/* ============================================================
 * 探索2「数据的传输过程」大闸蟹主题 · 共享样式
 * ============================================================ */
:root{
  --lake:#0e7490; --lake-d:#155e75; --lake-l:#e0f2f7; --lake-ll:#f2fafc;
  --crab:#ea580c; --crab-d:#c2410c; --crab-l:#ffedd5;
  --amber:#f59e0b; --amber-l:#fef3c7;
  --green:#16a34a; --green-l:#dcfce7;
  --red:#ef4444; --red-l:#fee2e2;
  --purple:#7c3aed; --purple-l:#ede9fe;
  --ink:#1e293b; --ink-2:#64748b; --line:#d9e6ea; --card:#ffffff;
  --r:14px;
}
*{box-sizing:border-box;margin:0;padding:0}
html{scroll-behavior:smooth}
body{font-family:"PingFang SC","Microsoft YaHei",system-ui,sans-serif;background:
  radial-gradient(1200px 500px at 20% -100px,#d6eef4 0,rgba(214,238,244,0) 60%),
  radial-gradient(900px 500px at 110% -80px,#fde8d9 0,rgba(253,232,217,0) 55%),
  linear-gradient(180deg,#eef7f9 0,#f6fbfc 420px,#fbfdfe 100%);color:var(--ink);min-height:100vh;padding-bottom:70px}
.wrap{max-width:1020px;margin:0 auto;padding:18px 16px 40px}

/* ---------- 顶部（顶部栏与导航合并、与正文同宽对齐） ---------- */
.topwrap{max-width:1020px;margin:0 auto;padding:10px 16px 8px;position:sticky;top:0;z-index:60;background:rgba(244,250,251,.93);backdrop-filter:blur(10px);-webkit-backdrop-filter:blur(10px);border-bottom:1px solid rgba(14,116,144,.08)}
.topbar{display:flex;align-items:center;gap:14px;flex-wrap:wrap;background:var(--card);border:1px solid var(--line);border-radius:16px;padding:12px 16px;box-shadow:0 4px 16px rgba(14,116,144,.1)}
.logo{width:48px;height:48px;border-radius:14px;background:linear-gradient(135deg,#ea580c,#f59e0b);display:flex;align-items:center;justify-content:center;font-size:26px;box-shadow:0 4px 12px rgba(234,88,12,.3);flex-shrink:0}
.topbar h1{font-size:20px;font-weight:800;line-height:1.2}
.topbar .sub{font-size:12px;color:var(--ink-2);margin-top:2px}
.userbar{margin-left:auto;display:flex;align-items:center;gap:8px;flex-wrap:wrap}
.userbar input{border:1.5px solid var(--line);border-radius:10px;padding:8px 10px;font-size:13px;outline:none;background:#fff;transition:border-color .15s}
.userbar input:focus{border-color:var(--lake)}
.in-group{width:74px;text-align:center;font-weight:700;letter-spacing:2px}
.in-name{width:110px}
.in-ip{width:200px;border:1.5px solid var(--line);border-radius:9px;padding:8px 10px;font-size:13px;font-family:Consolas,Menlo,monospace;outline:none;background:#fff}
.in-ip:focus{border-color:var(--lake)}
.wsdot{width:9px;height:9px;border-radius:50%;background:#cbd5e1;box-shadow:0 0 0 3px rgba(203,213,225,.3)}
.wsdot.on{background:#22c55e;box-shadow:0 0 0 3px rgba(34,197,94,.25)}
.wsdot.off{background:#ef4444;box-shadow:0 0 0 3px rgba(239,68,68,.2)}
.tbadge{background:linear-gradient(135deg,#7c3aed,#a855f7);color:#fff;font-size:11px;padding:2px 8px;border-radius:99px;font-weight:700}

/* ---------- 导航（并入顶部栏，等宽平铺、始终可见） ---------- */
.nav{display:flex;gap:6px;margin:0;flex-wrap:wrap}
.topbar .nav{flex:1 1 100%;margin-top:2px;padding-top:12px;border-top:1px dashed var(--line)}
.nav a{text-decoration:none;color:var(--ink-2);font-size:13px;font-weight:600;background:var(--lake-ll);border:1.5px solid var(--line);padding:8px 12px;border-radius:12px;transition:all .15s;flex:1 1 0;min-width:84px;text-align:center;white-space:nowrap}
.nav a:hover{border-color:var(--lake);color:var(--lake)}
.nav a.cur{background:var(--lake);border-color:var(--lake);color:#fff;box-shadow:0 3px 10px rgba(14,116,144,.25)}

