:root {
  --bg: #f6f4ef; --fg: #1d232b; --muted: #5d6673; --card: #ffffff; --line: #e2ded5;
  --accent: #1f3a5f; --accent-fg: #ffffff; --danger: #a12a2a; --radius: 12px;
  color-scheme: light;
}
@media (prefers-color-scheme: dark) {
  :root { --bg: #14181d; --fg: #e8e6e1; --muted: #9aa3ae; --card: #1d232b; --line: #2c343e;
          --accent: #8fb3e0; --accent-fg: #0f1720; --danger: #ef8a8a; color-scheme: dark; }
}
* { box-sizing: border-box; }
body { margin: 0; background: var(--bg); color: var(--fg);
       font: 17px/1.5 system-ui, -apple-system, "Segoe UI", Roboto, sans-serif; }
main { max-width: 680px; margin: 0 auto; padding: 16px 16px 48px; }
.narrow { max-width: 460px; }
h1 { font-size: 1.6rem; margin: 8px 0 16px; }
h2 { font-size: 1.1rem; margin: 0 0 6px; }
a { color: var(--accent); }
small { color: var(--muted); }
.top { display: flex; align-items: center; justify-content: space-between; gap: 12px;
       padding: 12px 16px; border-bottom: 1px solid var(--line); background: var(--card); }
.top nav { display: flex; align-items: center; gap: 12px; }
.brand { font-weight: 700; text-decoration: none; color: var(--fg); }
.btn { display: inline-block; padding: 12px 18px; border-radius: var(--radius); border: 1px solid var(--line);
       background: var(--card); color: var(--fg); font: inherit; text-decoration: none; cursor: pointer; }
.btn.small { padding: 8px 12px; font-size: 0.95rem; }
.btn.primary { background: var(--accent); color: var(--accent-fg); border-color: var(--accent); }
.btn.danger { color: var(--danger); }
button.link { background: none; border: 0; color: var(--accent); font: inherit; cursor: pointer; padding: 0; }
form.inline { display: inline; }
.stack { display: flex; flex-direction: column; gap: 14px; }
.stack label { display: flex; flex-direction: column; gap: 6px; }
.row { display: flex; gap: 10px; align-items: center; flex-wrap: wrap; }
input[type=text], input[type=password], input:not([type]), select {
  font: inherit; padding: 10px 12px; border-radius: 10px; border: 1px solid var(--line);
  background: var(--card); color: var(--fg); min-width: 0; }
.stack label.check { flex-direction: row; align-items: flex-start; gap: 10px; }
.check input { width: 22px; height: 22px; margin-top: 2px; flex: none; }
.error { color: var(--danger); }
.empty { color: var(--muted); }
.cards { display: flex; flex-direction: column; gap: 12px; }
.card { background: var(--card); border: 1px solid var(--line); border-radius: var(--radius); padding: 14px 16px; }
.card .meta { color: var(--muted); display: flex; flex-direction: column; gap: 8px; }
.card .row { margin-top: 10px; }
progress { width: 100%; height: 8px; accent-color: var(--accent); }
.chapters { list-style: none; padding: 0; margin: 0; display: flex; flex-direction: column; gap: 10px; }
.chapters li { background: var(--card); border: 1px solid var(--line); border-radius: var(--radius); padding: 12px; }
.chapters .preview { color: var(--muted); font-size: 0.92rem; }
.player { background: var(--card); border: 1px solid var(--line); border-radius: var(--radius); padding: 16px;
          position: sticky; top: 0; z-index: 1; }
.player .now { font-weight: 600; margin: 0 0 8px; }
.player input[type=range] { width: 100%; accent-color: var(--accent); }
.player .times { display: flex; justify-content: space-between; color: var(--muted); margin: 4px 0 8px; font-variant-numeric: tabular-nums; }
.controls { display: flex; justify-content: center; align-items: center; gap: 10px; margin: 6px 0 12px; }
.controls button { min-width: 52px; min-height: 52px; border-radius: 50%; border: 1px solid var(--line);
                   background: var(--bg); color: var(--fg); font: 600 1rem system-ui; cursor: pointer; }
.controls .play { min-width: 68px; min-height: 68px; background: var(--accent); color: var(--accent-fg); font-size: 1.4rem; }
.chapter-list { padding-left: 0; list-style: none; }
.chapter-list button { width: 100%; text-align: left; padding: 12px; background: none; border: 0;
                       border-bottom: 1px solid var(--line); color: var(--fg); font: inherit; cursor: pointer;
                       display: flex; justify-content: space-between; gap: 12px; }
.chapter-list button.active { color: var(--accent); font-weight: 600; }
.downloads { display: flex; flex-direction: column; gap: 10px; margin: 20px 0; }
table { width: 100%; border-collapse: collapse; }
td, th { text-align: left; padding: 8px 4px; border-bottom: 1px solid var(--line); vertical-align: top; }