary:hover {
  background: var(--accent-light);
  border-color: var(--accent-light);
  transform: translateY(-1px);
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
}

[data-theme="dark"] .btn-primary:hover {
  /* Was a literal zinc, left over from the monochrome palette -- the one place a hover
     stepped outside the token set and landed on a different hue than the button itself. */
  background: var(--accent-light);
  border-color: var(--accent-light);
}

.btn-github {
  border: 1px solid var(--border-strong);
  color: var(--text);
  background: var(--bg-card);
}

.btn-github:hover {
  border-color: var(--border-strong);
  color: var(--text);
  background: var(--bg-highlight);
  transform: translateY(-1px);
}

.btn-secondary {
  border: 1px solid var(--border);
  color: var(--text-secondary);
  background: transparent;
}

.btn-secondary:hover {
  background: var(--bg-warm);
  color: var(--text);
  border-color: var(--border-strong);
}


/* ------------------------------------------------------- section headings */

.section-title {
  font-family: var(--font-serif);
  font-size: 30px;
  font-weight: 600;
  margin-bottom: 8px;
  letter-spacing: -0.02em;
  text-align: left;
}

.section-subtitle {
  font-size: 14px;
  color: var(--text-muted);
  margin-bottom: 36px;
  max-width: 740px;
  text-align: left;
}


/* ------------------------------------------------------------------- footer */

footer {
  border-top: 1px solid var(--border);
  padding: 36px clamp(40px, 7vw, 110px);
  display: flex;
  justify-content: center;
  align-items: center;
  font-size: 13px;
  color: var(--text-muted);
}

.footer-inner {
  max-width: var(--content-max-width);
  width: 100%;
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 16px;
}

.footer-left {
  display: flex;
  align-items: center;
  gap: 8px;
}

footer a {
  color: var(--text-secondary);
  text-decoration: none;
  transition: color 0.15s;
  font-weight: 500;
}

footer a:hover {
  color: var(--text);
}

/* RESPONSIVE */


/* ------------------------------------------------------- the bar at narrow widths
 *
 * Four text links and a button do not fit beside the brand much below a laptop, and the bar has
 * no room to wrap: it is a fixed height. So give ground in the order the content can least
 * afford to lose it -- first the gaps, then the brand's second line, then the button's label,
 * which is the one element that still reads perfectly as an icon alone. */

@media (max-width: 900px) {
  .nav-right {
    gap: 16px;
  }

  .nav-right .nav-github-btn {
    margin-left: 2px;
  }
}

@media (max-width: 720px) {
  .nav-brand-subtitle {
    display: none;
  }

  .nav-right {
    gap: 13px;
  }
}

@media (max-width: 560px) {
  /* Icon only. The mark is recognisable and the link's aria-label still says where it goes. */
  .nav-github-btn span {
    display: none;
  }

  .nav-github-btn {
    padding: 6px 8px;
  }
}