/* ---------- 通用卡片 ---------- */
.card{background:var(--card);border:1px solid var(--line);border-radius:var(--r);padding:18px 20px;margin-bottom:16px;box-shadow:0 2px 10px rgba(15,23,42,.04)}
.card h3{font-size:16px;font-weight:800;margin-bottom:8px;display:flex;align-items:center;gap:8px}
.card h3 .tag{font-size:11px;background:var(--lake-l);color:var(--lake);padding:2px 8px;border-radius:99px;font-weight:600}
.hint{font-size:13px;color:var(--ink-2);line-height:1.8}
.hint b{color:var(--ink)}
.stepbar{display:flex;gap:6px;margin:14px 0 4px;flex-wrap:wrap}
.stepbar .st{flex:1;min-width:120px;font-size:12px;font-weight:700;color:var(--ink-2);background:var(--lake-ll);border:1.5px solid var(--line);border-radius:10px;padding:8px 10px;text-align:center;opacity:.7}
.stepbar .st.now{border-color:var(--crab);background:var(--crab-l);color:var(--crab-d);opacity:1;box-shadow:0 0 0 3px rgba(234,88,12,.12)}
.stepbar .st.done{background:var(--green-l);border-color:#86c79b;color:var(--green);opacity:1}
.stepbar .st .own{display:block;margin-top:3px;font-size:11px;font-weight:600;opacity:.88}
.stepbar .st.no-own{border-color:#e6a6a6;background:#fff3f3;color:#b42318}
.stepbar .st.now.no-own{box-shadow:0 0 0 3px rgba(180,35,24,.13)}

/* ---------- 按钮 ---------- */
.btn{border:none;border-radius:10px;padding:9px 16px;font-size:13.5px;cursor:pointer;font-weight:700;transition:transform .08s,box-shadow .15s,opacity .15s}
.btn:active{transform:scale(.96)}
.btn[disabled]{opacity:.5;cursor:not-allowed}
.btn-lake{background:var(--lake);color:#fff;box-shadow:0 3px 10px rgba(14,116,144,.25)}
.btn-crab{background:linear-gradient(135deg,#ea580c,#f97316);color:#fff;box-shadow:0 3px 10px rgba(234,88,12,.3)}
.btn-line{background:#fff;color:var(--lake);border:1.5px solid var(--lake)}
.btn-green{background:var(--green);color:#fff}
.btn-gray{background:#e2e8f0;color:#475569}
.btn-sm{padding:6px 12px;font-size:12.5px;border-radius:8px}

/* ---------- 通知条 ---------- */
.notice{display:none;padding:12px 16px;border-radius:12px;font-size:13.5px;line-height:1.7;margin-bottom:16px;font-weight:600}
.notice.show{display:block}
.notice.info{background:var(--lake-l);color:var(--lake-d);border:1px solid #b8dde8}
.notice.warn{background:var(--amber-l);color:#92400e;border:1px solid #fcd34d}
.notice.ok{background:var(--green-l);color:#166534;border:1px solid #86c79b}
.notice.err{background:var(--red-l);color:#b91c1c;border:1px solid #fca5a5}

/* ---------- 活动一：角色卡 ---------- */
.roles{display:grid;grid-template-columns:repeat(3,1fr);gap:12px;margin-top:12px}
.role{position:relative;border:1.5px solid var(--line);border-radius:var(--r);padding:14px 12px;text-align:center;background:#fff;transition:all .15s;cursor:pointer}
.role:hover{transform:translateY(-2px);box-shadow:0 6px 16px rgba(15,23,42,.08)}
.role .emoji{font-size:30px}
.role b{display:block;font-size:14px;margin:6px 0 4px;color:var(--ink)}
.role .desc{font-size:11.5px;color:var(--ink-2);line-height:1.5}
.role .who{font-size:11.5px;color:var(--crab-d);font-weight:700;margin-top:4px}
.role .stt{display:inline-block;margin-top:8px;font-size:11.5px;font-weight:700;padding:3px 10px;border-radius:99px}
.role .stt.free{background:var(--lake-l);color:var(--lake)}
.role .stt.mine{background:var(--crab-l);color:var(--crab-d)}
.role .stt.taken{background:#f1f5f9;color:#94a3b8}
.role.mine{border-color:var(--crab);box-shadow:0 0 0 3px rgba(234,88,12,.14);background:var(--crab-l)}
.role.taken{border-style:dashed;opacity:.75}
.role.taken:not(.mine){cursor:not-allowed}

