:root {
  --bg: #0d1117;
  --panel: #161b22;
  --panel2: #1c2333;
  --gold: #f0c24b;
  --gold-dim: #b8962e;
  --text: #e6edf3;
  --dim: #8b949e;
  --red: #f85149;
  --green: #3fb950;
  --blue: #58a6ff;
  --border: #30363d;
}
* { box-sizing: border-box; margin: 0; padding: 0; }
body {
  background: var(--bg);
  color: var(--text);
  font-family: -apple-system, "PingFang SC", "Microsoft YaHei", sans-serif;
  min-height: 100vh;
  background-image:
    radial-gradient(ellipse at top, #1a2332 0%, transparent 60%),
    radial-gradient(ellipse at bottom, #101826 0%, transparent 60%);
}
#app { max-width: 860px; margin: 0 auto; padding: 12px 16px 40px; }

.topbar {
  display: flex; align-items: center; gap: 14px;
  padding: 14px 4px; border-bottom: 1px solid var(--border);
  flex-wrap: wrap;
}
.logo { font-size: 20px; font-weight: 800; color: var(--gold); letter-spacing: 1px; }
.nav { display: flex; gap: 8px; flex: 1; }
.nav-btn {
  color: var(--dim); text-decoration: none; font-size: 14px;
  padding: 6px 12px; border-radius: 8px; border: 1px solid transparent;
}
.nav-btn:hover, .nav-btn.active { color: var(--text); border-color: var(--border); background: var(--panel); }
.progress {
  height: 6px; width: 90px; border-radius: 3px; background: var(--panel2);
  overflow: hidden; border: 1px solid var(--border);
}
.progress-fill { height: 100%; background: linear-gradient(90deg, var(--gold-dim), var(--gold)); width: 0%; transition: width .4s; }

#view { padding-top: 20px; }
.card {
  background: var(--panel); border: 1px solid var(--border);
  border-radius: 12px; padding: 18px 20px; margin-bottom: 14px;
}
.card:hover { border-color: #3d4a5f; }

h1.page-title { font-size: 22px; color: var(--gold); margin-bottom: 4px; }
p.sub { color: var(--dim); font-size: 14px; margin-bottom: 18px; }

/* 大厅 */
.dungeon-list .dungeon {
  display: block; text-decoration: none; color: var(--text);
  background: var(--panel); border: 1px solid var(--border);
  border-radius: 12px; padding: 18px 20px; margin-bottom: 14px;
  position: relative; overflow: hidden;
}
.dungeon:hover { border-color: var(--gold-dim); transform: translateY(-1px); }
.dungeon .d-tag { display: inline-block; font-size: 12px; color: var(--gold); border: 1px solid var(--gold-dim); border-radius: 20px; padding: 2px 10px; margin-bottom: 8px; }
.dungeon .d-name { font-size: 19px; font-weight: 700; margin-bottom: 6px; }
.dungeon .d-intro { color: var(--dim); font-size: 14px; line-height: 1.6; }
.dungeon .d-meta { margin-top: 10px; font-size: 13px; color: var(--dim); }
.dungeon .d-status {
  position: absolute; top: 14px; right: 14px;
  font-size: 12px; padding: 4px 10px; border-radius: 20px;
}
.dungeon .d-status.cleared { background: rgba(63,185,80,.15); color: var(--green); border: 1px solid rgba(63,185,80,.4); }
.dungeon .d-status.open { background: rgba(88,166,255,.12); color: var(--blue); border: 1px solid rgba(88,166,255,.4); }

/* 副本闯关 */
.dungeon-header { margin-bottom: 16px; }
.dungeon-header .back { color: var(--dim); text-decoration: none; font-size: 14px; }
.dungeon-header .back:hover { color: var(--text); }
.dungeon-header h1 { font-size: 22px; color: var(--gold); margin: 10px 0 4px; }
.dungeon-header .d-intro { color: var(--dim); font-size: 14px; }

.stage-indicator { display: flex; gap: 8px; margin-bottom: 18px; }
.stage-dot { flex: 1; height: 8px; border-radius: 4px; background: var(--panel2); border: 1px solid var(--border); }
.stage-dot.done { background: var(--green); border-color: var(--green); }
.stage-dot.now { background: var(--gold); border-color: var(--gold); }

.level-box .monster { font-size: 15px; line-height: 1.7; color: var(--text); margin-bottom: 14px; padding: 12px 14px; background: var(--panel2); border-radius: 10px; }
.level-box .question { font-size: 17px; font-weight: 600; line-height: 1.7; margin-bottom: 16px; }
.answer-row { display: flex; gap: 10px; flex-wrap: wrap; }
.answer-row input {
  flex: 1; min-width: 200px; background: var(--bg); border: 1px solid var(--border);
  color: var(--text); border-radius: 8px; padding: 12px 14px; font-size: 16px; outline: none;
}
.answer-row input:focus { border-color: var(--gold-dim); }
.btn {
  background: linear-gradient(180deg, #2d333b, #21262d); color: var(--text);
  border: 1px solid var(--border); border-radius: 8px; padding: 12px 22px;
  font-size: 15px; font-weight: 600; cursor: pointer;
}
.btn:hover { border-color: var(--gold-dim); color: var(--gold); }
.btn.primary { background: linear-gradient(180deg, #c9a13b, #a8842a); color: #1a1405; border-color: var(--gold-dim); }
.btn.primary:hover { filter: brightness(1.1); color: #1a1405; }
.btn:disabled { opacity: .45; cursor: not-allowed; }

