:root {
  --bg: #fafaf8;
  --surface: #ffffff;
  --text: #1d1d1f;
  --muted: #6e6e73;
  --border: #e3e3e0;
  --accent: #2f5bd3;
  --new: #2f5bd3;
  --learn: #c2410c;
  --review: #15803d;
  --again: #b91c1c;
  --hard: #a16207;
  --good: #15803d;
  --easy: #2f5bd3;
  --radius: 10px;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #161618;
    --surface: #1f1f22;
    --text: #ececec;
    --muted: #9a9aa0;
    --border: #333338;
    --accent: #7c9cf5;
    --new: #7c9cf5;
    --learn: #fb923c;
    --review: #4ade80;
    --again: #f87171;
    --hard: #facc15;
    --good: #4ade80;
    --easy: #7c9cf5;
  }
}

* { box-sizing: border-box; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font: 16px/1.5 system-ui, -apple-system, "Segoe UI", Roboto, "Noto Sans Hebrew", Arial, sans-serif;
}
a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }

header {
  display: flex; align-items: center; justify-content: space-between;
  max-width: 760px; margin: 0 auto; padding: 16px;
}
.logo { font-weight: 700; font-size: 20px; color: var(--text); }
.logo span { color: var(--muted); font-weight: 400; font-size: 15px; margin-left: 4px; }
nav { display: flex; gap: 16px; align-items: center; font-size: 15px; }
nav a { color: var(--muted); }

main { max-width: 760px; margin: 0 auto; padding: 0 16px 48px; }
h1 { font-size: 22px; margin: 8px 0 20px; }
h2 { font-size: 17px; margin: 32px 0 12px; }

.box {
  background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius);
  padding: 20px;
}
.narrow { max-width: 360px; margin: 40px auto; }

label { display: block; font-size: 14px; color: var(--muted); margin: 12px 0 4px; }
input[type=text], input[type=password], input[type=number] {
  width: 100%; padding: 9px 11px; font: inherit; color: var(--text);
  background: var(--bg); border: 1px solid var(--border); border-radius: 8px;
}
button {
  font: inherit; padding: 9px 16px; border-radius: 8px; cursor: pointer;
  border: 1px solid var(--border); background: var(--surface); color: var(--text);
}
button:hover { border-color: var(--muted); }
button.primary { background: var(--accent); color: #fff; border-color: var(--accent); }
button.link { border: none; background: none; padding: 0; color: var(--accent); }
button:disabled { opacity: .5; cursor: default; }
.danger { color: var(--again); }
.error { color: var(--again); font-size: 14px; min-height: 1.5em; margin: 8px 0 0; }
.muted { color: var(--muted); font-size: 14px; }
.row { display: flex; gap: 8px; align-items: center; flex-wrap: wrap; }
.spacer { flex: 1; }

/* dashboard */
.decks { list-style: none; padding: 0; margin: 0; }
.decks li {
  display: flex; align-items: center; gap: 12px;
  padding: 14px 16px; border-bottom: 1px solid var(--border);
}
.decks li:last-child { border-bottom: none; }
.decks a.name { flex: 1; color: var(--text); font-weight: 500; }
.counts { display: flex; gap: 14px; font-variant-numeric: tabular-nums; font-size: 15px; min-width: 120px; justify-content: flex-end; }
.counts .n { color: var(--new); } .counts .l { color: var(--learn); } .counts .r { color: var(--review); }
.counts .zero { color: var(--border); }
.progress { height: 4px; background: var(--border); border-radius: 2px; margin-top: 6px; overflow: hidden; }
.progress div { height: 100%; background: var(--review); }
.deck-main { flex: 1; min-width: 0; }

/* study */
.study-top { display: flex; align-items: center; gap: 12px; margin-bottom: 16px; }
.study-top .title { flex: 1; font-weight: 500; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.card-frame {
  display: block; width: 100%;
  height: calc(100vh - 190px); height: calc(100dvh - 190px); min-height: 400px;
  border: 1px solid var(--border); border-radius: var(--radius); background: #fff;
}
.answer-bar { display: flex; gap: 8px; margin-top: 16px; justify-content: center; }
.answer-bar button { flex: 1; max-width: 160px; display: flex; flex-direction: column; align-items: center; padding: 10px; }
.answer-bar button small { color: var(--muted); font-size: 12px; }
.answer-bar .again { color: var(--again); } .answer-bar .hard { color: var(--hard); }
.answer-bar .good { color: var(--good); } .answer-bar .easy { color: var(--easy); }
.answer-bar .show { max-width: 340px; }
.hint { text-align: center; margin-top: 16px; }
.done { text-align: center; padding: 60px 20px; }
.done .big { font-size: 40px; }

table { width: 100%; border-collapse: collapse; font-size: 14px; }
td, th { text-align: left; padding: 8px 6px; border-bottom: 1px solid var(--border); }
th { color: var(--muted); font-weight: 500; }

@media (max-width: 520px) {
  .answer-bar { gap: 6px; }
  .answer-bar button { padding: 8px 4px; }
  .counts { min-width: 0; gap: 10px; }
}