/* 剧本 */
.script{background:linear-gradient(135deg,#fff7ed,#ffedd5);border:1.5px solid #fdba74;border-radius:var(--r);padding:16px 18px;margin-top:14px;position:relative;display:none}
.script.show{display:block;animation:pop .25s}
.script .s-title{font-size:14px;font-weight:800;color:var(--crab-d);margin-bottom:8px}
.script .s-body{font-size:13.5px;line-height:1.9;white-space:pre-wrap;color:#431407}
@keyframes pop{from{transform:translateY(6px);opacity:0}to{transform:none;opacity:1}}

/* ---------- 活动一：配对 ---------- */
.pair-wrap{display:grid;grid-template-columns:1fr 1fr;gap:16px;margin-top:14px}
.pair-col h4{font-size:13.5px;font-weight:800;padding:9px 14px;border-radius:10px;margin-bottom:10px}
.col-logistics{background:var(--crab-l);color:var(--crab-d)}
.col-data{background:var(--lake-l);color:var(--lake-d)}
.cn-row{display:flex;align-items:center;gap:10px;background:var(--lake-ll);border:1.5px dashed var(--lake);border-radius:12px;padding:10px 12px;margin-bottom:10px;min-height:56px;transition:all .12s}
.cn-row.drop{border-style:dashed}
.cn-row.hover{border-style:solid;border-color:var(--crab);background:var(--crab-l);box-shadow:0 0 0 3px rgba(234,88,12,.15)}
.cn-row.ok{border-style:solid;border-color:#86c79b;background:var(--green-l)}
.cn-row .num{width:24px;height:24px;border-radius:8px;background:var(--crab);color:#fff;display:flex;align-items:center;justify-content:center;font-size:13px;font-weight:800;flex-shrink:0}
.cn-row .txt{font-size:13.5px;line-height:1.5;flex:1}
.cn-row .slot{font-size:11.5px;color:var(--ink-2);border:1px dashed var(--line);border-radius:8px;padding:4px 9px;background:#fff;white-space:nowrap;flex-shrink:0}
.net-card{border:1.5px solid var(--line);border-radius:12px;padding:11px 13px;margin-bottom:10px;font-size:13.5px;line-height:1.6;background:#fff;cursor:grab;transition:all .12s;position:relative;display:flex;align-items:center;gap:10px}
.net-card:hover{box-shadow:0 4px 12px rgba(15,23,42,.08);border-color:var(--lake)}
.net-card.drag{opacity:.5;transform:scale(.98)}
.net-card.used{opacity:.5;pointer-events:none}
.net-card b{color:var(--lake)}
.net-card .o-num{width:22px;height:22px;border-radius:7px;background:var(--lake);color:#fff;display:flex;align-items:center;justify-content:center;font-size:12px;font-weight:800;flex-shrink:0}
.net-card .o-name{flex:1;line-height:1.5}
.net-card .grip{color:var(--ink-3);font-size:16px;flex-shrink:0}
.cn-row.ref{background:#fff;border-style:solid;border-color:var(--line);cursor:default}
.cn-row.ref .slot{display:none}
.res-card{border:1.5px solid #fcd34d;border-radius:12px;background:linear-gradient(135deg,#fffbeb,#fef3c7);padding:12px 14px;font-size:13.5px}
.res-card .r-title{font-weight:800;color:var(--amber-d);margin-bottom:4px}
.res-card .r-meta{font-size:11.5px;color:var(--ink-2);margin-bottom:6px}
.res-card .r-preview{margin-bottom:8px;text-align:center}
.res-card .r-preview img{max-width:220px;max-height:140px;border-radius:8px;border:1px solid #fde68a}
.res-card .r-content{color:var(--ink);line-height:1.7;word-break:break-all}
.ai-box{display:none;margin-top:16px;border-radius:var(--r);overflow:hidden;border:1.5px solid var(--line)}
.ai-box.show{display:block}
.ai-box .ai-head{display:flex;align-items:center;gap:10px;background:linear-gradient(135deg,#155e75,#0e7490);color:#fff;padding:10px 14px;font-size:13px;font-weight:700}
.ai-box .ai-head img{width:26px;height:26px;border-radius:50%;background:#fff}
.ai-box .ai-body{padding:16px;font-size:14px;line-height:1.9;color:var(--ink)}
.ai-box .ai-body .pairs-list{margin:8px 0;font-size:12.5px;color:var(--ink-2)}
.ai-box .ai-body .pairs-list .ok{color:var(--green)}
.ai-box .ai-body .pairs-list .bad{color:var(--red);font-weight:700}

