:root{
  --bg:#0f172a;
  --panel:#111827;
  --panel-2:#1f2937;
  --border:#1e293b;
  --text:#e5e7eb;
  --muted:#94a3b8;
  --primary:#3b82f6;
  --primary-2:#60a5fa;
  --good:#10b981;
  --bad:#ef4444;
  --warn:#f59e0b;
  --chip:#1e293b;
  --chip-active:#3b82f6;
  --shadow:0 8px 30px rgba(0,0,0,.25);
}

*{box-sizing:border-box}
html,body{margin:0;padding:0;background:var(--bg);color:var(--text);font:15px/1.55 -apple-system,"Segoe UI","PingFang SC","Microsoft YaHei",Arial,sans-serif;}

.topbar{
  display:flex;align-items:center;justify-content:space-between;
  padding:14px 24px;border-bottom:1px solid var(--border);
  background:linear-gradient(180deg,#0b1220,#0f172a);
  position:sticky;top:0;z-index:10;
}
.brand{font-weight:600;letter-spacing:.5px}
.meta{color:var(--muted);font-size:13px;display:flex;gap:14px;align-items:center}

/* 导入页 */
.dropzone{
  display:flex;flex-direction:column;align-items:center;justify-content:center;gap:8px;
  padding:48px 16px;background:var(--panel-2);border:2px dashed var(--border);
  border-radius:14px;cursor:pointer;transition:all .15s;text-align:center;
}
.dropzone:hover{border-color:var(--primary-2);background:rgba(59,130,246,.06)}
.dropzone.drag{border-color:var(--primary);background:rgba(59,130,246,.12)}
.dz-icon{font-size:36px}
.dz-title{font-size:16px;font-weight:500}
.dz-hint{font-size:12px;color:var(--muted)}
.error{
  margin-top:14px;padding:10px 12px;border-radius:8px;
  background:rgba(239,68,68,.12);border:1px solid rgba(239,68,68,.4);
  color:#fca5a5;font-size:13px;white-space:pre-wrap;
}
details summary{cursor:pointer;color:var(--muted);font-size:13px}
code{background:var(--bg);border:1px solid var(--border);padding:1px 6px;border-radius:4px;font-size:12px}

main{max-width:980px;margin:24px auto;padding:0 16px}
.card{
  background:var(--panel);border:1px solid var(--border);
  border-radius:14px;padding:24px;box-shadow:var(--shadow);
}
h1{margin:0 0 8px;font-size:22px}
h2{margin:0 0 12px;font-size:18px}
h3{margin:0 0 10px;font-size:14px;color:var(--muted);font-weight:600;letter-spacing:.4px;text-transform:uppercase}
.muted{color:var(--muted)}
.hint{color:var(--muted);font-size:12px;margin:6px 0 0}

.grid{display:grid;grid-template-columns:1fr 1fr;gap:16px;margin:18px 0}
.block{background:var(--panel-2);border:1px solid var(--border);border-radius:10px;padding:14px}
.block.full{grid-column:1 / -1}

.chips{display:flex;flex-wrap:wrap;gap:8px}
.chip{
  background:var(--chip);color:var(--text);
  border:1px solid var(--border);
  padding:6px 12px;border-radius:999px;font-size:13px;cursor:pointer;
  user-select:none;transition:all .15s;
}
.chip:hover{border-color:var(--primary-2)}
.chip.active{background:var(--chip-active);border-color:var(--chip-active);color:#fff}
.chips.kp{max-height:180px;overflow:auto;padding-right:4px}
.kp-toolbar{display:flex;gap:10px;margin-bottom:8px}
.link{background:none;border:0;color:var(--primary-2);cursor:pointer;font-size:13px;padding:0}
.link:hover{text-decoration:underline}
.link.danger{color:var(--bad)}

input[type=number]{
  width:100%;padding:8px 10px;border:1px solid var(--border);
  background:var(--bg);color:var(--text);border-radius:8px;font-size:14px;
}
.radio{display:flex;align-items:center;gap:8px;padding:6px 0;cursor:pointer}
.radio input{accent-color:var(--primary)}

