/* Shared styles for studyguide.smidge.page */
:root {
  --bg: #f6f7fb; --card: #ffffff; --ink: #1d2340; --muted: #5d6685; --line: #e3e6f0;
  --accent: #3e7bfa; --accent-soft: #e8f0ff;
  --sci: #12a37f; --sci-soft: #e2f6ef;
  --math: #7a5af8; --math-soft: #efeaff;
  --ela: #e8590c; --ela-soft: #fff0e6;
  --soc: #d6336c; --soc-soft: #ffe8ef;
  --good: #12a37f; --bad: #e03131; --warn: #f08c00;
  --radius: 16px;
  color-scheme: light dark;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #11141f; --card: #1a1f2e; --ink: #e8ebf5; --muted: #9aa3c0; --line: #2b3247;
    --accent: #6b9bff; --accent-soft: #1d2a47;
    --sci-soft: #123128; --math-soft: #241d45; --ela-soft: #3a2414; --soc-soft: #3a1726;
  }
}
* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; }
body {
  margin: 0; background: var(--bg); color: var(--ink);
  font: 17px/1.55 system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
}
a { color: var(--accent); }
.wrap { max-width: 860px; margin: 0 auto; padding: 0 16px; }
header.top { padding: 18px 0 6px; }
header.top .crumbs { font-size: 14px; color: var(--muted); }
header.top .crumbs a { color: var(--muted); text-decoration: none; }
h1 { font-size: clamp(26px, 6vw, 38px); line-height: 1.15; margin: 6px 0 8px; }
h2 { font-size: 23px; margin: 0 0 10px; line-height: 1.25; }
h3 { font-size: 18px; margin: 18px 0 6px; }
p { margin: 8px 0; }
.lead { font-size: 18px; color: var(--muted); }
.card {
  background: var(--card); border: 1px solid var(--line); border-radius: var(--radius);
  padding: 18px; margin: 16px 0; box-shadow: 0 1px 2px rgba(0,0,0,.04);
}
section.card { scroll-margin-top: 64px; }
.tag { display: inline-block; font-size: 12px; font-weight: 700; letter-spacing: .04em; text-transform: uppercase;
  padding: 3px 9px; border-radius: 999px; background: var(--sci-soft); color: var(--sci); }
.btn {
  appearance: none; border: 1px solid var(--line); background: var(--card); color: var(--ink);
  font: 600 15px/1 inherit; font-family: inherit; padding: 11px 14px; min-height: 44px; border-radius: 12px; cursor: pointer;
}
.btn.primary { background: var(--accent); border-color: var(--accent); color: #fff; }
.btn.on { background: var(--accent-soft); border-color: var(--accent); color: var(--accent); }
.btn:disabled { opacity: .5; cursor: default; }
.row { display: flex; flex-wrap: wrap; gap: 8px; align-items: center; margin: 10px 0; }
canvas { width: 100%; display: block; border-radius: 12px; background: var(--bg); touch-action: pan-y; }
label.slider { display: flex; gap: 10px; align-items: center; font-size: 15px; margin: 6px 0; }
label.slider span { min-width: 92px; color: var(--muted); }
label.slider input { flex: 1; min-height: 32px; }
.key { background: var(--accent-soft); border-left: 4px solid var(--accent); padding: 10px 14px; border-radius: 8px; margin: 12px 0; }
.key b:first-child { color: var(--accent); }
.vocab { display: grid; grid-template-columns: 1fr; gap: 8px; }
@media (min-width: 620px) { .vocab { grid-template-columns: 1fr 1fr; } }
.vocab div { border: 1px solid var(--line); border-radius: 12px; padding: 10px 12px; font-size: 15px; }
.vocab b { display: block; font-size: 16px; }
table { border-collapse: collapse; width: 100%; font-size: 15px; }
th, td { border-bottom: 1px solid var(--line); padding: 8px 6px; text-align: left; }
details.qa { border: 1px solid var(--line); border-radius: 12px; padding: 0 14px; margin: 10px 0; }
details.qa summary { cursor: pointer; padding: 12px 0; font-weight: 600; list-style: none; }
details.qa summary::-webkit-details-marker { display: none; }
details.qa summary::before { content: "▸ "; color: var(--accent); }
details.qa[open] summary::before { content: "▾ "; }
details.qa .ans { padding: 0 0 12px; }
nav.toc {
  position: sticky; top: 0; z-index: 5; background: var(--bg); padding: 8px 0;
  display: flex; gap: 6px; overflow-x: auto; scrollbar-width: none;
}
nav.toc::-webkit-scrollbar { display: none; }
nav.toc a {
  flex: none; font-size: 14px; font-weight: 600; text-decoration: none; color: var(--ink);
  background: var(--card); border: 1px solid var(--line); border-radius: 999px; padding: 8px 12px;
}
.legend { display: flex; flex-wrap: wrap; gap: 12px; font-size: 13px; color: var(--muted); margin-top: 6px; }
.legend i { display: inline-block; width: 12px; height: 12px; border-radius: 3px; margin-right: 5px; vertical-align: -1px; }
.muted { color: var(--muted); }
.small { font-size: 14px; }
/* Quiz */
.quiz .q { font-weight: 700; margin: 6px 0 10px; font-size: 18px; }
.quiz .opts { display: grid; gap: 8px; }
.quiz .opt { text-align: left; font-weight: 500; line-height: 1.35; }
.quiz .opt.right { border-color: var(--good); background: var(--sci-soft); }
.quiz .opt.wrong { border-color: var(--bad); background: rgba(224,49,49,.08); }
.quiz .why { margin-top: 10px; font-size: 15px; }
.progress { height: 6px; background: var(--line); border-radius: 99px; overflow: hidden; margin-bottom: 12px; }
.progress div { height: 100%; background: var(--accent); width: 0; transition: width .3s; }