/* ---------------------------------------------------------------
   Advanced Interface - shared styles for every page on the site.
   Week demos keep their own styles inside their own demo.html.
   --------------------------------------------------------------- */

:root {
  --bg: #f7f6f2;
  --bg-elev: #ffffff;
  --fg: #1a1a1a;
  --fg-muted: #6b6b66;
  --line: #e2e0d8;
  --accent: #2b47ff;
  --accent-soft: #e6e9ff;
  --radius: 10px;
  --max: 880px;
  --font: ui-sans-serif, system-ui, -apple-system, "Helvetica Neue", Arial, sans-serif;
  --mono: ui-monospace, SFMono-Regular, Menlo, monospace;
  color-scheme: light dark;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #121212;
    --bg-elev: #1c1c1c;
    --fg: #ededea;
    --fg-muted: #9a9a94;
    --line: #2c2c2a;
    --accent: #8fa0ff;
    --accent-soft: #23284a;
  }
}

*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--fg);
  font: 16px/1.6 var(--font);
}
a { color: inherit; text-decoration: none; }
a:hover { color: var(--accent); }
img, video, iframe { max-width: 100%; }
button { font: inherit; color: inherit; }

/* ---------- shell ---------- */
.site-header, .site-footer, .page {
  width: min(var(--max), 100% - 32px);
  margin-inline: auto;
}
.site-header {
  display: flex; align-items: baseline; justify-content: space-between; gap: 16px;
  padding: 28px 0 20px;
  border-bottom: 1px solid var(--line);
}
.site-header .brand { font-weight: 700; letter-spacing: -0.01em; }
.site-header nav { display: flex; gap: 18px; font-size: 14px; color: var(--fg-muted); }
.page { padding: 32px 0 64px; }
.site-footer {
  padding: 24px 0 40px;
  border-top: 1px solid var(--line);
  font-size: 13px; color: var(--fg-muted);
}

/* ---------- home ---------- */
.intro { margin-bottom: 28px; }
.intro h1 { font-size: 28px; margin: 0 0 6px; letter-spacing: -0.02em; }
.intro p { margin: 0; color: var(--fg-muted); }

.chips { display: flex; flex-wrap: wrap; gap: 8px; margin: 0 0 24px; padding: 0; list-style: none; }
.chip {
  border: 1px solid var(--line); background: var(--bg-elev);
  border-radius: 999px; padding: 4px 12px; font-size: 13px; cursor: pointer;
  transition: background .15s, border-color .15s;
}
.chip:hover { border-color: var(--accent); }
.chip.is-active { background: var(--accent); border-color: var(--accent); color: #fff; }
.chip .count { opacity: .6; margin-left: 4px; font-variant-numeric: tabular-nums; }

.timeline { list-style: none; margin: 0; padding: 0; display: grid; gap: 10px; }
.slot {
  display: grid; grid-template-columns: 84px 1fr; gap: 16px; align-items: start;
  padding: 16px; border: 1px solid var(--line); border-radius: var(--radius);
  background: var(--bg-elev);
}
.slot > a { display: contents; }
.slot .num { font-family: var(--mono); font-size: 13px; color: var(--fg-muted); padding-top: 3px; }
.slot .title { font-weight: 600; margin: 0; }
.slot .summary { margin: 2px 0 8px; color: var(--fg-muted); font-size: 14px; }
.slot .meta { display: flex; flex-wrap: wrap; gap: 6px; font-size: 12px; color: var(--fg-muted); }
.slot .tag { border: 1px solid var(--line); border-radius: 999px; padding: 1px 8px; }
.slot.is-upcoming { color: var(--fg-muted); background: transparent; border-style: dashed; }
.slot.is-hidden { display: none; }
@media (max-width: 520px) { .slot { grid-template-columns: 1fr; gap: 4px; } }

