/* Shared style of explainer landing pages: an explanation page with a live anatomy figure and a video.
 * Fonts are local from video-kit/fonts (OFL), the palette is anatomy's light theme. */
@font-face { font-family: Serif; font-weight: 400; src: url(../video-kit/fonts/serif-400-cyr.woff2) format('woff2'); unicode-range: U+0400-045F; }
@font-face { font-family: Serif; font-weight: 400; src: url(../video-kit/fonts/serif-400-lat.woff2) format('woff2'); unicode-range: U+0000-00FF, U+2000-206F, U+2190-21FF, U+2212, U+2248; }
@font-face { font-family: Serif; font-weight: 400; font-style: italic; src: url(../video-kit/fonts/serif-400i-cyr.woff2) format('woff2'); unicode-range: U+0400-045F; }
@font-face { font-family: Serif; font-weight: 400; font-style: italic; src: url(../video-kit/fonts/serif-400i-lat.woff2) format('woff2'); unicode-range: U+0000-00FF, U+2000-206F; }
@font-face { font-family: Sans; font-weight: 400; src: url(../video-kit/fonts/golos-400-cyr.woff2) format('woff2'); unicode-range: U+0400-045F; }
@font-face { font-family: Sans; font-weight: 400; src: url(../video-kit/fonts/golos-400-lat.woff2) format('woff2'); unicode-range: U+0000-00FF, U+2000-206F, U+2190-21FF, U+2212; }
@font-face { font-family: Sans; font-weight: 600; src: url(../video-kit/fonts/golos-600-cyr.woff2) format('woff2'); unicode-range: U+0400-045F; }
@font-face { font-family: Sans; font-weight: 600; src: url(../video-kit/fonts/golos-600-lat.woff2) format('woff2'); unicode-range: U+0000-00FF, U+2000-206F, U+2190-21FF, U+2212; }
@font-face { font-family: Mono; font-weight: 400; src: url(../video-kit/fonts/mono-400-cyr.woff2) format('woff2'); unicode-range: U+0400-045F; }
@font-face { font-family: Mono; font-weight: 400; src: url(../video-kit/fonts/mono-400-lat.woff2) format('woff2'); unicode-range: U+0000-00FF, U+2000-206F, U+2190-21FF, U+2212; }

:root {
  --bg: #F2F2EF; --paper: #FBFBFA; --line: #E2E2DE; --ink: #18181A; --ink2: #3A3A3E; --muted: #6E6E73; --faint: #A6A6AA;
  --accent: #3E63DD; --accent-d: #2F4FB8; --accent-soft: #E3E9FB; --ok: #30A46C; --no: #E5484D;
}
* { box-sizing: border-box; }
html { color-scheme: light; }
body { margin: 0; background: var(--bg); color: var(--ink); font: 17px/1.6 Sans, system-ui, sans-serif; -webkit-font-smoothing: antialiased; }
a { color: var(--accent-d); }
.mono { font: 400 12.5px/1.2 Mono, ui-monospace, monospace; letter-spacing: .09em; text-transform: uppercase; }
.page { width: min(1080px, 100% - 32px); margin: 0 auto; padding: 28px 0 96px; }

/* header */
.top { display: flex; align-items: center; justify-content: space-between; gap: 16px; color: var(--muted); }
.top a { color: inherit; text-decoration: none; }
.top a:hover { color: var(--ink); }
.langs { display: flex; gap: 4px; }
.tools { display: flex; align-items: center; gap: 14px; }
.gh { display: inline-flex; align-items: center; gap: 7px; padding: 6px 10px; border-radius: 8px; color: var(--muted); }
.gh svg { width: 15px; height: 15px; }
.top a.gh:hover { color: var(--ink); background: var(--paper); }
.foot.src { margin-top: 10px; font-size: 13.5px; }
.langs button { border: 0; background: transparent; padding: 6px 10px; border-radius: 8px; font: inherit; color: var(--muted); cursor: pointer; }
.langs button[aria-pressed="true"] { background: var(--ink); color: var(--paper); }

/* hero */
.hero { padding: 56px 0 28px; max-width: 820px; }
.hero .eyebrow { color: var(--accent-d); }
.hero h1 { margin: 18px 0 0 -3px; font: 400 clamp(40px, 6.6vw, 76px)/1.02 Serif; letter-spacing: -.025em; }
.hero h1 em { color: var(--no); }
.hero .lede { margin: 22px 0 0; font-size: 19px; color: var(--ink2); max-width: 60ch; }
.questions { margin: 26px 0 0; padding: 0; list-style: none; display: flex; flex-wrap: wrap; gap: 8px; }
.questions li { padding: 7px 14px; border-radius: 999px; background: var(--paper); box-shadow: 0 0 0 1px var(--line); font-size: 15px; color: var(--ink2); }

/* sections */
section { margin-top: 26px; }
.sec-head { display: flex; gap: 14px; align-items: baseline; color: var(--faint); }
.sec-head .n { color: var(--accent); }
h2 { margin: 8px 0 12px; font: 400 clamp(28px, 3.6vw, 40px)/1.12 Serif; letter-spacing: -.012em; }
.sub { margin: 0 0 18px; color: var(--muted); max-width: 64ch; }

