:root{
  --bg:#F2F5FA; --card:#FFFFFF; --ink:#16202F; --sub:#3D4A5C; --muted:#8A97AB; --line:#E7ECF3;
  --brand:#3B6EF6; --brand-soft:#EAF1FF; --teal:#12A594; --teal-soft:#E6F6F3;
  --orange:#F08A24; --orange-soft:#FFF3E4; --purple:#7A5AF8; --purple-soft:#F0ECFF;
  --red:#E5484D; --red-soft:#FDECEC; --green:#2FA84F; --green-soft:#E9F7EE;
  --gold:#E8B33A; --shadow:0 2px 10px rgba(22,32,47,.06); --shadow-lg:0 8px 30px rgba(22,32,47,.12);
  --r:14px;
}
*{box-sizing:border-box;-webkit-tap-highlight-color:transparent}
html,body{margin:0;padding:0}
body{background:var(--bg);color:var(--ink);font-family:-apple-system,BlinkMacSystemFont,"PingFang SC","Microsoft YaHei","Helvetica Neue",Arial,sans-serif;font-size:14px;line-height:1.6}
button,input,textarea,select{font-family:inherit;font-size:inherit;color:inherit}
a{color:var(--brand);text-decoration:none}
::-webkit-scrollbar{width:7px;height:7px}
::-webkit-scrollbar-thumb{background:#D3DAE5;border-radius:8px}
::-webkit-scrollbar-track{background:transparent}

/* ===== 顶栏 ===== */
.topbar{position:sticky;top:0;z-index:60;background:rgba(255,255,255,.94);backdrop-filter:blur(10px);border-bottom:1px solid var(--line);display:flex;align-items:center;gap:12px;padding:10px 18px;flex-wrap:wrap}
.brand{display:flex;align-items:center;gap:9px;font-weight:800;letter-spacing:-.2px}
.brand .logo{width:30px;height:30px;border-radius:9px;background:linear-gradient(135deg,var(--brand),var(--purple));color:#fff;display:grid;place-items:center;font-size:15px;font-weight:700}
.brand small{display:block;font-size:10.5px;color:var(--muted);font-weight:600;letter-spacing:0}
.seg{display:flex;background:#EEF2F8;border-radius:11px;padding:3px;gap:2px}
.seg button{border:0;background:transparent;padding:6px 16px;border-radius:9px;font-size:13px;font-weight:700;color:var(--muted);cursor:pointer}
.seg button.on{background:#fff;color:var(--brand);box-shadow:var(--shadow)}
.topbar .spacer{flex:1}
.mini-switch{display:flex;align-items:center;gap:6px;font-size:12px;color:var(--sub);background:#F5F8FC;border:1px solid var(--line);padding:5px 10px;border-radius:20px;cursor:pointer;user-select:none}
.mini-switch .sw{width:32px;height:18px;border-radius:20px;background:#CBD5E3;position:relative;transition:.2s}
.mini-switch .sw i{position:absolute;top:2px;left:2px;width:14px;height:14px;border-radius:50%;background:#fff;transition:.2s}
.mini-switch.on .sw{background:var(--teal)}
.mini-switch.on .sw i{left:16px}
.demo-btn{border:1px dashed var(--orange);background:var(--orange-soft);color:var(--orange);border-radius:20px;padding:5px 12px;font-size:12px;font-weight:700;cursor:pointer}

/* ===== 布局 ===== */
.wrap{max-width:1240px;margin:0 auto;padding:16px 18px 60px}
.phone{max-width:436px;margin:0 auto;background:var(--bg)}
.panel{background:var(--card);border:1px solid var(--line);border-radius:var(--r);box-shadow:var(--shadow)}
.pad{padding:14px}
.h-title{font-size:16px;font-weight:800;margin:0 0 2px}
.h-sub{font-size:12px;color:var(--muted);margin:0}