.actions{display:flex;gap:10px;flex-wrap:wrap;margin-top:18px}
button.primary,button.ghost{
  padding:10px 18px;border-radius:8px;font-size:14px;cursor:pointer;border:1px solid transparent;font-weight:500;
}
button.primary{background:var(--primary);color:#fff}
button.primary:hover{background:var(--primary-2)}
button.primary:disabled{opacity:.5;cursor:not-allowed}
button.ghost{background:transparent;color:var(--text);border-color:var(--border)}
button.ghost:hover{border-color:var(--primary-2)}

/* quiz */
.qheader{display:flex;align-items:center;justify-content:space-between;gap:12px;margin-bottom:8px}
.progress{font-size:13px;color:var(--muted)}
.qtags{display:flex;gap:6px;flex-wrap:wrap}
.tag{background:var(--chip);border:1px solid var(--border);color:var(--muted);padding:2px 8px;border-radius:6px;font-size:12px}
.tag-type{color:#a5b4fc}
.tag-kp{color:#86efac}
.tag-diff{color:#fbbf24}
.tag-mastery{font-weight:600;border-width:1.5px}

/* 掌握度 chip 颜色 */
.chip[data-value="fresh"].active{background:#ef4444;border-color:#ef4444}
.chip[data-value="medium"].active{background:#f59e0b;border-color:#f59e0b}
.chip[data-value="mastered"].active{background:#10b981;border-color:#10b981}

/* 掌握度概览 */
.mastery-overview{margin:14px 0 18px}
.mastery-overview h3{margin-bottom:8px}
.mbar{display:flex;height:14px;background:var(--border);border-radius:7px;overflow:hidden}
.mseg-mastered{background:#10b981}
.mseg-medium{background:#f59e0b}
.mseg-fresh{background:#ef4444}
.mseg-untouched{background:#374151}
.mlegend{display:flex;flex-wrap:wrap;gap:14px;margin-top:8px;font-size:12px;color:var(--muted)}
.mlegend .dot{display:inline-block;width:8px;height:8px;border-radius:50%;margin-right:4px;vertical-align:middle}
.dot-mastered{background:#10b981}
.dot-medium{background:#f59e0b}
.dot-fresh{background:#ef4444}
.dot-untouched{background:#374151}

/* 搜索框 */
input[type=text]{
  width:100%;padding:9px 10px;border:1px solid var(--border);
  background:var(--bg);color:var(--text);border-radius:8px;font-size:14px;
}
input[type=text]:focus{outline:none;border-color:var(--primary)}

.bar{height:4px;background:var(--border);border-radius:2px;overflow:hidden;margin-bottom:18px}
.bar-fill{height:100%;background:var(--primary);transition:width .25s}

.stem{margin:6px 0 18px;line-height:1.6;font-weight:500;font-size:17px}
.options{display:flex;flex-direction:column;gap:10px}
.option{
  background:var(--panel-2);border:1px solid var(--border);
  border-radius:10px;padding:12px 14px;cursor:pointer;
  display:flex;align-items:flex-start;gap:12px;transition:all .15s;
  user-select:none;
}
.option:hover{border-color:var(--primary-2)}
.option.selected{border-color:var(--primary);background:rgba(59,130,246,.12)}
.option.correct{border-color:var(--good);background:rgba(16,185,129,.12)}
.option.wrong  {border-color:var(--bad); background:rgba(239,68,68,.12)}
.option.disabled{cursor:default;opacity:.85}
.option .label{
  flex:0 0 28px;height:28px;line-height:28px;text-align:center;
  background:var(--bg);border:1px solid var(--border);border-radius:6px;font-weight:600;
}
.option.selected .label{background:var(--primary);border-color:var(--primary);color:#fff}
.option.correct  .label{background:var(--good);border-color:var(--good);color:#fff}
.option.wrong    .label{background:var(--bad); border-color:var(--bad); color:#fff}
.option .text{flex:1}

