:root {
  --bg1: #FFF8E1;
  --bg2: #E1F5FE;
  --ink: #37474F;
  --ink-soft: #607D8B;
  --card: #FFFFFF;
  --line: #ECEFF1;
  --accent: #FF7043;
  --good: #43A047;
  --bad: #E53935;
  --gold: #FFC107;
  --radius: 18px;
  --shadow: 0 6px 0 rgba(0,0,0,0.06);
}
* { box-sizing: border-box; }
html, body { margin: 0; padding: 0; }
body {
  font-family: "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", sans-serif;
  color: var(--ink);
  background: linear-gradient(160deg, var(--bg1), var(--bg2));
  min-height: 100vh;
  -webkit-tap-highlight-color: transparent;
}
.wrap { max-width: 920px; margin: 0 auto; padding: 18px 16px 48px; }

/* 顶部条 */
.topbar {
  display: flex; align-items: center; justify-content: space-between;
  gap: 12px; margin-bottom: 18px; flex-wrap: wrap;
}
.brand { display: flex; align-items: center; gap: 10px; font-size: 22px; font-weight: 700; }
.brand .logo { font-size: 30px; }
.total-stars { font-size: 16px; color: var(--ink-soft); font-weight: 600; }
.total-stars b { color: var(--gold); }

/* 关卡地图 */
.levels {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(150px, 1fr));
  gap: 14px;
}
.level-card {
  background: var(--card);
  border-radius: var(--radius);
  padding: 16px 14px;
  text-align: center;
  box-shadow: var(--shadow);
  text-decoration: none;
  color: var(--ink);
  border-top: 6px solid var(--c, #999);
  transition: transform .12s ease;
  display: flex; flex-direction: column; gap: 8px; align-items: center;
}
.level-card:hover { transform: translateY(-3px); }
.level-card .em { font-size: 40px; line-height: 1; }
.level-card .ti { font-size: 16px; font-weight: 700; }
.level-card .in { font-size: 12px; color: var(--ink-soft); min-height: 30px; }
.level-card .st { font-size: 13px; color: var(--gold); font-weight: 700; }

/* 游戏页 */
.play-head { display: flex; align-items: center; justify-content: space-between; margin-bottom: 14px; gap: 10px; }
.back-btn {
  display: inline-flex; align-items: center; gap: 6px;
  background: var(--card); border: none; border-radius: 999px;
  padding: 8px 16px; font-size: 15px; color: var(--ink);
  box-shadow: var(--shadow); cursor: pointer; text-decoration: none;
}
.progress-bar { flex: 1; height: 12px; background: #fff; border-radius: 999px; overflow: hidden; box-shadow: var(--shadow); }
.progress-fill { height: 100%; background: var(--accent); width: 0; transition: width .25s ease; }
.progress-text { font-size: 14px; color: var(--ink-soft); font-weight: 600; white-space: nowrap; }

.q-card {
  background: var(--card); border-radius: var(--radius);
  padding: 26px 22px; box-shadow: var(--shadow); margin-bottom: 16px;
}
.q-num { font-size: 14px; color: var(--ink-soft); font-weight: 700; margin-bottom: 10px; }
.unit-title { font-size: 15px; color: var(--accent); font-weight: 700; margin-bottom: 6px; }
.q-text { font-size: 21px; line-height: 1.5; font-weight: 600; margin-bottom: 6px; }
.q-hint { font-size: 14px; color: var(--ink-soft); min-height: 20px; margin-top: 8px; }
.q-hint.show { color: var(--bad); }

.options { display: grid; grid-template-columns: repeat(2, 1fr); gap: 12px; }
.opt {
  background: #F5F7FA; border: 2px solid transparent; border-radius: 14px;
  padding: 16px 10px; font-size: 18px; font-weight: 600; color: var(--ink);
  cursor: pointer; transition: all .12s ease; text-align: center;
}
.opt:hover { background: #ECEFF1; }
.opt.correct { background: #E8F5E9; border-color: var(--good); color: var(--good); }
.opt.wrong { background: #FFEBEE; border-color: var(--bad); color: var(--bad); }
.opt:disabled { cursor: default; }