/* ===== 学生端底部 tab ===== */
.tabbar{position:fixed;left:50%;transform:translateX(-50%);bottom:0;width:436px;max-width:100%;background:rgba(255,255,255,.97);backdrop-filter:blur(10px);border-top:1px solid var(--line);display:flex;z-index:50;padding-bottom:env(safe-area-inset-bottom)}
.tabbar button{flex:1;border:0;background:transparent;padding:8px 0 7px;display:flex;flex-direction:column;align-items:center;gap:2px;font-size:10.5px;color:var(--muted);cursor:pointer;font-weight:600}
.tabbar button .ic{font-size:19px;line-height:1}
.tabbar button.on{color:var(--brand)}
.tabbar button.on .ic{transform:translateY(-1px)}

/* ===== 通用元件 ===== */
.card{background:var(--card);border:1px solid var(--line);border-radius:var(--r);box-shadow:var(--shadow);padding:14px;margin-bottom:12px}
.card h3{margin:0 0 8px;font-size:14px;font-weight:800;display:flex;align-items:center;gap:6px}
.card h3 .dot{width:6px;height:6px;border-radius:50%;background:var(--brand);display:inline-block}
.tag{display:inline-block;font-size:11px;font-weight:700;padding:2px 8px;border-radius:20px;background:var(--brand-soft);color:var(--brand)}
.tag.g{background:var(--green-soft);color:var(--green)}
.tag.o{background:var(--orange-soft);color:var(--orange)}
.tag.p{background:var(--purple-soft);color:var(--purple)}
.tag.r{background:var(--red-soft);color:var(--red)}
.tag.t{background:var(--teal-soft);color:var(--teal)}
.tag.gray{background:#F0F3F8;color:var(--muted)}
.btn{border:0;border-radius:11px;padding:10px 16px;font-size:13.5px;font-weight:700;cursor:pointer;background:var(--brand);color:#fff;transition:.15s}
.btn:hover{filter:brightness(1.05)}
.btn:active{transform:scale(.98)}
.btn.ghost{background:#fff;color:var(--sub);border:1px solid var(--line)}
.btn.teal{background:var(--teal)}
.btn.orange{background:var(--orange)}
.btn.purple{background:var(--purple)}
.btn.red{background:var(--red)}
.btn.green{background:var(--green)}
.btn.sm{padding:6px 12px;font-size:12px;border-radius:9px}
.btn.lg{padding:13px 20px;font-size:15px;width:100%}
.btn:disabled{opacity:.45;cursor:not-allowed}
.btn-row{display:flex;gap:8px;flex-wrap:wrap}
.chip{border:1px solid var(--line);background:#fff;border-radius:20px;padding:5px 11px;font-size:12px;cursor:pointer;color:var(--sub);font-weight:600}
.chip.on{background:var(--brand);border-color:var(--brand);color:#fff}
.chip.on.t{background:var(--teal);border-color:var(--teal)}
.muted{color:var(--muted)}
.small{font-size:12px}
.xs{font-size:11px}
.center{text-align:center}
.row{display:flex;align-items:center;gap:8px}
.between{display:flex;align-items:center;justify-content:space-between;gap:8px}
.grid2{display:grid;grid-template-columns:1fr 1fr;gap:10px}
.grid3{display:grid;grid-template-columns:repeat(3,1fr);gap:10px}
.grid4{display:grid;grid-template-columns:repeat(4,1fr);gap:10px}
textarea,input[type=text],input[type=number],select{width:100%;border:1px solid var(--line);background:#FBFCFE;border-radius:11px;padding:10px 12px;outline:none;resize:vertical}
textarea:focus,input:focus,select:focus{border-color:var(--brand);background:#fff}
.wrap-rel{position:relative}
.mic-fab{position:absolute;right:9px;bottom:9px;width:30px;height:30px;border-radius:50%;border:0;background:var(--brand);color:#fff;font-size:14px;cursor:pointer;box-shadow:var(--shadow)}
.mic-fab.rec{background:var(--red);animation:pulse 1s infinite}
@keyframes pulse{0%{box-shadow:0 0 0 0 rgba(229,72,77,.5)}70%{box-shadow:0 0 0 10px rgba(229,72,77,0)}100%{box-shadow:0 0 0 0 rgba(229,72,77,0)}}
.speak-mini{border:0;background:var(--teal-soft);color:var(--teal);border-radius:8px;width:26px;height:26px;cursor:pointer;font-size:13px;flex:none}
.bar{height:8px;border-radius:8px;background:#EDF1F7;overflow:hidden}
.bar>i{display:block;height:100%;border-radius:8px;background:linear-gradient(90deg,var(--brand),var(--purple))}
.bar.g>i{background:linear-gradient(90deg,#34C77B,var(--teal))}
.bar.o>i{background:linear-gradient(90deg,#F5B14A,var(--orange))}
.divider{height:1px;background:var(--line);margin:12px 0}
.empty{text-align:center;color:var(--muted);padding:36px 10px;font-size:13px}

