/* 答题器样式 */

:root {
  --bg: #0e1116;
  --panel: #161a22;
  --panel-2: #1e2430;
  --line: #2a3140;
  --text: #e9edf4;
  --muted: #8b93a3;
  --accent: #4a90d9;
  --ok: #3ecf8e;
  --bad: #e94b3c;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 24px 16px;
  background: radial-gradient(900px 500px at 50% -10%, #1a2233 0%, var(--bg) 65%);
  color: var(--text);
  font-family: "Segoe UI", "PingFang SC", "Microsoft YaHei", system-ui, sans-serif;
  -webkit-font-smoothing: antialiased;
}

#app { width: min(660px, 100%); }

.screen {
  padding: 28px;
  border: 1px solid var(--line);
  border-radius: 20px;
  background: var(--panel);
  box-shadow: 0 24px 60px rgba(0, 0, 0, .5);
}

h1 { margin: 0 0 10px; font-size: 22px; font-weight: 600; letter-spacing: .5px; }

.sub { margin: 0 0 22px; color: var(--muted); font-size: 14px; line-height: 1.7; }
.hint { margin: 0; color: var(--muted); font-size: 13px; line-height: 2; }

.hint code, .sub code {
  padding: 2px 6px;
  border-radius: 6px;
  background: var(--panel-2);
  color: #9ecbff;
  font-size: 12px;
  word-break: break-all;
}

/* 学科选择 */
.subjects { display: grid; gap: 10px; margin: 0; padding: 0; list-style: none; }

.subject {
  width: 100%;
  display: grid;
  gap: 4px;
  padding: 16px 18px;
  text-align: left;
  cursor: pointer;
  font: inherit;
  color: var(--text);
  background: var(--panel-2);
  border: 1px solid var(--line);
  border-left: 4px solid var(--c, var(--accent));
  border-radius: 12px;
  transition: background .15s, border-color .15s;
}
.subject:hover { background: #232b39; border-color: var(--c, var(--accent)); }
.subject:active { transform: scale(.995); }
.subject-name { font-size: 16px; font-weight: 600; }
.subject-info { font-size: 12px; color: var(--muted); }

/* 顶栏 */
.bar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  margin-bottom: 12px;
  font-size: 13px;
  color: var(--muted);
}
.bar-left { display: flex; align-items: center; gap: 8px; }
.bar-right { display: flex; align-items: center; gap: 14px; }
.score b { color: var(--text); font-size: 15px; }

.time {
  font-weight: 600;
  font-variant-numeric: tabular-nums;
  color: var(--text);
  transition: color .2s;
}
.time.danger { color: var(--bad); }

.badge {
  padding: 2px 9px;
  border-radius: 99px;
  font-size: 12px;
  line-height: 1.5;
  color: var(--c, var(--muted));
  border: 1px solid currentColor;
  background: rgba(255, 255, 255, .03);
}

/* 计时条 */
.timer {
  height: 6px;
  margin-bottom: 18px;
  border-radius: 99px;
  overflow: hidden;
  background: var(--panel-2);
}
.timer-fill {
  height: 100%;
  width: 100%;
  border-radius: 99px;
  background: var(--accent);
  transition: width .12s linear, background .2s;
}
.timer-fill.danger { background: var(--bad); }

/* 题目 */
.meta { display: flex; align-items: center; gap: 10px; margin-bottom: 10px; }
.points { font-size: 12px; color: var(--muted); }

.question {
  margin: 0 0 18px;
  font-size: 17px;
  line-height: 1.7;
  word-break: break-word;
}

/* 选项 */
.options { display: grid; gap: 10px; margin: 0 0 16px; padding: 0; list-style: none; }

.option {
  width: 100%;
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 13px 16px;
  text-align: left;
  cursor: pointer;
  font: inherit;
  font-size: 15px;
  color: var(--text);
  background: var(--panel-2);
  border: 1px solid var(--line);
  border-radius: 12px;
  transition: border-color .15s, background .15s, transform .1s;
}
.option:hover:not(:disabled) { border-color: var(--accent); background: #232b39; }
.option:active:not(:disabled) { transform: scale(.995); }
.option:disabled { cursor: default; }

.option .key {
  flex: none;
  width: 26px;
  height: 26px;
  display: grid;
  place-items: center;
  border-radius: 8px;
  font-size: 12px;
  font-weight: 600;
  color: var(--muted);
  background: rgba(255, 255, 255, .06);
}
.option .text { flex: 1; line-height: 1.5; word-break: break-word; }

.option.correct { border-color: var(--ok); background: rgba(62, 207, 142, .12); }
.option.correct .key { background: var(--ok); color: #06231a; }
.option.wrong { border-color: var(--bad); background: rgba(233, 75, 60, .12); }
.option.wrong .key { background: var(--bad); color: #2a0806; }

/* 反馈 */
.feedback { min-height: 22px; margin: 0 0 16px; font-size: 14px; color: var(--muted); }
.feedback.ok { color: var(--ok); }
.feedback.bad { color: var(--bad); }

/* 按钮 */
.btn {
  width: 100%;
  padding: 13px 18px;
  cursor: pointer;
  font: inherit;
  font-size: 15px;
  color: var(--text);
  background: var(--panel-2);
  border: 1px solid var(--line);
  border-radius: 12px;
  transition: border-color .15s, background .15s;
}
.btn:hover { border-color: var(--accent); }
.btn.primary {
  font-weight: 600;
  color: #06192e;
  background: var(--accent);
  border-color: var(--accent);
}
.btn.primary:hover { background: #5b9de4; }
.hidden { display: none !important; }

.actions { display: grid; gap: 10px; }

/* 结算 */
.result { margin: 4px 0 18px; }
.result-score { font-size: 52px; font-weight: 700; line-height: 1.1; color: var(--accent); }
.result-sub { margin-top: 6px; font-size: 13px; color: var(--muted); }

@media (max-width: 480px) {
  .screen { padding: 20px; border-radius: 16px; }
  .question { font-size: 16px; }
}