:root{
  --bg:#f4f6f9; --card:#fff; --line:#e8ebf0; --text:#1b1f26; --muted:#77808f;
  --brand:#2f6df6; --brand-2:#1b52d0; --soft:#eaf0ff;
  --chat:#16a34a; --chat-2:#12833c; --chat-soft:#e9f8ef;
  --warn:#c2410c; --warn-bg:#fdf1e6; --bad:#b91c1c; --bad-bg:#fdecec; --ok:#15803d;
  --r:16px; --nav-h:64px;
}
*{box-sizing:border-box;-webkit-tap-highlight-color:transparent}
html,body{height:100%}
body{margin:0;background:var(--bg);color:var(--text);
  font:16px/1.6 -apple-system,BlinkMacSystemFont,"PingFang SC","Microsoft YaHei",sans-serif;
  -webkit-font-smoothing:antialiased}
.hidden{display:none!important}
button{font:inherit;color:inherit;cursor:pointer;border:0;background:none}
input,textarea{font:inherit;color:var(--text)}

/* ---------- 登录 ---------- */
.login-wrap{min-height:100vh;display:flex;flex-direction:column;align-items:center;justify-content:center;padding:24px}
.login-banner{width:100%;margin:0}
.login-banner svg{display:block;width:100%;height:auto}
.login-body{padding:26px 24px 30px}
.login-card{background:var(--card);border-radius:22px;padding:0;width:100%;max-width:420px;
  box-shadow:0 12px 40px rgba(20,30,60,.08);overflow:hidden}
.login-card h1{margin:0 0 6px;font-size:24px}
.login-card .sub{margin:0 0 22px;color:var(--muted);font-size:14px}
label{display:block;margin-bottom:14px;font-size:14px;color:var(--muted)}
input,textarea{width:100%;padding:14px;border:1px solid var(--line);border-radius:12px;
  background:#fafbfd;outline:none;-webkit-appearance:none}
input:focus,textarea:focus{border-color:var(--brand);background:#fff}

.btn{display:inline-flex;align-items:center;justify-content:center;gap:6px;
  min-height:44px;padding:0 18px;border-radius:12px;border:1px solid var(--line);
  background:#fff;font-size:15px;font-weight:500}
.btn:active{transform:scale(.985)}
.btn.primary{background:var(--brand);border-color:var(--brand);color:#fff}
.btn.primary:active{background:var(--brand-2)}
.btn.big{min-height:50px;font-size:16px;border-radius:14px}
.btn.block{width:100%}
.chip-btn{min-height:34px;padding:0 12px;border-radius:20px;background:#f1f3f8;color:var(--muted);font-size:13px}
.msg{display:block;margin-top:10px;font-size:13px;color:var(--warn)}

/* ---------- 顶栏 ---------- */
.top{position:sticky;top:0;z-index:30;display:flex;align-items:center;justify-content:space-between;
  gap:10px;padding:calc(12px + env(safe-area-inset-top)) 16px 12px;
  background:rgba(255,255,255,.96);backdrop-filter:blur(10px);border-bottom:1px solid var(--line)}
.who{display:flex;flex-direction:column;min-width:0}
.who b{font-size:19px;line-height:1.3}
.who span{font-size:12px;color:var(--muted)}
.top-right{display:flex;align-items:center;gap:8px;flex:0 0 auto}
.pts{background:var(--soft);color:var(--brand);font-size:14px;font-weight:600;
  padding:6px 12px;border-radius:20px;white-space:nowrap}

/* ---------- 主区 ---------- */
main{padding:14px 14px calc(var(--nav-h) + 28px + env(safe-area-inset-bottom))}
.view{display:none}
.view.active{display:block;animation:fade .18s ease}
@keyframes fade{from{opacity:.5;transform:translateY(4px)}to{opacity:1;transform:none}}
.card{background:var(--card);border-radius:var(--r);padding:18px;margin-bottom:14px;
  box-shadow:0 1px 3px rgba(20,30,60,.05)}
.card h3{margin:0 0 12px;font-size:17px}
.hint{color:var(--muted);font-size:13px;margin:8px 0 0}
.hint.center{text-align:center}
.hint.tiny{font-size:12px;margin-top:6px}
.mb8{margin-bottom:8px}