/* 步骤条 */
.steps{display:flex;align-items:center;gap:6px;margin-bottom:12px}
.steps .st{flex:1;text-align:center;font-size:11px;font-weight:700;color:var(--muted)}
.steps .st .num{width:26px;height:26px;border-radius:50%;background:#EDF1F7;color:var(--muted);display:grid;place-items:center;margin:0 auto 4px;font-size:12px}
.steps .st.on .num{background:var(--brand);color:#fff}
.steps .st.done .num{background:var(--green);color:#fff}
.steps .st.done{color:var(--green)}
.steps .st.on{color:var(--brand)}

/* 聊天气泡 */
.chat{display:flex;flex-direction:column;gap:10px}
.bbl{max-width:86%;padding:10px 13px;border-radius:14px;font-size:13.5px;position:relative;line-height:1.65}
.bbl.ai{background:#F3F6FB;border-top-left-radius:4px;align-self:flex-start}
.bbl.me{background:var(--brand);color:#fff;border-top-right-radius:4px;align-self:flex-end}
.bbl.role{background:var(--purple-soft);border-top-left-radius:4px;align-self:flex-start}
.bbl .who{font-size:11px;font-weight:800;margin-bottom:3px;opacity:.85}
.bbl .foot{display:flex;gap:6px;align-items:center;margin-top:5px}
.typing{display:inline-flex;gap:3px;align-items:center}
.typing i{width:5px;height:5px;border-radius:50%;background:var(--muted);animation:bounce 1s infinite}
.typing i:nth-child(2){animation-delay:.15s}.typing i:nth-child(3){animation-delay:.3s}
@keyframes bounce{0%,80%,100%{transform:translateY(0)}40%{transform:translateY(-5px)}}

/* 提示卡 / 分析卡 */
.tip{background:var(--brand-soft);border-left:3px solid var(--brand);border-radius:0 10px 10px 0;padding:9px 12px;font-size:12.5px;color:var(--sub)}
.warn{background:var(--orange-soft);border-left:3px solid var(--orange);border-radius:0 10px 10px 0;padding:9px 12px;font-size:12.5px;color:var(--sub)}
.good{background:var(--green-soft);border-left:3px solid var(--green);border-radius:0 10px 10px 0;padding:9px 12px;font-size:12.5px;color:var(--sub)}
.encourage{background:linear-gradient(135deg,#FFF6E9,#FFEFF6);border:1px solid #FBE2C8;border-radius:12px;padding:12px 14px;font-size:13px;color:#7A4B12;display:flex;gap:9px;align-items:flex-start}
.dim-row{display:flex;align-items:center;gap:8px;margin-bottom:7px}
.dim-row .nm{width:64px;font-size:12px;color:var(--sub);flex:none}
.dim-row .bar{flex:1}
.dim-row .vl{width:34px;text-align:right;font-size:12px;font-weight:800}
.trans{background:#FAFBFD;border:1px solid var(--line);border-radius:11px;padding:10px 12px;font-size:12.5px}
.trans .ln{display:flex;gap:8px;padding:3px 0;border-bottom:1px dashed #EDF1F7}
.trans .ln:last-child{border:0}
.trans .tm{color:var(--muted);font-size:11px;width:38px;flex:none}