.feedback{margin:18px 0 0;padding:14px;background:var(--panel-2);border:1px solid var(--border);border-radius:10px}
.feedback .result{font-weight:600;margin-bottom:6px}
.feedback .result.correct{color:var(--good)}
.feedback .result.wrong  {color:var(--bad)}
.feedback .answer{color:var(--muted);margin-bottom:6px}
.feedback .idea{color:var(--muted);font-size:13px;white-space:pre-wrap}

/* 自动跳转提示 */
.autonext-hint{
  display:none;align-items:center;justify-content:space-between;gap:10px;
  margin-top:10px;padding:8px 12px;border-radius:8px;
  background:rgba(16,185,129,.1);border:1px solid rgba(16,185,129,.3);
  color:#86efac;font-size:13px;
}
.autonext-hint.show{display:flex;animation:autonextPulse 0.8s linear}
.autonext-hint .link{color:#86efac}
@keyframes autonextPulse{
  0%{background:rgba(16,185,129,.25)}
  100%{background:rgba(16,185,129,.05)}
}

/* AI 解析区 */
.ai-section{margin-top:10px;padding-top:10px;border-top:1px dashed var(--border)}
.ai-trigger{font-size:13px}
.ai-content{
  margin-top:8px;font-size:13px;line-height:1.7;color:var(--text);
  white-space:pre-wrap;word-break:break-word;
  background:rgba(99,102,241,.08);border:1px solid rgba(99,102,241,.25);
  padding:10px 12px;border-radius:8px;
}
.ai-content.loading{color:var(--muted);font-style:italic}
.ai-content.error{background:rgba(239,68,68,.08);border-color:rgba(239,68,68,.3);color:#fca5a5}
.ai-content .reasoning{margin-bottom:8px;border-bottom:1px dashed var(--border);padding-bottom:8px}
.ai-content .reasoning summary{cursor:pointer;color:var(--muted);font-size:12px;font-weight:500}
.ai-content .reasoning pre{
  margin:6px 0 0;padding:8px;background:rgba(0,0,0,.2);border-radius:6px;
  font-size:12px;color:var(--muted);white-space:pre-wrap;word-break:break-word;
  max-height:200px;overflow:auto;font-family:inherit;line-height:1.6;
}
.ai-content .ai-final{font-size:13px;line-height:1.7}

/* 聊天式 AI 解析 */
.chat-msg{margin-bottom:10px}
.chat-msg .chat-role{font-size:11px;color:var(--muted);margin-bottom:3px;font-weight:500}
.chat-msg .chat-text{
  font-size:13px;line-height:1.7;white-space:pre-wrap;word-break:break-word;
  padding:8px 10px;border-radius:8px;
}
.chat-user .chat-text{background:rgba(59,130,246,.12);border:1px solid rgba(59,130,246,.25)}
.chat-assistant .chat-text{background:rgba(99,102,241,.08);border:1px solid rgba(99,102,241,.2)}
.chat-msg.error .chat-text{background:rgba(239,68,68,.08);border-color:rgba(239,68,68,.3);color:#fca5a5}

.chat-ask{
  margin-top:10px;padding-top:10px;border-top:1px dashed var(--border);
  display:flex;flex-direction:column;gap:8px;
}
.chat-ask textarea{
  width:100%;padding:8px 10px;border:1px solid var(--border);background:var(--bg);
  color:var(--text);border-radius:8px;font-size:13px;line-height:1.5;resize:none;
  font-family:inherit;min-height:38px;max-height:120px;
}
.chat-ask textarea:focus{outline:none;border-color:var(--primary)}
.chat-actions{display:flex;justify-content:space-between;align-items:center;gap:10px}
.chat-actions .primary{padding:6px 16px;font-size:13px;min-height:34px}

.field select{
  padding:9px 10px;border:1px solid var(--border);background:var(--bg);
  color:var(--text);border-radius:8px;font-size:14px;
}