/* ---------- 活动二 ---------- */
.fill-row{display:flex;align-items:center;gap:8px;flex-wrap:wrap;font-size:14.5px;line-height:2.2}
.fill-row input{width:56px;text-align:center;border:1.5px solid var(--line);border-radius:9px;padding:7px 6px;font-size:15px;font-weight:700;outline:none}
.fill-row input:focus{border-color:var(--lake)}
.ip-show{display:flex;align-items:center;gap:10px;background:#0f172a;color:#7dd3fc;border-radius:12px;padding:14px 16px;font-family:Consolas,Menlo,monospace;font-size:15px;flex-wrap:wrap}
.ip-show .lab{color:#94a3b8;font-size:12px;font-family:inherit}
.v6-grid{display:grid;grid-template-columns:1fr 1fr;gap:12px;margin-top:14px}
.v6-item{border:1.5px solid var(--line);border-radius:12px;padding:14px;background:var(--lake-ll)}
.v6-item b{display:block;font-size:13px;color:var(--lake-d);margin-bottom:6px}
.v6-item code{display:block;font-family:Consolas,Menlo,monospace;font-size:13px;color:var(--lake);word-break:break-all;line-height:1.8}

/* ---------- 活动三 ---------- */
.flow{display:flex;align-items:stretch;gap:8px;overflow-x:auto;padding:6px 2px 12px}
.flow .node{flex:0 0 auto;min-width:108px;background:#fff;border:1.5px solid var(--line);border-radius:12px;padding:10px 8px;text-align:center;font-size:12px;position:relative}
.flow .node .nemoji{font-size:22px}
.flow .node b{display:block;font-size:12px;margin-top:4px;line-height:1.3}
.flow .node .who{font-size:10.5px;color:var(--ink-2);margin-top:3px}
.flow .node.now{border-color:var(--crab);background:var(--crab-l);box-shadow:0 0 0 3px rgba(234,88,12,.12)}
.flow .node.done{border-color:#86c79b;background:var(--green-l)}
.flow .node.rout{background:var(--amber-l)}
.flow .arr{flex:0 0 auto;display:flex;align-items:center;color:var(--ink-2);font-size:16px;padding:0 2px}
.pkt{display:flex;gap:8px;flex-wrap:wrap;margin-top:10px}
.pkt .p{flex:1 1 150px;border:1.5px solid var(--line);border-radius:10px;padding:9px 11px;font-size:12px;background:#fff}
.pkt .p .pn{font-weight:800;color:var(--crab-d)}
.pkt .p div{margin-top:3px;color:var(--ink-2);line-height:1.5}
.pkt .p div b{color:var(--ink)}
.send-wait{display:none;text-align:center;padding:22px;color:var(--ink-2);font-size:13.5px}
.send-wait.show{display:block}
.timeline{margin-top:14px;border-left:3px solid var(--lake);margin-left:8px;padding-left:18px}
.timeline .tl{position:relative;padding:8px 0 14px;font-size:13px;color:var(--ink-2);line-height:1.7}
.timeline .tl::before{content:"";position:absolute;left:-24px;top:13px;width:11px;height:11px;border-radius:50%;background:var(--crab);border:2px solid #fff;box-shadow:0 0 0 2px var(--crab-l)}
.timeline .tl b{color:var(--ink)}
.timeline .tl.ok{color:var(--green);font-weight:600}
.timeline .tl.ok::before{background:var(--green)}

/* ---------- 评价 ---------- */
.star{font-size:26px;cursor:pointer;color:#e2e8f0;transition:transform .1s}
.star.on{color:#f59e0b}
.star:hover{transform:scale(1.15)}
.star-row{display:flex;gap:6px;margin-top:6px}
textarea{width:100%;border:1.5px solid var(--line);border-radius:10px;padding:10px 12px;font-size:13.5px;font-family:inherit;resize:vertical;min-height:80px;outline:none}
textarea:focus{border-color:var(--lake)}
.form-item{margin-bottom:14px}
.form-item label{display:block;font-size:13.5px;font-weight:700;margin-bottom:6px}