/* 概况 */
.hero{padding:22px 20px}
.hero-name{font-size:26px;font-weight:600;letter-spacing:.5px}
.hero-meta{color:var(--muted);font-size:13px;margin-top:4px}
.stats{display:grid;grid-template-columns:repeat(4,1fr);gap:8px;margin-top:18px}
.stats div{background:#f7f9fc;border-radius:12px;padding:12px 6px;text-align:center}
.stats b{display:block;font-size:22px;line-height:1.2}
.stats span{font-size:12px;color:var(--muted)}
.action-row{display:grid;grid-template-columns:1fr 1fr;gap:10px;margin-bottom:10px}
.tip{padding:16px 18px}
.tip-t{font-size:13px;color:var(--muted);margin-bottom:6px}
.tip-b{font-size:15px;line-height:1.65}

/* 掌握度 */
.bars{margin-top:2px}
.bar-row{display:flex;align-items:center;gap:10px;margin-bottom:10px;font-size:14px}
.bar-row .lb{flex:0 0 72px;color:var(--muted)}
.bar{flex:1;height:10px;border-radius:6px;background:#eef1f6;overflow:hidden}
.bar i{display:block;height:100%;border-radius:6px}
.bar-row .n{flex:0 0 38px;text-align:right;font-variant-numeric:tabular-nums;font-weight:600}
.sec-t{display:flex;align-items:center;gap:8px;font-size:15px;font-weight:600;margin:0 0 12px}
.sec-t .cnt{background:#f1f3f8;color:var(--muted);font-size:12px;font-weight:500;padding:2px 9px;border-radius:20px}
.kp{display:flex;justify-content:space-between;gap:12px;padding:12px 0;border-bottom:1px solid #f2f4f8}
.kp:last-child{border-bottom:0;padding-bottom:0}
.kp .k{font-size:15px;line-height:1.5}
.kp .u{font-size:12px;color:var(--muted);margin-top:2px}
.kp .e{flex:0 0 auto;font-size:12px;color:var(--muted);background:#f7f9fc;border-radius:20px;padding:2px 10px;height:22px;line-height:18px}
.more-btn{display:block;width:100%;margin-top:12px;min-height:42px;border-radius:12px;background:#f7f9fc;color:var(--brand);font-size:14px}

/* 错题 / 卷子 */
.list-head{display:flex;align-items:center;justify-content:space-between;margin:4px 4px 10px}
.list-head h3{margin:0;font-size:18px}
.list-head .sub{font-size:13px;color:var(--muted);font-weight:400;margin-left:8px}
.stack{display:flex;flex-direction:column;gap:10px}
.item{background:var(--card);border-radius:14px;padding:14px 16px;box-shadow:0 1px 3px rgba(20,30,60,.05)}
.item .h{display:flex;align-items:center;gap:8px;flex-wrap:wrap}
.tag{font-size:12px;background:#f1f3f8;color:var(--muted);border-radius:20px;padding:2px 10px}
.tag.blue{background:var(--soft);color:var(--brand)}
.tag.red{background:var(--bad-bg);color:var(--bad)}
.item .t{font-size:15px;margin-top:8px;line-height:1.6}
.item .p{font-size:13px;color:var(--muted);margin-top:6px}
.item .more{display:none;margin-top:12px;padding-top:12px;border-top:1px dashed var(--line);
  font-size:14px;line-height:1.7;color:#333}
.item.open .more{display:block}
.more dt{color:var(--muted);font-size:12px;margin-top:8px}
.more dd{margin:2px 0 0}
.item .toggle{margin-top:10px;font-size:13px;color:var(--brand)}
.paper{display:flex;align-items:center;gap:14px}
.paper .ico{flex:0 0 44px;height:44px;border-radius:12px;background:var(--soft);color:var(--brand);
  display:flex;align-items:center;justify-content:center;font-size:13px;font-weight:600}
.paper .info{flex:1;min-width:0}
.paper .nm{font-size:15px;line-height:1.45;word-break:break-all}
.paper .mt{font-size:12px;color:var(--muted);margin-top:3px}
.paper .btn{min-height:40px;padding:0 16px}