/* ---------- week post ---------- */
.post-head { margin-bottom: 32px; }
.post-head .kicker { font-family: var(--mono); font-size: 13px; color: var(--fg-muted); }
.post-head h1 { font-size: 34px; line-height: 1.15; letter-spacing: -0.02em; margin: 6px 0 10px; }
.post-head .meta { display: flex; flex-wrap: wrap; gap: 8px; align-items: center; font-size: 14px; color: var(--fg-muted); }
.post-head .tag { border: 1px solid var(--line); border-radius: 999px; padding: 1px 9px; font-size: 12px; }
.post-head .tag:hover { border-color: var(--accent); }
.post-head .demo-link { margin-left: auto; color: var(--accent); font-weight: 500; }

.prose { font-size: 17px; }
.prose h2 {
  font-size: 13px; text-transform: uppercase; letter-spacing: .08em; color: var(--fg-muted);
  margin: 48px 0 12px; padding-top: 16px; border-top: 1px solid var(--line);
}
.prose h2:first-child { margin-top: 0; border-top: 0; padding-top: 0; }
.prose h3 { font-size: 19px; margin: 28px 0 8px; }
.prose p, .prose ul, .prose ol { margin: 0 0 16px; }
.prose img { display: block; border-radius: var(--radius); border: 1px solid var(--line); margin: 16px 0; height: auto; }
.prose blockquote { margin: 16px 0; padding: 4px 16px; border-left: 3px solid var(--accent); color: var(--fg-muted); }
.prose code { font-family: var(--mono); font-size: .9em; background: var(--accent-soft); padding: 1px 5px; border-radius: 4px; }
.prose pre { background: var(--bg-elev); border: 1px solid var(--line); border-radius: var(--radius); padding: 14px 16px; overflow: auto; font-size: 14px; }
.prose pre code { background: none; padding: 0; }

.prose table { width: 100%; border-collapse: collapse; margin: 18px 0 24px; font-size: 15px; line-height: 1.5; }
.prose thead th {
  text-align: left; font-size: 11px; font-weight: 600;
  text-transform: uppercase; letter-spacing: .08em; color: var(--fg-muted);
  padding: 0 16px 9px 0; border-bottom: 1px solid var(--line);
}
.prose tbody td { padding: 12px 16px 12px 0; border-bottom: 1px solid var(--line); vertical-align: top; }
.prose tbody tr:last-child td { border-bottom: 0; }
.prose tbody td:first-child { font-weight: 600; }
.prose th:last-child, .prose td:last-child { padding-right: 0; }
.prose table code { font-size: .85em; }
@media (max-width: 560px) { .prose table { font-size: 13.5px; } .prose tbody td { padding-right: 10px; } }

/* Photos and scans of physical work: sketches, paper prototypes, models.
   One image:
     <figure class="shot">
       <img src="images/sketch-01.jpg" alt="what it shows" />
       <figcaption>What to notice in it.</figcaption>
     </figure>
   Several side by side: wrap the images in <div class="shot-row">. */
.prose figure.shot { margin: 20px 0 24px; }
.prose figure.shot img { margin: 0; width: 100%; }
.prose figure.shot figcaption { margin-top: 9px; font-size: 13.5px; line-height: 1.5; color: var(--fg-muted); }
.prose .shot-row { display: grid; grid-template-columns: repeat(auto-fit, minmax(190px, 1fr)); gap: 12px; }
.prose .shot-row img { height: 100%; object-fit: cover; }

.demo-frame { margin: 20px 0 24px; }
/* Each demo is a separate page, so its frame needs a height. This is only a
   default: set the real one on the iframe itself, e.g. style="height: 965px" */
.demo-frame iframe {
  width: 100%; height: 70vh; display: block; border: 1px solid var(--line);
  border-radius: var(--radius); background: var(--bg-elev);
}
.demo-frame figcaption { display: flex; justify-content: space-between; gap: 12px; font-size: 13px; color: var(--fg-muted); margin-top: 8px; }
.demo-frame figcaption a { color: var(--accent); }

.post-nav { display: flex; justify-content: space-between; gap: 16px; margin-top: 56px; padding-top: 20px; border-top: 1px solid var(--line); font-size: 14px; }
.post-nav a { color: var(--fg-muted); }
.post-nav a:hover { color: var(--accent); }
.post-nav .next { text-align: right; margin-left: auto; }