/* ---------- 小满同学悬浮窗 ---------- */
#xm-fab{position:fixed;left:18px;bottom:18px;width:62px;height:62px;border-radius:50%;border:none;cursor:pointer;padding:0;background:#fff;box-shadow:0 6px 22px rgba(15,23,42,.25);z-index:1000;overflow:hidden;transition:transform .15s}
#xm-fab:hover{transform:scale(1.08)}
#xm-fab img{width:100%;height:100%;object-fit:cover}
#xm-fab .tip{position:absolute;top:-4px;right:-4px;background:var(--crab);color:#fff;font-size:10px;width:18px;height:18px;border-radius:50%;display:flex;align-items:center;justify-content:center;font-weight:800}
#xm-panel{position:fixed;left:18px;bottom:88px;width:330px;max-width:calc(100vw - 36px);height:460px;max-height:calc(100vh - 130px);background:#fff;border-radius:18px;box-shadow:0 12px 40px rgba(15,23,42,.28);z-index:1001;display:none;flex-direction:column;overflow:hidden;border:1px solid var(--line)}
#xm-panel.open{display:flex;animation:slideUp .2s}
@keyframes slideUp{from{transform:translateY(14px);opacity:0}to{transform:none;opacity:1}}
#xm-panel .xm-head{display:flex;align-items:center;gap:10px;padding:12px 14px;background:linear-gradient(135deg,#155e75,#0e7490);color:#fff}
#xm-panel .xm-head img{width:36px;height:36px;border-radius:50%;background:#fff;object-fit:cover}
#xm-panel .xm-head b{font-size:14px}
#xm-panel .xm-head span{font-size:11px;opacity:.85;display:block}
#xm-panel .xm-close{margin-left:auto;background:rgba(255,255,255,.18);border:none;color:#fff;width:26px;height:26px;border-radius:8px;cursor:pointer;font-size:14px}
#xm-msgs{flex:1;overflow-y:auto;padding:14px;background:#f4f7f8}
.xm-msg{display:flex;gap:8px;margin-bottom:12px}
.xm-msg .av{width:30px;height:30px;border-radius:50%;overflow:hidden;flex-shrink:0;background:#fff;box-shadow:0 0 0 1px var(--line)}
.xm-msg .av img{width:100%;height:100%;object-fit:cover}
.xm-msg .bub{background:#fff;border:1px solid var(--line);border-radius:12px;border-top-left-radius:3px;padding:9px 12px;font-size:13px;line-height:1.75;max-width:78%;white-space:pre-wrap}
.xm-msg.me{flex-direction:row-reverse}
.xm-msg.me .bub{background:var(--lake);color:#fff;border:none;border-radius:12px;border-top-right-radius:3px}
#xm-input-row{display:flex;gap:8px;padding:10px;border-top:1px solid var(--line);background:#fff}
#xm-input{flex:1;border:1.5px solid var(--line);border-radius:10px;padding:9px 12px;font-size:13px;outline:none}
#xm-input:focus{border-color:var(--lake)}
#xm-send{flex-shrink:0}
.xm-typing{display:inline-block;color:var(--ink-2);font-size:12px}

/* ---------- 教师面板 ---------- */
.t-panel{display:none;border:1.5px solid #c4b5fd;background:linear-gradient(135deg,#faf5ff,#f5f3ff);border-radius:var(--r);padding:16px 18px;margin-bottom:16px}
.t-panel.show{display:block}
.t-panel h4{font-size:14px;font-weight:800;color:var(--purple);margin-bottom:10px;display:flex;align-items:center;gap:8px}
.t-panel .t-btns{display:flex;gap:10px;flex-wrap:wrap}
.t-panel p{font-size:12.5px;color:var(--ink-2);margin-top:8px;line-height:1.6}

/* ---------- 首页 hero ---------- */
.hero{background:linear-gradient(135deg,#0c4a6e 0%,#0e7490 55%,#06b6d4 100%);border-radius:20px;color:#fff;padding:30px 28px;position:relative;overflow:hidden;margin-bottom:18px;box-shadow:0 10px 30px rgba(14,116,144,.3)}
.hero::after{content:"🦀";position:absolute;right:-10px;bottom:-30px;font-size:150px;opacity:.14;transform:rotate(-15deg)}
.hero .h-tag{display:inline-block;background:rgba(255,255,255,.16);border:1px solid rgba(255,255,255,.35);padding:3px 12px;border-radius:99px;font-size:12px;margin-bottom:12px}
.hero h2{font-size:26px;font-weight:800;margin-bottom:10px}
.hero p{font-size:14px;line-height:1.9;opacity:.95;max-width:680px}
.hero .hl{color:#fde68a;font-weight:800}
.sec-cards{display:grid;grid-template-columns:repeat(5,1fr);gap:12px;margin-bottom:18px}
.sec-card{text-decoration:none;color:inherit;background:var(--card);border:1.5px solid var(--line);border-radius:var(--r);padding:16px 14px;text-align:center;transition:all .15s;position:relative}
.sec-card:hover{transform:translateY(-3px);box-shadow:0 8px 20px rgba(15,23,42,.1);border-color:var(--lake)}
.sec-card .ic{font-size:30px;margin-bottom:6px}
.sec-card b{display:block;font-size:13.5px;margin-bottom:4px}
.sec-card span{font-size:11.5px;color:var(--ink-2);line-height:1.5;display:block}
.sec-card.done::after{content:"✓";position:absolute;top:8px;right:10px;color:var(--green);font-weight:800}
.overview{display:grid;grid-template-columns:1fr 1fr;gap:16px}
.ov-item{background:var(--lake-ll);border:1px solid var(--line);border-radius:12px;padding:14px 16px}
.ov-item b{display:block;font-size:13.5px;color:var(--lake-d);margin-bottom:6px}
.ov-item p{font-size:13px;color:var(--ink-2);line-height:1.8}

