/* Fravilabs design system: tokens + components.
   Source of truth: the "Fravilabs" design system in Claude Design. */

@font-face { font-family: "Albert Sans"; src: url("/assets/fonts/AlbertSans-latin-wght.woff2") format("woff2"); font-weight: 100 900; font-style: normal; font-display: swap; }
@font-face { font-family: "IBM Plex Sans"; src: url("/assets/fonts/IBMPlexSans-latin-wght.woff2") format("woff2"); font-weight: 100 700; font-style: normal; font-display: swap; }

/* ---------- tokens ---------- */
:root {
  --surface: #FCFBFF; --surface-raised: #FFFFFF; --surface-tint: #EFEAFF;
  --line: #E6E1F5; --line-strong: #8D87A3;
  --ink: #222222; --ink-muted: #5E5A6B;
  --violet: #7C5CFF; --violet-accent: #7C5CFF; --violet-deep: #5B3FD9;
  --action: #5B3FD9; --action-hover: #4A2FC4; --on-action: #FFFFFF;
  --focus: var(--action); --bolt: #FFFFFF; --device: #222222;
  --shadow-float: 0 1px 2px rgba(34,34,34,0.06), 0 16px 40px rgba(91,63,217,0.14);
  --show-light: revert; --show-dark: none;

  --space-1: 4px; --space-2: 8px; --space-3: 12px; --space-4: 16px; --space-5: 24px;
  --space-6: 32px; --space-7: 48px; --space-8: 64px; --space-9: 96px; --space-10: 144px;
  --radius-sm: 8px; --radius-md: 14px; --radius-lg: 24px; --radius-device: 44px; --radius-pill: 999px;
  --container: 1120px; --measure: 64ch; --header-height: 72px;
  --font-display: "Albert Sans", ui-sans-serif, system-ui, -apple-system, sans-serif;
  --font-text: "IBM Plex Sans", ui-sans-serif, system-ui, -apple-system, sans-serif;
  color-scheme: light;
}
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --surface: #110E1C; --surface-raised: #1B1530; --surface-tint: #231B40;
    --line: #2C2447; --line-strong: #6E6589;
    --ink: #F2EFFF; --ink-muted: #A9A3C2;
    --violet-accent: #9D88FF; --violet-deep: #6A4DF0;
    --action: #9D88FF; --action-hover: #B3A3FF; --on-action: #110E1C; --device: #05040A;
    --shadow-float: 0 1px 2px rgba(0,0,0,0.4), 0 20px 48px rgba(0,0,0,0.55);
    --show-light: none; --show-dark: revert;
    color-scheme: dark;
  }
}
:root[data-theme="dark"] {
  --surface: #110E1C; --surface-raised: #1B1530; --surface-tint: #231B40;
  --line: #2C2447; --line-strong: #6E6589;
  --ink: #F2EFFF; --ink-muted: #A9A3C2;
  --violet-accent: #9D88FF; --violet-deep: #6A4DF0;
  --action: #9D88FF; --action-hover: #B3A3FF; --on-action: #110E1C; --device: #05040A;
  --shadow-float: 0 1px 2px rgba(0,0,0,0.4), 0 20px 48px rgba(0,0,0,0.55);
  --show-light: none; --show-dark: revert;
  color-scheme: dark;
}

/* ---------- base ---------- */
html { scroll-behavior: smooth; scroll-padding-top: var(--space-6); }
body { margin: 0; background: var(--surface); color: var(--ink); }
.fl, .fl * { box-sizing: border-box; }
.fl { font-family: var(--font-text); color: var(--ink); -webkit-font-smoothing: antialiased; }
.fl-only-light { display: var(--show-light) !important; }
.fl-only-dark { display: var(--show-dark) !important; }
.fl-container { max-width: var(--container); margin: 0 auto; padding: 0 var(--space-6); }
@media (max-width: 720px) { .fl-container { padding: 0 var(--space-4); } }
.fl-muted { color: var(--ink-muted); }
.fl-accent { color: var(--violet-accent); }
.fl-tnum { font-variant-numeric: tabular-nums; }
.fl-sr { position: absolute; width: 1px; height: 1px; overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap; }
.fl :focus-visible { outline: 2px solid var(--focus); outline-offset: 2px; }

