/* C++ Alliance Insights homepage.
   Tokens come first and are defined once. The dark set is repeated for the two
   ways it can apply: the OS setting (unless the visitor chose light) and an
   explicit choice. The page sends a Content-Security-Policy that forbids inline
   styles, so nothing here may rely on a style attribute. */

:root {
  --font-sans: "IBM Plex Sans", system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  --font-mono: "IBM Plex Mono", ui-monospace, SFMono-Regular, Menlo, Consolas, "Liberation Mono", monospace;
  --gutter: clamp(16px, 5vw, 48px);
  --radius: 8px;
  --max-width: 1120px;

  color-scheme: light;
  --bg: #f6f8fa;
  --card: #ffffff;
  --card-grad: linear-gradient(180deg, #ffffff 0%, #fafbfc 100%);
  --ink: #1c2128;
  --ink-muted: #57606a;
  --line: #d0d7de;
  --link: #0950a1;
  --accent: #a91c21;
  --focus: #0950a1;
  --gold: #d4af37;
  --gold-deep: #8b6a2a;
  --chip-bg: #eaeef2;
  --chip-ink: #24292f;
  --shadow: 0 1px 2px rgba(27, 31, 36, 0.06), 0 4px 12px rgba(27, 31, 36, 0.06);
  --shadow-hover: 0 2px 4px rgba(27, 31, 36, 0.08), 0 8px 24px rgba(27, 31, 36, 0.1);

  /* Navy parts keep the same colors in both themes. */
  --banner-grad: linear-gradient(90deg, #081830 0%, #12263f 20%, #11253e 72%, #132842 90%, #081830 100%);
  --banner-ink: #ffffff;
  --banner-muted: #c7cede;
  --band-bg: #0e1b2f;
  --band-ink: #e6e9ee;
  --band-muted: #c7cede;
  --band-link: #80b8ff;
  --footer-bg: #081830;
  --footer-ink: #c7cede;
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    color-scheme: dark;
    --bg: #171d26;
    --card: #0f1419;
    --card-grad: linear-gradient(180deg, #0f1419 0%, #131922 100%);
    --ink: #e6e9ee;
    --ink-muted: #a9b2bf;
    --line: #2b333f;
    --link: #80b8ff;
    --accent: #ff7a70;
    --focus: #d4af37;
    --chip-bg: #1e2530;
    --chip-ink: #c7cede;
    --shadow: 0 1px 3px rgba(0, 0, 0, 0.3);
    --shadow-hover: 0 4px 16px rgba(0, 0, 0, 0.4);
  }
}

:root[data-theme="dark"] {
  color-scheme: dark;
  --bg: #171d26;
  --card: #0f1419;
  --card-grad: linear-gradient(180deg, #0f1419 0%, #131922 100%);
  --ink: #e6e9ee;
  --ink-muted: #a9b2bf;
  --line: #2b333f;
  --link: #80b8ff;
  --accent: #ff7a70;
  --focus: #d4af37;
  --chip-bg: #1e2530;
  --chip-ink: #c7cede;
  --shadow: 0 1px 3px rgba(0, 0, 0, 0.3);
  --shadow-hover: 0 4px 16px rgba(0, 0, 0, 0.4);
}

/* Base */

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

[hidden] { display: none !important; }

html {
  -webkit-text-size-adjust: 100%;
  text-size-adjust: 100%;
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: var(--font-sans);
  font-size: 1rem;
  line-height: 1.5;
  -webkit-font-smoothing: antialiased;
}

img { display: block; max-width: 100%; height: auto; }

a {
  color: var(--link);
  text-underline-offset: 0.18em;
}
a:hover { text-decoration-thickness: 2px; }

:focus-visible {
  outline: 3px solid var(--focus);
  outline-offset: 2px;
}

.skip-link {
  position: absolute;
  left: var(--gutter);
  top: 8px;
  z-index: 10;
  padding: 10px 16px;
  background: var(--card);
  color: var(--link);
  border: 2px solid var(--focus);
  border-radius: var(--radius);
  font-weight: 600;
  transform: translateY(-200%);
}
.skip-link:focus { transform: none; }

main:focus { outline: none; }

.wrap {
  max-width: var(--max-width);
  margin: 0 auto;
  padding-inline: var(--gutter);
}

/* Masthead */

.masthead {
  background: var(--banner-grad);
  color: var(--banner-ink);
  border-bottom: 3px solid var(--gold-deep);
}

.masthead-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 24px var(--gutter);
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 16px 20px;
}

.masthead :focus-visible,
.support :focus-visible,
.footer :focus-visible { outline-color: var(--gold); }

.brand {
  flex: none;
  border-radius: var(--radius);
}
.brand-logo { width: 61px; height: 56px; }