/* ---------- 响应式 ---------- */
@media(max-width:760px){
  .userbar{margin-left:0;width:100%}
  .roles{grid-template-columns:repeat(2,1fr)}
  .pair-wrap{grid-template-columns:1fr}
  .sec-cards{grid-template-columns:repeat(2,1fr)}
  .overview{grid-template-columns:1fr}
  .v6-grid{grid-template-columns:1fr}
  /* 窄屏：导航不再隐藏，改为横向滑动 */
  .topbar .nav{flex-wrap:nowrap;overflow-x:auto;padding-bottom:4px;-webkit-overflow-scrolling:touch}
  .topbar .nav a{flex:0 0 auto;min-width:100px}
  .topbar .nav::-webkit-scrollbar{height:5px}
  .topbar .nav::-webkit-scrollbar-thumb{background:var(--line);border-radius:99px}
}
@media(max-width:480px){
  .roles{grid-template-columns:1fr}
}

/* ---------- 加入协作组弹窗 ---------- */
.join-mask{position:fixed;inset:0;background:rgba(15,23,42,.45);display:none;align-items:center;justify-content:center;z-index:2000;padding:20px}
.join-mask.open{display:flex}
.join-card{background:var(--card);border:1px solid var(--line);border-radius:18px;padding:22px 24px;max-width:420px;width:100%;box-shadow:0 18px 50px rgba(15,23,42,.3);text-align:center;animation:pop .2s}
.join-h{font-size:18px;font-weight:800;color:var(--lake-d)}
.join-sub{font-size:13.5px;color:var(--ink-2);margin-top:8px;line-height:1.75}
.join-row{display:flex;gap:8px;margin-top:14px;justify-content:center;flex-wrap:wrap}
.join-row .in-group{flex:1;min-width:130px;width:auto;font-size:16px;font-weight:700;letter-spacing:3px;text-align:center;border:1.5px solid var(--line);border-radius:10px;padding:9px 10px;outline:none;background:#fff}
.join-row .in-group:focus{border-color:var(--lake)}
.join-note{font-size:12.5px;color:var(--ink-2);margin-top:14px;line-height:1.75;background:var(--lake-ll);border-radius:12px;padding:10px 12px;text-align:left}
.join-later{margin-top:12px;background:none;border:none;color:var(--ink-2);font-size:12.5px;cursor:pointer;text-decoration:underline}
.join-later:hover{color:var(--lake)}

/* ---------- 第四轮新增：入组后状态 + 退出按钮 ---------- */
.ub-in{display:flex;align-items:center;gap:8px;flex-wrap:wrap}
.ub-who{font-size:13px;font-weight:800;color:var(--lake-d);white-space:nowrap}
.ub-members{display:flex;align-items:center;gap:6px;flex-wrap:wrap}
.ub-chip{background:var(--lake-ll);border:1.5px solid var(--line);border-radius:99px;padding:3px 10px;font-size:12px;font-weight:600;color:var(--lake-d);white-space:nowrap}
.ub-chip.me{background:var(--crab);border-color:var(--crab-d);color:#fff;font-weight:800;box-shadow:0 2px 8px rgba(234,88,12,.35)}
.ub-chip.me .me-tag{font-style:normal;font-size:11px;font-weight:800;margin-left:5px;padding:1px 6px;border-radius:99px;background:#fff;color:var(--crab-d);display:inline-block;line-height:1.35}
.userbar .btn-line{border-color:var(--red);color:var(--red)}
.userbar .btn-line:hover{background:var(--red-l)}
/* 课堂锁定：锁定期间导航不可切换 */
.nav.nav-locked a:not(.cur){opacity:.4;cursor:not-allowed}
.nav-lock{margin-left:12px;font-size:12px;font-weight:800;color:var(--crab-d);background:var(--crab-l);border:1.5px solid var(--crab);border-radius:99px;padding:2px 10px;white-space:nowrap}

