/* Kety landing page.
   Plain CSS, no build step, no external request of any kind — no webfont, no
   script, no analytics. Palette and type carried over from the previous site
   (frontend/src/index.css and App.css on the private repo's main branch). */

:root {
  --bg: linear-gradient(165deg, #fff5f9 0%, #f0f7ff 42%, #e8f0ff 100%);
  --text: #1c1c1e;
  --text-soft: #4a4a52;
  --text-faint: #6b6b76;
  --accent: #007aff;
  --accent-deep: #0056c8;
  --rule: rgba(28, 28, 30, 0.1);
  --panel: rgba(255, 255, 255, 0.62);
  --panel-rule: rgba(28, 28, 30, 0.08);
  --shadow: 0 8px 30px rgba(28, 28, 60, 0.08);
  --brand-gradient: linear-gradient(120deg, #1c1c1e 0%, #5c3d5a 45%, #c45b7a 100%);
  --content: 58rem;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: linear-gradient(165deg, #14141c 0%, #1a1f2e 50%, #121820 100%);
    --text: rgba(255, 255, 255, 0.92);
    --text-soft: rgba(255, 255, 255, 0.74);
    --text-faint: rgba(255, 255, 255, 0.58);
    --accent: #0a84ff;
    --accent-deep: #0066dd;
    --rule: rgba(255, 255, 255, 0.12);
    --panel: rgba(255, 255, 255, 0.05);
    --panel-rule: rgba(255, 255, 255, 0.1);
    --shadow: 0 8px 30px rgba(0, 0, 0, 0.35);
    --brand-gradient: linear-gradient(
      120deg,
      rgba(255, 255, 255, 0.95) 0%,
      #ffd6e8 55%,
      #e8a0b8 100%
    );
  }
}

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

html {
  font-family:
    -apple-system, BlinkMacSystemFont, "SF Pro Display", "SF Pro Text",
    "Segoe UI", "Helvetica Neue", Arial, sans-serif;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  -webkit-text-size-adjust: 100%;
}

body {
  margin: 0;
  min-height: 100vh;
  color: var(--text);
  background: var(--bg);
  background-attachment: fixed;
  display: flex;
  flex-direction: column;
}

main {
  flex: 1 0 auto;
}

.wrap {
  width: 100%;
  max-width: var(--content);
  margin: 0 auto;
  padding-left: 1.35rem;
  padding-right: 1.35rem;
}

html {
  scroll-behavior: smooth;
}

/* Jumped-to sections keep a little air above them instead of sitting on the viewport edge. */
[id] {
  scroll-margin-top: 2rem;
}

a {
  color: var(--accent);
  text-decoration-thickness: 1px;
  text-underline-offset: 2px;
}

a:hover {
  color: var(--accent-deep);
}

/* An aside, not a destination: it stays in the body colour so the sentence reads
   straight through, and earns its underline by being italic rather than blue. */
.aside-link {
  color: inherit;
  font-style: italic;
  text-decoration: underline;
  text-decoration-thickness: 1px;
  text-underline-offset: 2px;
  opacity: 0.75;
}

.aside-link:hover {
  color: inherit;
  opacity: 1;
}

/* ── Header ─────────────────────────────────────────────── */

.site-header {
  border-bottom: 1px solid var(--rule);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding-top: 0.9rem;
  padding-bottom: 0.9rem;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 0.55rem;
  line-height: 1;
}

.brand-icon {
  display: block;
  width: 32px;
  height: 32px;
}

.brand-name {
  font-size: 1.2rem;
  font-weight: 700;
  letter-spacing: -0.03em;
  background: var(--brand-gradient);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

.header-link {
  font-size: 0.9rem;
  font-weight: 500;
  text-decoration: none;
}

.header-link:hover {
  text-decoration: underline;
}

/* ── Hero ───────────────────────────────────────────────── */

.hero {
  padding-top: 3.4rem;
  padding-bottom: 1rem;
}

h1 {
  margin: 0 0 1.1rem;
  font-size: clamp(1.75rem, 5.2vw, 2.4rem);
  font-weight: 700;
  line-height: 1.16;
  letter-spacing: -0.032em;
  /* Wide enough for the first line of the title to stay whole; the break before
     "on open source models" is explicit in the markup. */
  max-width: 48ch;
}