.feedback { margin-top: 14px; padding: 14px 16px; border-radius: 10px; font-size: 15px; line-height: 1.7; display: none; white-space: pre-line; }
.feedback.right { display: block; background: rgba(63,185,80,.12); border: 1px solid rgba(63,185,80,.45); }
.feedback.wrong { display: block; background: rgba(248,81,73,.1); border: 1px solid rgba(248,81,73,.4); }
.feedback.info { display: block; background: var(--panel2); border: 1px solid var(--border); }
.feedback .fb-title { font-weight: 700; margin-bottom: 6px; }
.feedback.right .fb-title { color: var(--green); }
.feedback.wrong .fb-title { color: var(--red); }
.feedback.info .fb-title { color: var(--blue); }

.victory { text-align: center; padding: 30px 10px; }
.victory .v-emoji { font-size: 56px; }
.victory h2 { color: var(--gold); font-size: 26px; margin: 10px 0; }
.victory .v-text { color: var(--dim); font-size: 15px; line-height: 1.8; max-width: 560px; margin: 0 auto 18px; white-space: pre-line; }
.victory .unlock { font-size: 14px; color: var(--blue); margin-top: 14px; }

/* 卡片库 */
.filter-row { display: flex; gap: 8px; flex-wrap: wrap; margin-bottom: 16px; }
.filter-chip {
  border: 1px solid var(--border); background: var(--panel); color: var(--dim);
  padding: 6px 14px; border-radius: 20px; font-size: 13px; cursor: pointer;
}
.filter-chip:hover { color: var(--text); }
.filter-chip.active { background: rgba(240,194,75,.12); border-color: var(--gold-dim); color: var(--gold); }

.card-item { cursor: pointer; }
.card-item .c-top { display: flex; justify-content: space-between; align-items: center; gap: 10px; }
.card-item .c-tag { font-size: 12px; color: var(--gold); border: 1px solid var(--gold-dim); border-radius: 20px; padding: 2px 10px; }
.card-item .c-title { font-size: 17px; font-weight: 700; margin: 8px 0 4px; }
.card-item .c-time { font-size: 12px; color: var(--dim); }
.card-item .c-badge { font-size: 12px; color: var(--green); }
.card-item .c-body { display: none; margin-top: 12px; border-top: 1px dashed var(--border); padding-top: 12px; font-size: 14px; line-height: 1.8; white-space: pre-line; }
.card-item.open .c-body { display: block; }
.card-item .c-answer { margin-top: 10px; font-size: 14px; line-height: 1.8; white-space: pre-line; background: var(--panel2); border-radius: 8px; padding: 12px; }
.card-item .c-rpg { margin-top: 10px; font-size: 13px; color: var(--blue); }
.card-item .c-rpg a { color: var(--blue); }

.foot { text-align: center; color: var(--dim); font-size: 13px; margin-top: 30px; }
.foot a { color: var(--blue); text-decoration: none; }
.foot a:hover { text-decoration: underline; }
.foot .updated { margin-top: 6px; font-size: 12px; color: var(--dim); }
.card-item.target { border-color: var(--gold-dim); box-shadow: 0 0 0 1px var(--gold-dim); }
.victory .unlock a { color: var(--blue); text-decoration: none; }
.victory .unlock a:hover { text-decoration: underline; }
.empty { text-align: center; color: var(--dim); padding: 40px 0; font-size: 15px; }

@media (max-width: 560px) {
  .logo { font-size: 17px; }
  .answer-row input { min-width: 100%; }
}

/* ---------- 真题选择题选项 ---------- */
.opt-list { display: grid; gap: 8px; margin: 12px 0 14px; }
.opt-btn {
  display: flex; gap: 10px; align-items: flex-start; text-align: left;
  background: var(--panel2); border: 1px solid var(--border); color: var(--text);
  border-radius: 10px; padding: 11px 13px; font-size: 15px; line-height: 1.7;
  cursor: pointer; transition: border-color .15s, background .15s;
}
.opt-btn:hover:not(:disabled) { border-color: var(--gold-dim); background: #202838; }
.opt-btn:disabled { opacity: .55; cursor: default; }
.opt-btn .ok {
  flex: none; width: 22px; height: 22px; border-radius: 50%;
  display: inline-flex; align-items: center; justify-content: center;
  font-weight: 700; font-size: 13px; color: var(--gold);
  border: 1px solid var(--gold-dim); background: rgba(240,194,75,.08);
}
.opt-btn .ot { flex: 1; }
.feedback .katex, .question .katex, .opt-btn .katex { font-size: 1.02em; }