/* ---------- 第四轮新增：活动1 拖拽配对 ---------- */
.tray{display:flex;flex-wrap:wrap;gap:10px;padding:14px;border:2px dashed var(--line);border-radius:14px;background:#fff;transition:border-color .12s}
.tray.hover{border-color:var(--crab);background:var(--crab-l)}
.dt-tag{display:inline-block;border:1.5px solid var(--lake);background:var(--lake-l);color:var(--lake-d);border-radius:10px;padding:9px 14px;font-size:13.5px;font-weight:800;cursor:grab;user-select:none;transition:all .12s}
.dt-tag:hover{transform:translateY(-2px);box-shadow:0 4px 10px rgba(14,116,144,.18)}
.dt-tag.drag{opacity:.4}
.tray-empty{font-size:12.5px;color:var(--ink-2);background:var(--lake-ll);border-radius:10px;padding:12px}
.cn-row .slot.filled{border-style:solid;border-color:var(--crab);background:var(--crab-l)}
.sl-tag{display:inline-block;background:var(--crab);color:#fff;border-radius:7px;padding:3px 9px;font-size:12px;font-weight:800;cursor:grab;user-select:none}
.sl-tag.drag{opacity:.4}
.pair-ok{display:inline-block;margin-left:10px;background:var(--green-l);color:var(--green);font-size:12.5px;font-weight:800;padding:3px 12px;border-radius:99px}
/* 教师端：小节标题 / 说明 / 配对进度小标签 / IP 展示墙 / 进度条 */
.sub-h{margin:14px 0 4px;font-size:13.5px;font-weight:800;color:var(--ink)}
.sub-tip{margin-bottom:8px;font-size:12.5px;color:var(--ink-2);line-height:1.7}
.pair-chips{margin-top:6px;display:flex;flex-wrap:wrap;gap:6px}
.pair-chip{font-size:11.5px;font-weight:700;background:#f1f5f9;color:var(--ink-2);border:1px solid var(--line);border-radius:99px;padding:2px 9px}
.pair-chip.ok{background:var(--green-l);color:var(--green);border-color:#86c79b}
.ip-wall{display:flex;flex-wrap:wrap;gap:10px;margin-top:6px}
.ip-card{min-width:150px;flex:0 1 auto;background:#fff;border:1px solid var(--line);border-radius:12px;padding:9px 14px;box-shadow:0 2px 8px rgba(14,116,144,.06)}
.ip-card .ipv4{font-family:Consolas,Monaco,monospace;font-size:15px;font-weight:800;color:var(--lake-d)}
.ip-card .ip-owner{margin-top:3px;font-size:11.5px;color:var(--ink-2)}
.pbar{display:inline-block;vertical-align:middle;width:90px;height:7px;background:#e2edf1;border-radius:99px;overflow:hidden}
.pbar i{display:block;height:100%;background:var(--crab);border-radius:99px;transition:width .25s}
/* 学生端：同伴对我的评价 */
.got-peer{border:1px solid var(--line);border-radius:12px;padding:10px 14px;margin-bottom:10px;background:#fff}
.got-peer:last-child{margin-bottom:0}
.got-name{font-size:13.5px;font-weight:800;color:var(--ink);margin-bottom:6px}
.got-avg{margin-left:10px;font-size:12px;font-weight:700;color:var(--crab-d)}
.got-rows{display:flex;flex-wrap:wrap;gap:10px 18px}
.got-row{display:flex;align-items:center;gap:5px;font-size:13px}
.got-k{color:var(--ink-2);font-weight:700}
.got-star{color:var(--crab);letter-spacing:1px}
.got-star i{color:#d7dee4;font-style:normal}
/* 预先配好并锁定的两对：不可拖动、样式与可拖动的区分开 */
.cn-row.locked{background:#f1fbf4;border-style:solid;border-color:#9ed4ac;cursor:default}
.cn-row.locked .num{background:#2e9e5b}
.cn-row.locked .slot.filled{border-color:#9ed4ac;background:#e6f7ec}
.cn-row.locked .sl-tag{cursor:default;background:#2e9e5b}