.feedback {
  text-align: center; font-size: 16px; font-weight: 700; min-height: 24px;
  margin: 4px 0 14px;
}
.feedback.good { color: var(--good); }
.feedback.bad { color: var(--bad); }

.next-btn {
  display: block; width: 100%; border: none; border-radius: 14px;
  padding: 15px; font-size: 18px; font-weight: 700; color: #fff;
  background: var(--accent); cursor: pointer; box-shadow: var(--shadow);
}
.next-btn:disabled { background: #CFD8DC; cursor: default; }

/* 结算页 */
.result { text-align: center; padding: 20px 0; }
.result .big { font-size: 56px; }
.result h2 { font-size: 26px; margin: 8px 0; }
.result .stars-big { font-size: 40px; letter-spacing: 6px; margin: 10px 0; }
.result .row { display: flex; gap: 12px; justify-content: center; margin-top: 18px; flex-wrap: wrap; }
.result a, .result button {
  background: var(--accent); color: #fff; border: none; border-radius: 999px;
  padding: 12px 22px; font-size: 16px; font-weight: 700; cursor: pointer; text-decoration: none;
  box-shadow: var(--shadow);
}
.result .ghost { background: var(--card); color: var(--ink); }

/* 漂浮动画 */
@keyframes pop { 0%{transform:scale(.6);opacity:0} 60%{transform:scale(1.15)} 100%{transform:scale(1);opacity:1} }
.pop { animation: pop .35s ease; }
@keyframes shake { 0%,100%{transform:translateX(0)} 25%{transform:translateX(-6px)} 75%{transform:translateX(6px)} }
.shake { animation: shake .3s ease; }

@media (max-width: 480px) {
  .q-text { font-size: 19px; }
  .opt { font-size: 16px; padding: 14px 8px; }
  .levels { grid-template-columns: repeat(2, 1fr); }
}

/* 首页引导语 */
.lead { color: var(--ink-soft); font-size: 15px; margin: 0 0 18px; line-height: 1.6; }
.lead b { color: var(--accent); }

/* 学期卡片（首页） */
.term-card { gap: 10px; padding: 20px 16px; }
.term-card .ti { font-size: 17px; }
.level-card.locked { opacity: .5; cursor: not-allowed; }
.level-card.locked:hover { transform: none; }
.locked-tip { color: var(--ink-soft); }

/* 占位 */
.placeholder { padding: 40px 16px; text-align: center; color: var(--ink-soft); font-size: 16px; background: #fff; border-radius: var(--radius); box-shadow: var(--shadow); }

/* 学期页：两张大卡片 */
.term-page { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; margin-top: 4px; }
.mode-card {
  background: var(--card); border-radius: var(--radius); padding: 28px 20px;
  text-align: center; box-shadow: var(--shadow); text-decoration: none; color: var(--ink);
  border-top: 8px solid var(--c, #999); transition: transform .12s ease;
  display: flex; flex-direction: column; gap: 12px; align-items: center;
}
.mode-card:hover { transform: translateY(-4px); }
.mode-emo { font-size: 56px; line-height: 1; }
.mode-ti { font-size: 23px; font-weight: 800; }
.mode-in { font-size: 14px; color: var(--ink-soft); line-height: 1.55; min-height: 44px; }
.mode-go { margin-top: 2px; font-size: 15px; font-weight: 700; color: var(--accent); }
.learn-mode { --c: #42A5F5; }
.play-mode { --c: #FF7043; }
@media (max-width: 480px) { .term-page { grid-template-columns: 1fr; } }

/* 首页用户区（登录态） */
.auth-box { display: flex; align-items: center; gap: 8px; flex-wrap: wrap; }
.auth-box .hi { font-size: 15px; font-weight: 600; }
.mini-btn {
  background: var(--card); border: none; border-radius: 999px; padding: 8px 14px;
  font-size: 14px; font-weight: 700; color: var(--ink); box-shadow: var(--shadow);
  text-decoration: none; cursor: pointer;
}
.mini-btn.primary { background: var(--accent); color: #fff; }
.badge { font-size: 13px; font-weight: 700; padding: 5px 12px; border-radius: 999px; text-decoration: none; }
.badge.ok { background: #E8F5E9; color: var(--good); }
.badge.need { background: #FFF3E0; color: var(--accent); }