/* 分页 */
.pager{display:flex;align-items:center;justify-content:center;gap:14px;margin:16px 0 4px}
.pager button{min-height:42px;padding:0 20px;border-radius:12px;background:#fff;
  border:1px solid var(--line);font-size:15px}
.pager button:disabled{opacity:.4}
.pager .pi{font-size:14px;color:var(--muted);font-variant-numeric:tabular-nums}

/* 聊天 */
.chat-view{padding-bottom:calc(var(--nav-h) + 8px + env(safe-area-inset-bottom))}
.chat-box{min-height:calc(100vh - 330px);display:flex;flex-direction:column;gap:10px;
  padding:6px 2px 10px;overflow-y:auto}
.bubble{max-width:84%;padding:12px 15px;border-radius:16px;font-size:15px;line-height:1.6;
  white-space:pre-wrap;word-break:break-word}
.bubble.parent{align-self:flex-end;background:var(--chat);color:#fff;border-bottom-right-radius:5px}
.bubble.teacher{align-self:flex-start;background:#fff;border:1px solid #d9eee2;border-bottom-left-radius:5px;
  box-shadow:0 1px 3px rgba(20,30,60,.05)}
.bubble.system{align-self:center;background:var(--chat-soft);color:#4a7b60;font-size:13px;max-width:92%;text-align:center}
.bubble .t{display:block;font-size:11px;opacity:.55;margin-top:6px}
.quick{display:flex;gap:8px;overflow-x:auto;padding:8px 0;margin-bottom:8px}
.quick button{flex:0 0 auto;min-height:38px;padding:0 14px;border-radius:20px;background:#fff;
  border:1px solid #d9eee2;font-size:14px;color:#2f6b4c}
.chat-input{display:flex;gap:8px;align-items:flex-end;background:#fff;border:1px solid #d9eee2;
  border-radius:16px;padding:8px;box-shadow:0 2px 10px rgba(20,90,60,.06)}
.chat-input textarea{flex:1;border:0;background:none;resize:none;max-height:110px;padding:9px 6px;font-size:15px}
.send{flex:0 0 auto;min-height:44px;padding:0 20px;border-radius:12px;background:var(--chat);
  color:#fff;font-size:15px;font-weight:500}
.send:active{background:var(--chat-2)}
.mic{flex:0 0 46px;height:46px;border-radius:12px;background:var(--chat-soft);color:var(--chat);
  font-size:19px;border:1px solid #d9eee2}
.mic.rec{background:var(--bad);border-color:var(--bad);color:#fff;animation:pulse 1s infinite}
@keyframes pulse{50%{opacity:.55}}

/* 管理 */
.row{display:flex;gap:8px;margin-bottom:8px}
.short{flex:1}

/* 底部导航 */
.bottom-nav{position:fixed;left:0;right:0;bottom:0;z-index:40;display:flex;
  height:calc(var(--nav-h) + env(safe-area-inset-bottom));
  padding-bottom:env(safe-area-inset-bottom);
  background:rgba(255,255,255,.97);backdrop-filter:blur(12px);border-top:1px solid var(--line)}
.bottom-nav button{flex:1;display:flex;flex-direction:column;align-items:center;justify-content:center;
  gap:3px;font-size:12px;color:var(--muted)}
.bottom-nav button i{font-style:normal;font-size:17px;line-height:1}
.bottom-nav button.active{color:var(--brand);font-weight:600}
.bottom-nav button[data-tab="chat"].active{color:var(--chat)}