/* ---------- 第四轮新增：活动3 ---------- */
.sub-title{font-size:15px;font-weight:800;color:var(--lake-d)}
.img-pool{display:flex;gap:12px;flex-wrap:wrap;justify-content:center;margin-top:8px}
.img-card{width:160px;border:1.5px solid var(--line);border-radius:12px;padding:10px;background:#fff;cursor:pointer;text-align:center;transition:all .15s}
.img-card:hover{transform:translateY(-3px);border-color:var(--crab);box-shadow:0 6px 16px rgba(234,88,12,.16)}
.img-card canvas{width:138px;height:138px;border-radius:8px;background:var(--lake-ll)}
.img-name{font-size:12px;font-weight:700;margin-top:8px;line-height:1.4;color:var(--ink)}
.preview-img{display:inline-block;margin-top:10px}
.preview-img canvas{width:220px;height:220px;border-radius:12px;border:1.5px solid var(--line);background:#fff}
.grid3x3{display:grid;grid-template-columns:repeat(3,110px);gap:6px;justify-content:center}
.grid3x3 .cell{width:110px;height:110px;border:1.5px dashed var(--line);border-radius:10px;background:#fff;overflow:hidden;display:flex;align-items:center;justify-content:center;font-size:13px;color:var(--ink-2)}
.grid3x3 .cell canvas{width:100%;height:100%;display:block}
.grid3x3 .cell.slot{font-weight:800;font-size:15px;color:#94a3b8;cursor:pointer;transition:all .12s}
.grid3x3 .cell.slot:hover{border-color:var(--crab)}
.grid3x3 .cell.slot.filled{border-style:solid;border-color:#86c79b;background:var(--green-l);cursor:default}
.grid3x3 .cell.lock{border-style:solid;border-color:var(--line);background:var(--lake-ll)}
.ip-group{background:var(--lake-ll);border:1px solid var(--line);border-radius:12px;padding:12px 14px;margin-top:10px}
.ip-group b{font-size:13.5px;color:var(--lake-d)}
.ip-opts{display:flex;gap:8px;flex-wrap:wrap;margin-top:8px}
.ip-opt{display:flex;align-items:center;gap:6px;border:1.5px solid var(--line);border-radius:9px;padding:7px 12px;background:#fff;font-size:13px;cursor:pointer}
.ip-opt:has(input:checked){border-color:var(--crab);background:var(--crab-l)}
.ip-opt code{font-family:Consolas,Menlo,monospace;font-weight:700;color:var(--lake)}
.ip-opt.off{opacity:.55;cursor:not-allowed}
.anim-svg{width:100%;max-width:680px;display:block;margin:0 auto;background:#f2fafc;border:1px solid var(--line);border-radius:14px}
.asm-area{display:grid;grid-template-columns:auto 1fr;gap:20px;align-items:start;margin-top:12px}
.asm-tray{display:flex;flex-wrap:wrap;gap:8px}
.asm-tile{width:96px;height:96px;border:1.5px solid var(--line);border-radius:10px;overflow:hidden;cursor:grab;background:#fff;box-shadow:0 2px 6px rgba(15,23,42,.06);transition:all .12s}
.asm-tile:hover{border-color:var(--lake)}
.asm-tile.sel{border-color:var(--crab);box-shadow:0 0 0 3px rgba(234,88,12,.2)}
.asm-tile canvas{width:100%;height:100%;display:block}
.asm-tray-wrap{visibility:visible}
.done-row{display:flex;gap:20px;align-items:flex-start;margin-top:12px;flex-wrap:wrap}
.done-row canvas{width:300px;height:300px;border-radius:12px;border:2px solid #86c79b;background:#fff}
.done-info{font-size:13px;line-height:2.1}
.done-line b{color:var(--crab-d)}

/* ---------- 第四轮新增：素养综合测评（五维雷达） ---------- */
.eval-row{display:grid;grid-template-columns:300px 1fr;gap:22px;align-items:center}
.radar{width:100%;max-width:300px;margin:0 auto}
.radar-title{text-align:center;font-size:13px;font-weight:800;color:var(--ink-2);margin-bottom:4px}
.chip-title{font-size:13.5px;font-weight:800;margin-bottom:10px;color:var(--ink)}
.chip{display:flex;align-items:center;gap:8px;background:var(--lake-ll);border:1px solid var(--line);border-radius:10px;padding:9px 13px;margin-bottom:8px;font-size:13px}
.chip b{color:var(--lake-d)}
.chip span{margin-left:auto;font-weight:800;color:var(--crab-d)}
.chip i{font-style:normal;font-size:11px;background:var(--amber-l);color:#92400e;padding:1px 8px;border-radius:99px}
.chip.full{background:var(--crab-l);border-color:#fdba74}

@media(max-width:760px){
  .asm-area{grid-template-columns:1fr}
  .eval-row{grid-template-columns:1fr}
}