/* 视频区 */
.video-box{background:#0E1622;border-radius:12px;aspect-ratio:16/9;display:grid;place-items:center;color:#fff;position:relative;overflow:hidden}
.video-box video{width:100%;height:100%;object-fit:cover}
.video-box .ph{text-align:center;font-size:12px;color:#93A2B8;padding:20px}
.rec-dot{position:absolute;top:10px;left:10px;background:rgba(229,72,77,.9);color:#fff;font-size:11px;font-weight:800;padding:3px 9px;border-radius:20px;display:flex;align-items:center;gap:5px}
.rec-dot i{width:7px;height:7px;border-radius:50%;background:#fff;animation:pulse 1.2s infinite}

/* 教师端 */
.desk{display:grid;grid-template-columns:200px 1fr;gap:16px;align-items:start}
.side{background:var(--card);border:1px solid var(--line);border-radius:var(--r);padding:10px;box-shadow:var(--shadow);position:sticky;top:66px}
.side button{display:flex;align-items:center;gap:9px;width:100%;border:0;background:transparent;padding:10px 12px;border-radius:10px;font-size:13px;font-weight:700;color:var(--sub);cursor:pointer;margin-bottom:2px;text-align:left}
.side button.on{background:var(--brand-soft);color:var(--brand)}
.side .badge{margin-left:auto;background:var(--red);color:#fff;font-size:10px;padding:1px 6px;border-radius:20px}
.kpi{display:grid;grid-template-columns:repeat(5,1fr);gap:10px;margin-bottom:12px}
.kpi .k{background:var(--card);border:1px solid var(--line);border-radius:var(--r);padding:12px;box-shadow:var(--shadow)}
.kpi .k b{font-size:22px;display:block;line-height:1.2}
.kpi .k span{font-size:11.5px;color:var(--muted)}
table.tb{width:100%;border-collapse:collapse;font-size:12.5px}
table.tb th,table.tb td{padding:9px 10px;border-bottom:1px solid var(--line);text-align:left}
table.tb th{color:var(--muted);font-weight:700;font-size:11.5px;background:#FAFBFD}
table.tb tr:hover td{background:#FAFBFD}
.avatar{width:36px;height:36px;border-radius:50%;display:grid;place-items:center;font-weight:800;color:#fff;font-size:14px;flex:none}
.avatar.sm{width:28px;height:28px;font-size:12px}
.avatar.lg{width:52px;height:52px;font-size:19px}
.qitem{background:#FAFBFD;border:1px solid var(--line);border-radius:11px;padding:10px 12px;margin-bottom:8px}
.qitem .q{font-size:12.5px;font-weight:700;margin-bottom:4px}
.qitem .a{font-size:12.5px;color:var(--sub)}
.opt{border:1px solid var(--line);border-radius:11px;padding:10px 12px;margin-bottom:8px;cursor:pointer;background:#fff;font-size:13px}
.opt:hover{border-color:var(--brand)}
.opt.on{border-color:var(--brand);background:var(--brand-soft);font-weight:700}
.tl{position:relative;padding-left:18px}
.tl:before{content:'';position:absolute;left:5px;top:4px;bottom:4px;width:2px;background:var(--line)}
.tl .n{position:relative;margin-bottom:12px}
.tl .n:before{content:'';position:absolute;left:-17px;top:6px;width:9px;height:9px;border-radius:50%;background:var(--brand);border:2px solid #fff}
.tl .n .h{font-size:12px;font-weight:800}
.tl .n .b{font-size:12.5px;color:var(--sub)}
.wordcloud span{display:inline-block;margin:3px 5px 3px 0;padding:3px 10px;border-radius:20px;background:var(--purple-soft);color:var(--purple);font-size:12px;font-weight:700}
.wordcloud span.big{font-size:15px;background:var(--brand-soft);color:var(--brand)}
.wordcloud span.mid{font-size:13px}

