/* youtube-courses: shared tokens copied from alozanoroble.github.io/styles.css */
/* Tokens shared with alozanoroble.github.io/articles */
:root {
  --paper: #FCFBF8; --raised: #F4F3EE; --ink: #171B22; --muted: #5A6170;
  --rule: #DEDCD5; --accent: #0E6E68; --accent-soft: #E0EEEC;
  --pre: #8A5A16; --pre-soft: #F6EEE0;
  --serif: 'Spectral', Georgia, 'Times New Roman', serif;
  --sans: 'Source Sans 3', system-ui, -apple-system, 'Segoe UI', sans-serif;
  --mono: 'IBM Plex Mono', ui-monospace, SFMono-Regular, Menlo, monospace;
  color-scheme: light dark;
}
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --paper: #12151A; --raised: #191D24; --ink: #E6E9EC; --muted: #9AA3AE;
    --rule: #272D36; --accent: #57C1B8; --accent-soft: #12312F;
    --pre: #D9A441; --pre-soft: #2A2113;
  }
}
:root[data-theme="dark"] {
  --paper: #12151A; --raised: #191D24; --ink: #E6E9EC; --muted: #9AA3AE;
  --rule: #272D36; --accent: #57C1B8; --accent-soft: #12312F;
  --pre: #D9A441; --pre-soft: #2A2113;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0; background: var(--paper); color: var(--ink);
  font: 400 1.0625rem/1.6 var(--sans);
  -webkit-font-smoothing: antialiased;
}
a { color: var(--accent); text-decoration: none; text-underline-offset: 0.18em; }
a:hover { text-decoration: underline; }
.btn:hover, .feature:hover, .thumb:hover, .brand:hover, nav a:hover, .app h3 a:hover { text-decoration: none; }
em { font-style: italic; }

.wrap { max-width: 68rem; margin: 0 auto; padding: 0 16px; }
@media (min-width: 720px) { .wrap { padding: 0 32px; } }


.wrap { max-width: 68rem; margin: 0 auto; padding: 0 16px; }
@media (min-width: 720px) { .wrap { padding: 0 32px; } }
.kicker { font: 500 0.8rem var(--mono); letter-spacing: 0.06em; text-transform: uppercase; color: var(--accent); margin: 0 0 0.75rem; }
h1 { font: 500 clamp(2.2rem, 5.5vw, 3.4rem)/1.08 var(--serif); margin: 0 0 1.25rem; letter-spacing: -0.01em; }
h2 { font: 500 1.75rem var(--serif); margin: 0 0 1.25rem; }
.lede { font: 400 1.3rem/1.5 var(--serif); margin-top: 0; }
.section-note { color: var(--muted); }
.foot { border-top: 1px solid var(--rule); margin-top: 2rem; padding-top: 1rem; padding-bottom: 2.5rem; color: var(--muted); font-size: 0.9rem; }

.sr-only { position: absolute; width: 1px; height: 1px; overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap; }

.c-hero { padding: 3.5rem 0 1.5rem; max-width: 46rem; }
@media (min-width: 880px) { .c-hero { padding-top: 4.5rem; } }
.c-stats { font: 500 0.85rem var(--mono); color: var(--muted); margin-top: 1rem; }

.c-tools { display: flex; flex-wrap: wrap; gap: 0.75rem 1.25rem; align-items: center; justify-content: space-between;
  padding: 1rem 0 0.5rem; border-top: 1px solid var(--rule); }
.chips { display: flex; flex-wrap: wrap; gap: 0.5rem; }
.chip { font: 500 0.92rem var(--sans); color: var(--muted); background: var(--paper); border: 1px solid var(--rule);
  border-radius: 999px; padding: 0.3rem 0.9rem; cursor: pointer; }
.chip:hover { color: var(--accent); border-color: var(--accent); }
.chip[aria-selected="true"] { background: var(--accent); border-color: var(--accent); color: var(--paper); }
.search input { font: 400 0.95rem var(--sans); color: var(--ink); background: var(--paper); border: 1px solid var(--rule);
  border-radius: 6px; padding: 0.45rem 0.75rem; width: min(20rem, 100%); }
.search { flex: 0 1 20rem; }
.search input { width: 100%; }
.search input:focus { outline: 2px solid var(--accent); outline-offset: 1px; border-color: var(--accent); }

.c-group { padding-top: 2rem; }
.c-group h2 { margin-bottom: 0.6rem; }
.c-group .section-note { margin: 0 0 1.25rem; }
.c-grid { display: grid; gap: 1rem; grid-template-columns: repeat(auto-fill, minmax(15rem, 1fr)); }

.course { display: flex; flex-direction: column; text-decoration: none; color: var(--ink);
  background: var(--paper); border: 1px solid var(--rule); border-radius: 10px; overflow: hidden;
  transition: border-color .15s, transform .15s; }
.course:hover, .course:focus-visible { border-color: var(--accent); transform: translateY(-2px); }
.course:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }
.c-thumb { position: relative; display: block; aspect-ratio: 16 / 9; background: var(--raised); }
.c-thumb img { width: 100%; height: 100%; object-fit: cover; display: block; }
.c-count { position: absolute; right: 0.5rem; bottom: 0.5rem; font: 500 0.72rem var(--mono); color: #fff;
  background: rgba(10, 12, 16, 0.78); padding: 0.15rem 0.45rem; border-radius: 4px; }
.c-body { display: flex; flex-direction: column; gap: 0.2rem; padding: 0.85rem 1rem 1rem; }
.c-title { font: 500 1.08rem/1.3 var(--serif); }
.c-meta { font-size: 0.9rem; color: var(--muted); }
.c-len { font: 400 0.78rem var(--mono); color: var(--muted); }
.c-card { display: flex; flex-direction: column; }
.c-hits { list-style: none; margin: 0.4rem 0 0; padding: 0; font-size: 0.9rem; }
.c-hits li { padding: 0.2rem 0; border-top: 1px dashed var(--rule); }
.c-hits a { display: grid; grid-template-columns: 1fr auto; gap: 0.5rem; }
.c-hits .lec-l { font: 400 0.75rem var(--mono); color: var(--muted); }
.c-hits-label { font: 500 0.75rem var(--mono); color: var(--pre); margin-top: 0.5rem; }
.c-top { display: flex; justify-content: space-between; align-items: flex-start; gap: 1rem; }
.yt { font: 400 0.8rem var(--mono); color: var(--muted); }
.c-empty { color: var(--muted); padding: 2rem 0; }
.c-foot { color: var(--muted); font-size: 0.92rem; margin-top: 2.5rem; }


/* Light/dark toggle */
nav { align-items: center; }
.theme-toggle { display: inline-grid; place-items: center; width: 2rem; height: 2rem; padding: 0;
  border: 1px solid var(--rule); border-radius: 6px; background: transparent; color: var(--muted); cursor: pointer; }
.theme-toggle:hover { color: var(--accent); border-color: var(--accent); }
.theme-toggle svg { width: 1rem; height: 1rem; fill: none; stroke: currentColor; stroke-width: 1.8; stroke-linecap: round; stroke-linejoin: round; }
.theme-toggle .i-sun { display: none; }
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) .theme-toggle .i-sun { display: block; }
  :root:not([data-theme="light"]) .theme-toggle .i-moon { display: none; }
}
:root[data-theme="dark"] .theme-toggle .i-sun { display: block; }
:root[data-theme="dark"] .theme-toggle .i-moon { display: none; }
:root[data-theme="light"] { color-scheme: light; }
:root[data-theme="dark"] { color-scheme: dark; }