.brand-text { flex: 1 1 16rem; min-width: 0; }

.brand-title {
  margin: 0;
  font-size: clamp(1.375rem, 1.1rem + 1.2vw, 1.875rem);
  line-height: 1.2;
  font-weight: 700;
  letter-spacing: -0.01em;
}

.brand-sub {
  margin: 4px 0 0;
  color: var(--banner-muted);
}

.theme-toggle {
  display: none;
  align-items: center;
  gap: 8px;
  min-height: 44px;
  padding: 0 16px;
  border: 1px solid rgba(255, 255, 255, 0.28);
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.08);
  color: var(--banner-ink);
  font: inherit;
  font-size: 0.9375rem;
  font-weight: 500;
  cursor: pointer;
}
.js .theme-toggle { display: inline-flex; }
.theme-toggle:hover {
  background: rgba(255, 255, 255, 0.16);
  border-color: rgba(255, 255, 255, 0.5);
}
.theme-toggle svg {
  width: 16px;
  height: 16px;
  fill: none;
  stroke: currentColor;
  stroke-width: 1.5;
  stroke-linecap: round;
  stroke-linejoin: round;
}

/* Intro and project cards */

.intro { padding-block: 40px 8px; }

.lead {
  margin: 0;
  max-width: 68ch;
  font-size: 1.125rem;
}

.projects { padding-block: 32px 56px; }

.section-label {
  margin: 0 0 16px;
  color: var(--ink-muted);
  font-size: 0.8125rem;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.cards {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 24px;
  grid-template-columns: repeat(auto-fit, minmax(min(100%, 22rem), 1fr));
}

.card {
  position: relative;
  display: flex;
  flex-direction: column;
  padding: 24px;
  background: var(--card-grad);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  transition: border-color 0.15s ease, box-shadow 0.15s ease;
}
.card:hover {
  border-color: var(--gold-deep);
  box-shadow: var(--shadow-hover);
}

.card-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  margin-bottom: 16px;
}

.card-icon {
  display: grid;
  place-items: center;
  width: 44px;
  height: 44px;
  border-radius: var(--radius);
  background: var(--chip-bg);
  color: var(--accent);
}
.card-icon svg {
  width: 24px;
  height: 24px;
  fill: none;
  stroke: currentColor;
  stroke-width: 1.75;
  stroke-linecap: round;
  stroke-linejoin: round;
}

.path-chip {
  padding: 2px 10px;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: var(--chip-bg);
  color: var(--chip-ink);
  font-family: var(--font-mono);
  font-size: 0.8125rem;
}

.card-title {
  margin: 0 0 8px;
  font-size: 1.25rem;
  line-height: 1.3;
  font-weight: 600;
}

/* The title link covers the whole card, so the card is one big target. */
.card-link {
  color: var(--ink);
  text-decoration: none;
}
.card-link::after {
  content: "";
  position: absolute;
  inset: 0;
  border-radius: var(--radius);
}
.card:hover .card-link {
  text-decoration: underline;
  text-decoration-thickness: 2px;
  text-underline-offset: 0.18em;
}
.card-link:focus-visible { outline: none; }
.card-link:focus-visible::after {
  outline: 3px solid var(--focus);
  outline-offset: 2px;
}

.card-text {
  margin: 0 0 16px;
  color: var(--ink-muted);
}

.card-links {
  list-style: none;
  margin: 0 0 12px;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 0 20px;
}
.card-links a {
  position: relative;
  z-index: 1;
  display: inline-flex;
  align-items: center;
  min-height: 44px;
}

.card-cta {
  margin-top: auto;
  color: var(--link);
  font-weight: 600;
}

/* Support band */

.support {
  background: var(--band-bg);
  color: var(--band-ink);
}

.support-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 40px var(--gutter);
  display: grid;
  grid-template-columns: auto 1fr;
  align-items: center;
  gap: 24px 40px;
}
.support-logo { width: 87px; height: 80px; }

.support h2 {
  margin: 0 0 8px;
  font-size: 1.375rem;
  line-height: 1.3;
}
.support p {
  margin: 0 0 8px;
  max-width: 64ch;
  color: var(--band-muted);
}

.support-links {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 0 24px;
}
.support-links a {
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  color: var(--band-link);
}

/* Footer */

.footer {
  background: var(--footer-bg);
  color: var(--footer-ink);
}
.footer-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 20px var(--gutter);
  font-size: 0.9375rem;
}
.footer-line { margin: 0; }

/* Small screens, motion, print */

@media (max-width: 40rem) {
  .support-inner { grid-template-columns: 1fr; }
  .support-logo { width: 61px; height: 56px; }
}

@media (prefers-reduced-motion: reduce) {
  .card { transition: none; }
}

@media print {
  .theme-toggle, .skip-link { display: none; }
  .masthead, .support, .footer { background: none; color: inherit; }
}