/* ---------- Button ---------- */
.fl-btn { display: inline-flex; align-items: center; justify-content: center; gap: var(--space-2);
  font: 700 16px/20px var(--font-display); letter-spacing: 0; text-decoration: none; white-space: nowrap;
  height: 48px; padding: 0 var(--space-5); border-radius: var(--radius-pill); border: 1px solid transparent;
  cursor: pointer; transition: background-color .18s ease-out, border-color .18s ease-out, color .18s ease-out; }
.fl-btn-sm { height: 40px; padding: 0 var(--space-4); font-size: 15px; }
.fl-btn-primary { background: var(--action); color: var(--on-action); }
.fl-btn-primary:hover { background: var(--action-hover); }
.fl-btn-secondary { background: transparent; color: var(--ink); border-color: var(--line-strong); }
.fl-btn-secondary:hover { border-color: var(--ink); }
.fl-btn-ghost { background: transparent; color: var(--action); padding: 0 var(--space-2); }
.fl-btn-ghost:hover { text-decoration: underline; text-underline-offset: 3px; }

/* ---------- TextLink ---------- */
.fl-link { color: var(--action); font-weight: 700; text-decoration: none; }
.fl-link:hover { color: var(--action-hover); text-decoration: underline; text-underline-offset: 3px; }
.fl-link-arrow { display: inline-block; margin-left: .25em; transition: transform .18s ease-out; }
.fl-link:hover .fl-link-arrow { transform: translateX(2px); }

/* ---------- SectionHeader ---------- */
.fl-section-head { max-width: 720px; }
.fl-label { font: 500 15px/20px var(--font-text); letter-spacing: .005em; color: var(--ink); margin: 0 0 var(--space-3); }
.fl-label b { color: var(--action); font-weight: 500; font-variant-numeric: tabular-nums; }
.fl-h2 { font: 700 32px/38px var(--font-display); letter-spacing: -.015em; margin: 0; }
.fl-lead { font: 400 21px/32px var(--font-text); color: var(--ink-muted); margin: var(--space-4) 0 0; max-width: var(--measure); }

/* ---------- SiteHeader ---------- */
.fl-header { height: var(--header-height); display: flex; align-items: center; justify-content: space-between; gap: var(--space-5); }
.fl-header-logo { display: block; line-height: 0; }
.fl-header-logo img { height: 28px; width: auto; }
.fl-nav { display: flex; align-items: center; gap: var(--space-5); }
.fl-nav a:not(.fl-btn) { color: var(--ink-muted); font: 700 15px/20px var(--font-display); text-decoration: none; }
.fl-nav a:not(.fl-btn):hover, .fl-nav a[aria-current="page"] { color: var(--ink); }
@media (max-width: 720px) { .fl-nav .fl-nav-links { display: none; } }

/* ---------- LangToggle ---------- */
.fl-lang { display: inline-flex; padding: 3px; border: 1px solid var(--line-strong); border-radius: var(--radius-pill); }
.fl-lang button { font: 700 13px/16px var(--font-display); letter-spacing: .04em; border: 0; background: transparent; color: var(--ink-muted);
  height: 26px; min-width: 36px; padding: 0 var(--space-2); border-radius: var(--radius-pill); cursor: pointer;
  transition: background-color .18s ease-out, color .18s ease-out; }
.fl-lang button[aria-pressed="true"] { background: var(--ink); color: var(--surface); }

/* ---------- PhoneFrame ---------- */
.fl-phone { position: relative; width: 280px; aspect-ratio: 1206 / 2622; padding: 10px; border-radius: var(--radius-device);
  background: var(--device); box-shadow: var(--shadow-float); flex: none; }
.fl-phone img { display: block; width: 100%; height: 100%; object-fit: cover; border-radius: calc(var(--radius-device) - 10px); }
.fl-phone-sm { width: 200px; padding: 7px; }
.fl-phone-sm img { border-radius: calc(var(--radius-device) - 14px); }
.fl-phone-caption { font: 400 14px/21px var(--font-text); color: var(--ink-muted); margin-top: var(--space-4); text-align: center; }