/* ---------- 平板 / 电脑：居中收窄、导航移到顶部，像普通网页一样按比例呈现 ---------- */
@media (min-width: 720px){
  html, body{background:#e8ecf2}
  #appView{max-width:820px;margin:0 auto;background:var(--bg);min-height:100vh;
    display:flex;flex-direction:column;box-shadow:0 0 60px rgba(20,30,60,.10)}
  .top{order:1}
  .bottom-nav{order:2;position:static;left:auto;bottom:auto;transform:none;
    height:auto;width:auto;max-width:none;padding:6px 10px;gap:4px;
    justify-content:center;flex-wrap:wrap;border-radius:0;box-shadow:none;
    border-top:0;border-bottom:1px solid var(--line)}
  .bottom-nav button{flex:0 0 auto;flex-direction:row;gap:7px;min-height:40px;
    padding:0 18px;border-radius:10px;font-size:15px}
  .bottom-nav button i{font-size:15px}
  .bottom-nav button.active{background:var(--soft)}
  .bottom-nav button[data-tab="chat"].active{background:var(--chat-soft)}
  main{order:3;padding:18px 22px 48px}
  body{font-size:16.5px}
  .hero-name{font-size:28px}
  .stats b{font-size:24px}
  .card{padding:20px 22px}
  .login-card{max-width:430px}
  .chat-view{padding-bottom:8px}
  .chat-box{min-height:calc(100vh - 330px)}
}
@media (min-width: 1200px){
  #appView{max-width:880px}
}

/* ---------- 扣分提示 ---------- */
.toast{position:fixed;left:50%;bottom:calc(var(--nav-h) + 18px);transform:translateX(-50%);
  z-index:120;background:rgba(20,28,45,.92);color:#fff;font-size:14px;line-height:1.5;
  padding:10px 16px;border-radius:12px;max-width:88vw;text-align:center;
  box-shadow:0 8px 24px rgba(15,23,42,.28);opacity:1;transition:opacity .45s, transform .45s}
.toast.out{opacity:0;transform:translateX(-50%) translateY(8px)}
@media (min-width: 900px){
  .toast{bottom:28px}
}

/* ---------- 管理总览 ---------- */
.stu{padding:12px 0;border-bottom:1px solid var(--line)}
.stu:last-child{border-bottom:0}
.stu .k{font-size:15px;font-weight:600;display:flex;align-items:center;gap:8px;flex-wrap:wrap}
.stu .u{font-size:13px;color:var(--muted);margin-top:4px}
.stu .bar{height:7px;border-radius:6px;background:#eef1f6;overflow:hidden;margin:8px 0 4px}
.stu .bar i{display:block;height:100%;background:var(--brand);border-radius:6px}
.log{font-size:13px;line-height:1.9;color:#4b5563;white-space:pre-line;overflow-x:auto}

/* ---------- 学科切换 ---------- */
.subj-bar{display:flex;gap:8px;padding:10px 14px 4px;overflow-x:auto}
.subj-bar::-webkit-scrollbar{display:none}
.subj{flex:0 0 auto;border:1px solid var(--line);background:#fff;color:#4b5563;
  font-size:14px;padding:7px 16px;border-radius:18px;cursor:pointer}
.subj.on{background:var(--brand);border-color:var(--brand);color:#fff;font-weight:600}
.subj:active{transform:scale(.97)}
.subj.dis{background:#f3f4f6;border-color:#e5e7eb;color:#9ca3af;cursor:default}
.subj.dis:active{transform:none}