/* 设置弹窗 */
.modal{
  position:fixed;inset:0;background:rgba(0,0,0,.55);z-index:100;
  display:flex;align-items:center;justify-content:center;padding:16px;
}
.modal[hidden]{display:none}   /* 修正：class 选择器与 [hidden] 优先级相同，必须显式声明 */

/* Toast 提示 */
.toast{
  position:fixed;left:50%;top:max(20px,env(safe-area-inset-top));
  transform:translate(-50%,-12px);
  background:rgba(15,23,42,.96);border:1px solid var(--border);
  color:var(--text);padding:10px 16px;border-radius:8px;font-size:13px;
  box-shadow:var(--shadow);z-index:200;
  opacity:0;pointer-events:none;transition:opacity .2s,transform .2s;
}
.toast.show{opacity:1;transform:translate(-50%,0)}

/* 续做提示 banner */
.resume-banner{
  display:flex;justify-content:space-between;align-items:center;gap:12px;flex-wrap:wrap;
  margin:14px 0 6px;padding:12px 14px;
  background:rgba(59,130,246,.1);border:1px solid rgba(59,130,246,.35);border-radius:10px;
}
.resume-banner button{padding:6px 14px;font-size:13px;min-height:34px;border-radius:6px}

/* 历史记录入口 */
.history-link{margin-top:14px;padding-top:14px;border-top:1px dashed var(--border);text-align:center}

/* 历史记录页 */
.history-item{
  background:var(--panel-2);border:1px solid var(--border);border-radius:10px;
  padding:12px 14px;margin-bottom:10px;
}
.history-item .row1{display:flex;justify-content:space-between;align-items:center;margin-bottom:4px}
.history-item .qstem{font-weight:500}
.history-item .meta-row{font-size:12px;color:var(--muted)}
.history-detail{margin-top:10px;padding-top:10px;border-top:1px dashed var(--border)}
.history-detail .item{
  background:var(--bg);border:1px solid var(--border);border-radius:8px;
  padding:8px 10px;margin-bottom:6px;font-size:12px;
}
.history-detail .item.correct{border-color:rgba(16,185,129,.35)}
.history-detail .item.wrong{border-color:rgba(239,68,68,.35)}
.history-detail .meta-row{color:var(--muted);margin-top:4px;line-height:1.6}
.modal-card{
  background:var(--panel);border:1px solid var(--border);border-radius:14px;
  padding:22px;max-width:480px;width:100%;box-shadow:var(--shadow);
  max-height:90vh;overflow:auto;
}
.modal-card h2{margin:0 0 6px}
.field{display:flex;flex-direction:column;gap:6px;margin:14px 0}
.field span:first-child{font-size:13px;color:var(--muted);font-weight:500}
.field input,.field select{
  padding:9px 10px;border:1px solid var(--border);background:var(--bg);
  color:var(--text);border-radius:8px;font-size:14px;
}
.field input:focus,.field select:focus{outline:none;border-color:var(--primary)}
.field .hint{color:var(--muted);font-size:12px}
.field a.hint{color:var(--primary-2)}
.field a.hint:hover{text-decoration:underline}

/* result */
.stats{display:grid;grid-template-columns:repeat(4,1fr);gap:12px;margin:14px 0 18px}
.stat{background:var(--panel-2);border:1px solid var(--border);border-radius:10px;padding:14px;text-align:center}
.stat .num{font-size:24px;font-weight:600}
.stat .lbl{font-size:12px;color:var(--muted);margin-top:4px}
.stat.big .num{color:var(--primary-2)}

.kpstats{margin:8px 0 18px}
.kpstat{
  display:grid;grid-template-columns:140px 1fr 70px;gap:10px;align-items:center;
  padding:6px 0;border-bottom:1px dashed var(--border);font-size:13px;
}
.kpstat .kpname{color:var(--text)}
.kpstat .kpbar{height:6px;background:var(--border);border-radius:3px;overflow:hidden}
.kpstat .kpbar > div{height:100%;background:var(--good)}
.kpstat .kprate{text-align:right;color:var(--muted)}