/* 审核工作台 */
.review-top{display:grid;grid-template-columns:300px 1fr;gap:14px;align-items:start}
.review-left{position:sticky;top:66px}
.rtabs{display:flex;gap:4px;border-bottom:1px solid var(--line);margin-bottom:12px;flex-wrap:wrap}
.rtabs button{border:0;background:transparent;padding:8px 12px;font-size:13px;font-weight:700;color:var(--muted);cursor:pointer;border-bottom:2px solid transparent;margin-bottom:-1px}
.rtabs button.on{color:var(--brand);border-bottom-color:var(--brand)}
.rtabs.scroll{flex-wrap:nowrap;overflow-x:auto;scrollbar-width:none}
.rtabs.scroll::-webkit-scrollbar{display:none}
.rtabs.scroll button{flex:none;padding:8px 8px;font-size:12.5px}
.plan-edit{background:#FAFBFD;border:1px dashed var(--line);border-radius:12px;padding:12px}
.plan-edit label{font-size:11.5px;font-weight:800;color:var(--sub);display:block;margin:8px 0 4px}
.step-edit{display:flex;gap:6px;margin-bottom:6px;align-items:flex-start}
.step-edit .idx{width:22px;height:22px;border-radius:50%;background:var(--brand-soft);color:var(--brand);display:grid;place-items:center;font-size:11px;font-weight:800;flex:none;margin-top:6px}
.note-box{border:1px solid var(--line);border-radius:11px;padding:8px 10px;background:#fff;font-size:12.5px}
.quick span{cursor:pointer;border:1px solid var(--line);border-radius:20px;padding:3px 9px;font-size:11.5px;margin:0 5px 5px 0;display:inline-block;background:#fff;color:var(--sub)}
.quick span:hover{border-color:var(--teal);color:var(--teal)}
.logline{font-size:11.5px;color:var(--muted);padding:4px 0;border-bottom:1px dashed var(--line)}

/* 弹层 */
.mask{position:fixed;inset:0;background:rgba(16,24,36,.5);z-index:100;display:none;align-items:center;justify-content:center;padding:20px}
.mask.on{display:flex}
.modal{background:#fff;border-radius:16px;max-width:560px;width:100%;max-height:86vh;overflow:auto;box-shadow:var(--shadow-lg);padding:18px}
.drawer{position:fixed;top:0;right:0;bottom:0;width:520px;max-width:100%;background:var(--bg);z-index:110;transform:translateX(100%);transition:.25s;overflow:auto;box-shadow:-8px 0 30px rgba(0,0,0,.12)}
.drawer.on{transform:translateX(0)}
.drawer .dh{position:sticky;top:0;background:#fff;border-bottom:1px solid var(--line);padding:12px 14px;display:flex;align-items:center;gap:10px;z-index:5}
.toast{position:fixed;left:50%;transform:translateX(-50%);bottom:76px;background:rgba(22,32,47,.94);color:#fff;padding:10px 16px;border-radius:24px;font-size:12.5px;z-index:200;opacity:0;transition:.25s;pointer-events:none;max-width:88%;text-align:center}
.toast.on{opacity:1;bottom:88px}
.gain{position:fixed;left:50%;top:40%;transform:translateX(-50%);font-size:26px;font-weight:900;color:var(--orange);z-index:300;pointer-events:none;animation:fly 1.1s ease-out forwards}
@keyframes fly{0%{opacity:0;transform:translate(-50%,10px) scale(.7)}25%{opacity:1;transform:translate(-50%,-6px) scale(1.15)}100%{opacity:0;transform:translate(-50%,-52px) scale(1)}}
.spin{width:16px;height:16px;border:2px solid var(--line);border-top-color:var(--brand);border-radius:50%;animation:sp .7s linear infinite;display:inline-block;vertical-align:-3px;margin-right:6px}
@keyframes sp{to{transform:rotate(360deg)}}
.loading{text-align:center;color:var(--muted);font-size:12.5px;padding:18px 10px}
@media(max-width:900px){
  .desk{grid-template-columns:1fr}
  .side{position:static;display:flex;overflow:auto}
  .side button{width:auto;white-space:nowrap}
  .kpi{grid-template-columns:repeat(2,1fr)}
  .review-top{grid-template-columns:1fr}
  .review-left{position:static}
  .grid4{grid-template-columns:repeat(2,1fr)}
}
.chip{display:inline-block;font-size:12px;font-weight:700;padding:4px 11px;border-radius:20px;background:#F0F3F8;color:var(--muted);cursor:pointer;transition:.15s;border:1px solid transparent}
.chip:hover{background:var(--brand-soft);color:var(--brand)}
.chip.on{background:var(--brand);color:#fff}