/* ---------- 学习时间轴 ---------- */
#bookBar{display:flex;gap:16px;padding:6px 14px 8px;overflow-x:auto;align-items:flex-end}
#bookBar::-webkit-scrollbar{display:none}
.tl-group{display:flex;flex-direction:column;align-items:center;flex:0 0 auto}
.tl-stage{font-size:11px;color:#9ca3af;margin-bottom:2px}
.tl-nodes{display:flex;align-items:flex-end;gap:8px;position:relative;padding-bottom:2px}
.tl-nodes::before{content:'';position:absolute;left:-4px;right:-4px;bottom:9px;height:2px;background:#e5e7eb}
.tl-node{position:relative;z-index:1;display:flex;flex-direction:column;align-items:center;
  background:none;border:0;padding:0;min-width:12px;cursor:default}
button.tl-node{cursor:pointer}
.tl-lbl{font-size:10px;color:#6b7280;height:14px;line-height:14px;white-space:nowrap}
.tl-dot{width:8px;height:8px;border-radius:50%;background:#d1d5db;margin-bottom:4px}
.tl-dot.data{background:var(--brand)}
.tl-dot.cur{width:12px;height:12px;background:var(--brand);box-shadow:0 0 0 3px rgba(47,109,246,.18)}
.tl-node.sel .tl-lbl{color:var(--brand);font-weight:600}
button.tl-node:active .tl-dot{transform:scale(.9)}

/* ---------- 知识图谱（竖向树） ---------- */
.legend{display:flex;gap:14px;flex-wrap:wrap;font-size:12px;color:#6b7280;margin:2px 0 12px}
.legend i{display:inline-block;width:10px;height:10px;border-radius:50%;margin-right:4px;vertical-align:-1px}
.kmap{position:relative;padding-left:20px}
.kmap::before{content:'';position:absolute;left:5px;top:6px;bottom:6px;width:2.5px;border-radius:2px;background:#dbe4f0}
.km-root{position:relative;font-size:14px;font-weight:700;color:#2f6df6;margin:4px 0 2px}
.km-r-dot{position:absolute;left:-20px;top:4px;width:11px;height:11px;border-radius:50%;background:#2f6df6;box-shadow:0 0 0 3px rgba(47,109,246,.18)}
.km-dom{position:relative;margin:16px 0 8px}
.km-d-dot{position:absolute;left:-19px;top:9px;width:9px;height:9px;border-radius:50%;background:#2f6df6}
.km-dom-pill{display:inline-block;background:#2f6df6;color:#fff;font-size:13px;font-weight:600;padding:4px 14px;border-radius:14px}
.km-units{position:relative;margin-left:6px;padding-left:14px}
.km-units::before{content:'';position:absolute;left:0;top:0;bottom:2px;width:2px;background:#e8edf5;border-radius:2px}
.km-unit{position:relative;font-size:13.5px;font-weight:600;color:#1f2937;margin:12px 0 6px;display:flex;align-items:center;gap:7px;flex-wrap:wrap}
.km-u-dot{flex:0 0 auto;width:9px;height:9px;border-radius:50%;background:#94a3b8;margin-left:-19px}
.km-u-dot.weak{background:#f59e0b;box-shadow:0 0 0 3px rgba(245,158,11,.22)}
.km-u-dot.bad{background:#ef4444;box-shadow:0 0 0 3px rgba(239,68,68,.22)}
.km-u-tip{font-size:11px;font-weight:500;color:#92400e;background:#fef3c7;border-radius:9px;padding:2px 8px}
.km-pts{display:flex;flex-wrap:wrap;gap:6px;padding-left:0;margin-bottom:4px}
.km-pt{font-size:12px;line-height:1.35;padding:4px 10px;border-radius:12px;background:#f3f4f6;color:#4b5563;border:1px solid #e5e7eb}
.km-pt.weak{background:#fef3c7;color:#92400e;border-color:#fcd34d;font-weight:600}
.km-pt.bad{background:#fee2e2;color:#b91c1c;border-color:#fca5a5;font-weight:600}
.km-pt.ok{background:#d1fae5;color:#065f46;border-color:#6ee7b7}

/* ---------- 更早的记录 ---------- */
.chat-more-wrap{text-align:center;margin:6px 0 10px}
.chat-more{border:1px solid var(--line);background:#fff;color:#6b7280;font-size:12px;
  padding:6px 16px;border-radius:14px;cursor:pointer}
.chat-more:active{background:#f3f4f6}