/* ---------- ExperimentCard ---------- */
.fl-card { border: 1px solid var(--line); border-radius: var(--radius-lg); background: var(--surface-raised); padding: var(--space-6);
  display: grid; gap: var(--space-5); }
.fl-card-meta { display: flex; align-items: center; justify-content: space-between; gap: var(--space-3); }
.fl-exp { font: 500 15px/20px var(--font-text); letter-spacing: .005em; font-variant-numeric: tabular-nums; color: var(--ink); }
.fl-card-title { font: 700 44px/48px var(--font-display); letter-spacing: -.02em; margin: 0; }
.fl-card-alt { font: 400 17px/27px var(--font-text); color: var(--ink-muted); margin: var(--space-1) 0 0; }
.fl-card-body { font: 400 17px/27px var(--font-text); margin: 0; max-width: var(--measure); }
.fl-card-list { list-style: none; margin: 0; padding: 0; display: grid; gap: var(--space-2); }
.fl-card-list li { font: 400 17px/27px var(--font-text); padding-left: var(--space-5); position: relative; }
.fl-card-list li::before { content: ""; position: absolute; left: 2px; top: 10px; width: 8px; height: 8px; border-radius: var(--radius-pill); background: var(--violet); }
.fl-card-actions { display: flex; flex-wrap: wrap; align-items: center; gap: var(--space-3) var(--space-5); }
.fl-card-feature { grid-template-columns: 1fr auto; column-gap: var(--space-8); align-items: center; padding: var(--space-8); }
.fl-card-feature .fl-card-main { display: grid; gap: var(--space-5); align-content: start; }
.fl-card-quiet { background: transparent; border-style: dashed; border-color: var(--line-strong); }
.fl-card-quiet .fl-card-title { font-size: 22px; line-height: 28px; letter-spacing: -.01em; }
@media (max-width: 860px) {
  .fl-card-feature { grid-template-columns: 1fr; padding: var(--space-5); row-gap: var(--space-7); }
  .fl-card-feature .fl-phone { justify-self: center; }
  .fl-card { padding: var(--space-5); }
  .fl-card-title { font-size: 36px; line-height: 40px; }
}

/* ---------- Principle ---------- */
.fl-principle { display: grid; grid-template-columns: 48px 1fr; gap: var(--space-4); padding: var(--space-5) 0; border-top: 1px solid var(--line); }
.fl-principle-n { font: 500 15px/28px var(--font-text); font-variant-numeric: tabular-nums; color: var(--action); }
.fl-principle h3 { font: 700 22px/28px var(--font-display); letter-spacing: -.01em; margin: 0; }
.fl-principle p { font: 400 17px/27px var(--font-text); color: var(--ink-muted); margin: var(--space-2) 0 0; max-width: var(--measure); }

/* ---------- FillGauge: the tube, as an abstract level ---------- */
.fl-gauge { display: inline-block; position: relative; width: 10px; height: 20px; flex: none;
  border-radius: var(--radius-pill); box-shadow: inset 0 0 0 1.5px var(--ink); overflow: hidden; vertical-align: middle; }
.fl-gauge > i { position: absolute; left: 3px; right: 3px; bottom: 3px; height: 14px; border-radius: var(--radius-pill); background: var(--violet);
  transition: height .24s ease-out; }

/* ---------- KeyPoints ---------- */
.fl-keypoints { background: var(--surface-tint); border-radius: var(--radius-md); padding: var(--space-5); }
.fl-keypoints h3 { font: 500 15px/20px var(--font-text); letter-spacing: .005em; color: var(--ink); margin: 0 0 var(--space-3); }
.fl-keypoints ul { list-style: none; margin: 0; padding: 0; display: grid; gap: var(--space-2); }
.fl-keypoints li { display: grid; grid-template-columns: 20px 1fr; gap: var(--space-3); font: 600 17px/27px var(--font-text); }
.fl-keypoints li .fl-gauge { margin-top: 4px; }

/* ---------- SiteFooter ---------- */
.fl-footer { border-top: 1px solid var(--line); padding: var(--space-6) 0; display: flex; flex-wrap: wrap; align-items: center; justify-content: space-between; gap: var(--space-4);
  font: 400 14px/21px var(--font-text); color: var(--ink-muted); }
.fl-footer-id { display: flex; align-items: center; gap: var(--space-3); }
.fl-footer-id img { width: 24px; height: 24px; }
.fl-footer nav { display: flex; flex-wrap: wrap; gap: var(--space-2) var(--space-5); }
.fl-footer a { color: var(--ink-muted); text-decoration: none; }
.fl-footer a:hover { color: var(--ink); text-decoration: underline; text-underline-offset: 3px; }

@media (prefers-reduced-motion: reduce) { html { scroll-behavior: auto; } .fl * { transition: none !important; } }
@media (max-width: 520px) { .fl-nav > .fl-btn { display: none; } .fl-header-logo img { height: 24px; } }