/* A neutral reading surface with system typography and compact image/text sections. */
:root {
  color-scheme: light;
  --paper: #fafafa;
  --ink: #1d1d1f;
  --muted: #646469;
  --line: #dedee3;
  --accent: #005fc5;
  --panel: #f0f0f3;
  --font: -apple-system, BlinkMacSystemFont, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", system-ui, sans-serif;
  font: 17px/1.8 var(--font);
  color: var(--ink);
  background: var(--paper);
  scroll-padding-top: 7rem;
}
* { box-sizing: border-box; }
body { margin: 0; }
::selection { color: var(--paper); background: var(--accent); }
a { color: var(--accent); text-underline-offset: .2em; text-decoration-thickness: 1px; }
a:hover { text-decoration-thickness: 2px; }
button { font: inherit; cursor: pointer; }
:focus-visible { outline: 3px solid var(--accent); outline-offset: 5px; }
img { display: block; max-width: 100%; height: auto; }
.wrap { width: min(1120px, calc(100% - 80px)); margin-inline: auto; }
.skip { position: absolute; top: -100px; left: 24px; z-index: 3; padding: 8px 16px; background: var(--paper); }
.skip:focus { top: 12px; }
.site-header { border-bottom: 1px solid var(--line); }
.site-header .wrap { min-height: 88px; display: flex; align-items: center; gap: 32px; }
.wordmark { color: var(--ink); text-decoration: none; font-size: 23px; font-weight: 750; }
.header-links { display: flex; align-items: center; gap: 28px; margin-left: auto; }
.header-links a { color: var(--ink); text-decoration: none; }
.header-links a:hover { color: var(--accent); }
.languages { display: flex; gap: 16px; padding-left: 28px; border-left: 1px solid var(--line); }
.languages [aria-current] { color: var(--accent); text-decoration: underline; text-decoration-thickness: 2px; }
.overview { display: grid; grid-template-columns: minmax(0, 1.5fr) minmax(0, 1fr); align-items: center; gap: 72px; padding-block: 64px 56px; }
h1, h2, h3 { line-height: 1.25; text-wrap: balance; }
h1 { margin: 0 0 20px; font-size: clamp(44px, 5vw, 68px); letter-spacing: -.035em; font-weight: 750; }
h2 { margin: 0 0 24px; font-size: clamp(25px, 2.6vw, 32px); letter-spacing: -.02em; }
h2 a { display: inline-block; font-size: 16px; font-weight: 500; margin-left: 12px; letter-spacing: normal; vertical-align: middle; }
.intro h2 { font-size: clamp(22px, 2.2vw, 28px); margin-bottom: 28px; }
p { max-width: 70ch; margin: 0 0 16px; }
.intro p:last-child { margin-bottom: 0; }
.cover { margin: 0; }
.cover img { width: 100%; border-radius: 12px; }
.section-nav { display: flex; flex-wrap: wrap; column-gap: 32px; row-gap: 8px; padding-block: 20px; border-block: 1px solid var(--line); }
.section-nav a { color: var(--ink); text-decoration: none; }
.section-nav a:hover { color: var(--accent); text-decoration: underline; }
.readme-section, .videos { padding-block: 56px; }
.readme-section { border-bottom: 1px solid var(--line); }
.gallery { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); column-gap: 24px; row-gap: 32px; }
.gallery figure { margin: 0; min-width: 0; }
.gallery img { width: 100%; border-radius: 10px; }
.gallery figcaption { margin-top: 10px; font-size: 16px; font-weight: 600; }
.gallery strong { font-weight: inherit; }
.feature-row { display: grid; grid-template-columns: minmax(0, 1fr) minmax(0, 1.35fr); align-items: center; gap: 64px; }
.feature-copy { min-width: 0; }
.feature-copy h2 { margin-bottom: 24px; }
.feature-copy h2 a { display: block; margin: 12px 0 0; }
.feature-copy p { line-height: 1.7; }
.project-stack { margin: -8px 0 24px; color: var(--muted); font-size: 15px; }
.feature-media { margin: 0; min-width: 0; }
.feature-media img { width: 100%; border-radius: 12px; }
#portal { grid-template-columns: minmax(0, 1.35fr) minmax(0, 1fr); }
#portal .feature-copy { grid-column: 2; grid-row: 1; }
#portal .feature-media { grid-column: 1; grid-row: 1; }
.readme-section code { padding: 3px 7px; border: 1px solid var(--line); border-radius: 5px; background: var(--panel); font-size: .9em; overflow-wrap: anywhere; }
.video-list { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 32px; }
.video-item { margin: 0; min-width: 0; }
.video-player { position: relative; width: 100%; aspect-ratio: 16 / 10; background: #1d1d1f; overflow: hidden; border-radius: 12px; }
.video-player > img { width: 100%; height: 100%; object-fit: cover; object-position: 50% 42%; opacity: .82; }
.video-player iframe { position: absolute; inset: 0; width: 100%; height: 100%; border: 0; background: #1d1d1f; }
.video-load { position: absolute; inset: 0; width: 100%; display: grid; place-items: center; border: 0; color: var(--ink); text-decoration: none; background: transparent; padding: 24px; }
.video-load span { display: inline-flex; align-items: center; gap: 10px; padding: 12px 20px; border: 1px solid #e5e5ea; border-radius: 10px; background: #fff; box-shadow: 0 8px 24px rgb(0 0 0 / .16); font-size: 16px; font-weight: 600; }
.video-load:hover span { background: #ededf0; }
.video-load:focus-visible { outline-offset: -7px; outline-color: #fff; }
@media (max-width: 900px) {
  .wrap { width: calc(100% - 48px); }
  .overview { gap: 32px; padding-top: 48px; }
  .gallery { gap: 24px 16px; }
  .feature-row, #portal { gap: 32px; }
}
@media (max-width: 760px) {
  .feature-row, #portal { grid-template-columns: 1fr; gap: 28px; }
  #portal .feature-copy, #portal .feature-media { grid-column: auto; grid-row: auto; }
}
@media (max-width: 640px) {
  :root { font-size: 16px; scroll-padding-top: 24px; }
  .wrap { width: calc(100% - 40px); }
  .site-header .wrap { min-height: 76px; gap: 12px; flex-wrap: wrap; padding-block: 16px; }
  .wordmark { font-size: 21px; }
  .header-links { gap: 16px; font-size: 14px; }
  .header-home { display: none; }
  .languages { padding-left: 16px; gap: 12px; }
  .overview { grid-template-columns: 1fr; padding-block: 40px 32px; gap: 32px; }
  h1 { font-size: 48px; margin-bottom: 16px; }
  .intro h2 { margin-bottom: 24px; }
  .cover { width: min(360px, 100%); margin-inline: auto; }
  .section-nav { gap: 8px 24px; font-size: 15px; }
  .readme-section, .videos { padding-block: 36px; }
  h2 { font-size: 26px; }
  h2 a { display: block; margin: 10px 0 0; font-size: 15px; }
  .gallery { grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 24px 16px; }
  .gallery figcaption { font-size: 14px; }
  .video-list { grid-template-columns: 1fr; gap: 28px; }
  .video-player { aspect-ratio: 4 / 3; }
}