.review{margin-top:8px}
.review h3{margin-bottom:8px}
.review .item{
  background:var(--panel-2);border:1px solid var(--border);border-radius:10px;
  padding:10px 12px;margin-bottom:8px;
}
.review .item.correct{border-color:rgba(16,185,129,.4)}
.review .item.wrong  {border-color:rgba(239,68,68,.4)}
.review .row1{display:flex;justify-content:space-between;gap:8px;margin-bottom:4px}
.review .qstem{font-weight:500}
.review .meta-row{font-size:12px;color:var(--muted);margin-top:4px}

@media (max-width:720px){
  .topbar{padding:10px 14px;padding-top:max(10px,env(safe-area-inset-top))}
  .brand{font-size:14px}
  .meta{font-size:12px;gap:8px}
  main{margin:14px auto;padding:0 10px;padding-bottom:calc(110px + env(safe-area-inset-bottom))}
  .card{padding:16px;border-radius:12px}
  h1{font-size:18px}
  h2{font-size:16px}
  .stem{font-size:16px}

  .grid{grid-template-columns:1fr;gap:12px;margin:12px 0}
  .stats{grid-template-columns:repeat(2,1fr)}
  .kpstat{grid-template-columns:90px 1fr 60px;font-size:12px}
  .chips.kp{max-height:140px}

  .dropzone{padding:32px 12px}
  .dz-icon{font-size:28px}
  .dz-title{font-size:14px}

  .option{padding:14px 12px}
  .option .label{flex:0 0 32px;height:32px;line-height:32px}

  .qheader{flex-wrap:wrap;gap:8px}
  .qtags{order:3;width:100%}

  /* 底部固定操作栏，方便单手操作 */
  .quiz .actions{
    position:fixed;left:0;right:0;bottom:0;z-index:20;
    margin:0;padding:10px 12px;
    padding-bottom:calc(10px + env(safe-area-inset-bottom));
    background:linear-gradient(180deg,rgba(15,23,42,.6),rgba(15,23,42,.96) 30%);
    backdrop-filter:blur(10px);-webkit-backdrop-filter:blur(10px);
    border-top:1px solid var(--border);
    justify-content:space-between;
  }
  .quiz .actions button{flex:1;min-height:44px;padding:10px 12px;font-size:15px}
  .quiz .actions button.ghost{flex:0 0 auto;min-width:80px}

  /* 触控目标 */
  .chip{padding:8px 14px;font-size:14px}
  button.primary,button.ghost{min-height:42px}
  input[type=number]{font-size:16px;min-height:42px} /* iOS 16px 防自动缩放 */
}

@media (max-width:380px){
  .stats{grid-template-columns:repeat(2,1fr)}
  .stat .num{font-size:20px}
  .qtags .tag{font-size:11px;padding:2px 6px}
}

/* 快捷筛选 */
.quick-filters{display:flex;gap:8px;margin:14px 0 10px;flex-wrap:wrap}
.qf{
  padding:8px 14px;border-radius:999px;border:1px solid var(--border);
  background:var(--chip);color:var(--text);font-size:13px;cursor:pointer;
  transition:all .15s;
}
.qf:hover{border-color:var(--primary-2)}
.qf.active{background:var(--primary);border-color:var(--primary);color:#fff}
.qf-eb.active{background:#ef4444;border-color:#ef4444}
.qf-star.active{background:#f59e0b;border-color:#f59e0b}

/* 收藏星标按钮 */
.stem{display:flex;align-items:flex-start;gap:8px}
.stem #q-stem{flex:1;min-width:0}
.star-btn{
  flex:0 0 auto;background:none;border:0;color:var(--muted);
  font-size:24px;line-height:1;cursor:pointer;padding:2px 8px;
  border-radius:6px;transition:all .15s;
}
.star-btn:hover{color:#fbbf24}
.star-btn.starred{color:#fbbf24}