.lead {
  margin: 0;
  font-size: 1.08rem;
  color: var(--text-soft);
  max-width: 48rem;
}

/* ── Download ───────────────────────────────────────────── */

.download {
  margin-top: 2.1rem;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.9rem 1.1rem;
}

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.72rem 1.35rem;
  border-radius: 10px;
  font-size: 1rem;
  font-weight: 600;
  text-decoration: none;
  color: #fff;
  background: linear-gradient(165deg, #007aff 0%, #0056c8 100%);
  box-shadow: 0 2px 10px rgba(0, 122, 255, 0.28);
  transition: box-shadow 0.15s, transform 0.12s;
}

.button:hover {
  color: #fff;
  box-shadow: 0 4px 16px rgba(0, 122, 255, 0.38);
}

.button:active {
  transform: scale(0.98);
}

@media (prefers-color-scheme: dark) {
  .button {
    background: linear-gradient(165deg, #0a84ff 0%, #0066dd 100%);
    box-shadow: 0 2px 10px rgba(10, 132, 255, 0.25);
  }
}

.download-meta {
  margin: 0;
  font-size: 0.94rem;
  color: var(--text-faint);
}

.download-meta strong {
  color: var(--text-soft);
  font-weight: 600;
}

/* A footnote to the download button, not a warning box: it is worth saying, and not
   worth a panel of its own. */
.notice {
  margin-top: 0.85rem;
  max-width: 44rem;
  font-size: 0.82rem;
  font-style: italic;
  line-height: 1.55;
  color: var(--text-soft);
  opacity: 0.85;
}

.notice b {
  color: var(--text);
  font-weight: 600;
}

.section-intro {
  margin: 0 0 1.6rem;
  max-width: 46rem;
  color: var(--text-soft);
}

/* ── Screenshots ────────────────────────────────────────── */

.shot-block {
  padding-top: 3rem;
  padding-bottom: 0.4rem;
}

.shot {
  margin: 0;
}

.shot img {
  display: block;
  width: 100%;
  height: auto;
  border: 1px solid var(--panel-rule);
  border-radius: 14px;
  box-shadow: var(--shadow);
}

.shot figcaption {
  margin-top: 0.7rem;
  font-size: 0.9rem;
  color: var(--text-faint);
}

/* ── Sections ───────────────────────────────────────────── */

.section-title {
  margin: 0 0 1.6rem;
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--text-faint);
}

.points {
  padding-top: 3.4rem;
}

.point + .point {
  margin-top: 2.2rem;
  padding-top: 2.2rem;
  border-top: 1px solid var(--rule);
}

.point h3 {
  margin: 0 0 0.5rem;
  font-size: 1.16rem;
  font-weight: 650;
  letter-spacing: -0.02em;
}

.point p {
  margin: 0;
  color: var(--text-soft);
}

.point p + p {
  margin-top: 0.85rem;
}

.closing {
  padding-top: 3.4rem;
  padding-bottom: 3.4rem;
}

.closing p {
  margin: 0;
  color: var(--text-soft);
}

.closing p + p {
  margin-top: 0.85rem;
}

/* ── Footer ─────────────────────────────────────────────── */

.site-footer {
  border-top: 1px solid var(--rule);
  font-size: 0.9rem;
  color: var(--text-faint);
}

.footer-inner {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  justify-content: space-between;
  gap: 0.4rem 1.2rem;
  padding-top: 1.5rem;
  padding-bottom: 2.5rem;
}

.footer-inner p {
  margin: 0;
}

/* ── Small screens ──────────────────────────────────────── */

@media (max-width: 34rem) {
  .hero {
    padding-top: 2.4rem;
  }

  h1 {
    max-width: none;
  }

  .download {
    align-items: flex-start;
    flex-direction: column;
    gap: 0.8rem;
  }

  .button {
    width: 100%;
  }

  .shot-block,
  .points,
  .closing {
    padding-top: 2.6rem;
  }
}

@media (prefers-reduced-motion: reduce) {
  * {
    transition: none !important;
  }
}