/* figure: an anatomy card with buttons */
.iso-figure { margin: 0; }
.iso-plate { padding: 52px 18px 56px; }
.controls { display: flex; flex-wrap: wrap; gap: 10px 18px; align-items: center; margin-top: 14px; }
.btn { border: 0; border-radius: 12px; padding: 11px 18px; font: 600 15px Sans, sans-serif; cursor: pointer; background: var(--ink); color: var(--paper); }
.btn.ghost { background: var(--paper); color: var(--ink); box-shadow: 0 0 0 1.5px var(--line); }
.btn:hover { filter: brightness(1.12); }
.btn kbd { margin-left: 8px; padding: 1px 6px; border-radius: 5px; background: rgba(255, 255, 255, .16); font: 400 12px Mono, monospace; }
.btn.ghost kbd { background: var(--bg); }
.seg { display: inline-flex; align-items: center; gap: 4px; padding: 4px; border-radius: 12px; background: var(--paper); box-shadow: 0 0 0 1.5px var(--line); }
.seg span { padding: 0 8px; color: var(--muted); font-size: 14px; }
.seg button { border: 0; padding: 7px 12px; border-radius: 9px; background: transparent; font: 500 14px Sans, sans-serif; cursor: pointer; color: var(--ink2); }
.seg button[aria-pressed="true"] { background: var(--ink); color: var(--paper); }
.meter { display: grid; grid-template-columns: repeat(3, 1fr); gap: 10px; margin-top: 14px; }
.meter div { padding: 14px 16px; border-radius: 14px; background: var(--paper); box-shadow: 0 0 0 1px var(--line); }
.meter b { display: block; font: 600 34px/1 Sans, sans-serif; font-variant-numeric: tabular-nums; }
.meter span { color: var(--muted); font-size: 13.5px; }
.meter .m-ok b { color: var(--ok); }
.meter .m-no b { color: var(--no); }
.iso-stage:focus-visible { outline: 1px solid var(--muted); outline-offset: 6px; }

/* video */
.video { position: relative; border-radius: 18px; overflow: hidden; background: #0B1222; box-shadow: 0 30px 60px -30px rgba(24, 24, 26, .35); }
.video video, .video iframe { display: block; width: 100%; aspect-ratio: 16 / 9; border: 0; background: #0B1222; }
.video.v { max-width: 420px; margin: 0 auto; }
.video.v video, .video.v iframe { aspect-ratio: 9 / 16; }
.vtabs { display: flex; flex-wrap: wrap; gap: 10px; margin: 0 0 14px; }
.chapters { display: grid; grid-template-columns: repeat(auto-fill, minmax(190px, 1fr)); gap: 8px; margin-top: 14px; padding: 0; list-style: none; }
.chapters button { width: 100%; text-align: left; border: 0; border-radius: 12px; padding: 10px 14px; background: var(--paper); box-shadow: 0 0 0 1px var(--line); font: 500 14.5px Sans, sans-serif; color: var(--ink2); cursor: pointer; }
.chapters button .mono { display: block; margin-bottom: 4px; color: var(--accent); }

/* explanation */
.facts { display: grid; grid-template-columns: repeat(auto-fit, minmax(240px, 1fr)); gap: 12px; }
.fact { padding: 22px 22px 20px; border-radius: 18px; background: var(--paper); box-shadow: 0 0 0 1px var(--line); }
.fact .mono { color: var(--accent); }
.fact h3 { margin: 10px 0 6px; font: 400 25px/1.15 Serif; }
.fact p { margin: 0; color: var(--ink2); font-size: 15.5px; }
.formula { margin: 16px 0 0; padding: 22px 26px; border-radius: 18px; background: var(--ink); color: #fff; font: 400 clamp(24px, 3.4vw, 36px)/1.2 Serif; }
.formula b { font-weight: 400; font-style: italic; color: #9DB2F5; }
.formula small { display: block; margin-top: 8px; font: 400 14.5px/1.5 Sans, sans-serif; color: #B9B9BE; }
pre { margin: 0; padding: 22px 24px; border-radius: 18px; background: #16161A; color: #E8E8EA; font: 400 14px/1.6 Mono, ui-monospace, monospace; overflow: auto; }
pre .c { color: #8A8A92; }
pre .k { color: #9DB2F5; }
.foot { margin-top: 48px; color: var(--muted); font-size: 14.5px; }

@media (max-width: 640px) {
  .meter b { font-size: 26px; }
  .iso-plate { padding: 44px 6px 56px; }
}

/* language switch (links) and the "this page is available in …" banner */
.langs a { padding: 6px 10px; border-radius: 8px; color: var(--muted); text-decoration: none; }
.langs a:hover { color: var(--ink); }
.langs a[aria-current="page"] { background: var(--ink); color: var(--paper); }
.suggest { display: flex; align-items: center; gap: 14px; min-height: 44px; padding: 6px max(16px, calc((100% - 1080px) / 2)); background: var(--ink); color: #ecebe4; font-size: 14px; }
.suggest span { flex: 1; }
.suggest a { color: #9DB2F5; font-weight: 600; }
.suggest button { background: none; border: 0; color: inherit; font-size: 20px; line-height: 1; cursor: pointer; padding: 4px 8px; opacity: .7; }
.suggest button:hover { opacity: 1; }
.video[hidden] { display: none; }

/* catalog: topic cards */
.cards { display: grid; grid-template-columns: repeat(auto-fill, minmax(320px, 1fr)); gap: 16px; margin-top: 18px; }
.card { display: block; border-radius: 20px; overflow: hidden; background: var(--paper); box-shadow: 0 0 0 1px var(--line); color: inherit; text-decoration: none; transition: transform .2s; }
.card:hover { transform: translateY(-3px); }
.card img { display: block; width: 100%; aspect-ratio: 16 / 9; object-fit: cover; background: var(--bg); }
.card div { padding: 18px 20px 20px; }
.card .mono { color: var(--accent); }
.card h3 { margin: 8px 0 6px; font: 400 26px/1.15 Serif; }
.card p { margin: 0; color: var(--muted); font-size: 15px; }
.hero h1 em { font-style: normal; }
.catalog .hero h1 em { color: var(--accent); }