/* ═══════════════════════════════════════════════════
   云课堂 · 实时互动白板  样式
   ═══════════════════════════════════════════════════ */

:root{
  --bg:#eef1f7;
  --panel:#ffffff;
  --panel-2:#f7f9fc;
  --line:#e3e8f0;
  --line-2:#eef1f6;
  --text:#0f172a;
  --text-2:#475467;
  --muted:#8a94a6;
  --brand:#2f6fed;
  --brand-2:#5b8cff;
  --brand-soft:#eef4ff;
  --violet:#7c5cff;
  --green:#12b76a;
  --amber:#f79009;
  --red:#f04438;
  --radius:12px;
  --radius-lg:18px;
  --shadow-sm:0 1px 2px rgba(16,24,40,.06), 0 1px 3px rgba(16,24,40,.05);
  --shadow:0 6px 20px rgba(16,24,40,.08), 0 2px 6px rgba(16,24,40,.04);
  --shadow-lg:0 24px 60px rgba(16,24,40,.18), 0 8px 22px rgba(16,24,40,.08);
  --mono:ui-monospace,SFMono-Regular,"SF Mono",Menlo,Consolas,monospace;
}

*{box-sizing:border-box;-webkit-tap-highlight-color:transparent}
html,body{height:100%;margin:0}
body{
  font-family:-apple-system,BlinkMacSystemFont,"Segoe UI","PingFang SC","Hiragino Sans GB","Microsoft YaHei",sans-serif;
  background:var(--bg); color:var(--text);
  font-size:14px; line-height:1.55;
  overflow:hidden;
  -webkit-font-smoothing:antialiased;
}
button,input,textarea{font-family:inherit;font-size:inherit;color:inherit}
button{cursor:pointer;border:0;background:none}
.hidden{display:none !important}

/* ───────────── 通用按钮 ───────────── */
.btn{
  display:inline-flex;align-items:center;justify-content:center;gap:6px;
  height:36px;padding:0 14px;border-radius:9px;
  font-size:13.5px;font-weight:600;white-space:nowrap;
  transition:.16s ease;
  background:var(--panel);border:1px solid var(--line);
}
.btn:hover{background:var(--panel-2);border-color:#d3daea}
.btn:active{transform:translateY(1px)}
.btn-primary{background:linear-gradient(180deg,var(--brand-2),var(--brand));color:#fff;border-color:transparent;box-shadow:0 2px 8px rgba(47,111,237,.28)}
.btn-primary:hover{filter:brightness(1.05);background:linear-gradient(180deg,var(--brand-2),var(--brand))}
.btn-ghost{background:rgba(255,255,255,.7)}
.btn-lg{height:46px;font-size:15px;border-radius:11px}
.btn-block{width:100%}
.btn-ico{width:36px;padding:0}

/* ═══════════════ 入口页 ═══════════════ */
.gate{
  position:fixed;inset:0;z-index:100;
  display:flex;flex-direction:column;align-items:center;justify-content:center;
  gap:26px;padding:24px;overflow:auto;
}
.gate-bg{
  position:absolute;inset:0;z-index:-1;
  background:
    radial-gradient(900px 520px at 12% -8%, #dbe7ff 0%, transparent 62%),
    radial-gradient(760px 460px at 92% 8%, #e8e2ff 0%, transparent 60%),
    radial-gradient(700px 500px at 50% 112%, #d9f2e8 0%, transparent 62%),
    linear-gradient(180deg,#f6f8fd,#eef1f7);
}
.gate-bg::after{
  content:"";position:absolute;inset:0;
  background-image:linear-gradient(rgba(15,23,42,.035) 1px,transparent 1px),
                   linear-gradient(90deg,rgba(15,23,42,.035) 1px,transparent 1px);
  background-size:34px 34px;
  mask-image:radial-gradient(720px 480px at 50% 40%,#000 30%,transparent 78%);
}
.gate-card{
  width:min(430px,100%);background:rgba(255,255,255,.9);backdrop-filter:blur(18px);
  border:1px solid rgba(255,255,255,.9);border-radius:22px;padding:28px 28px 24px;
  box-shadow:var(--shadow-lg);
  animation:gateIn .5s cubic-bezier(.2,.8,.3,1) both;
}
@keyframes gateIn{from{opacity:0;transform:translateY(16px) scale(.985)}to{opacity:1;transform:none}}
.gate-head{text-align:center;margin-bottom:20px}
.logo{display:flex;justify-content:center;margin-bottom:10px;filter:drop-shadow(0 6px 14px rgba(47,111,237,.28))}
.gate-head h1{margin:0;font-size:25px;letter-spacing:.5px;font-weight:800}
.gate-sub{margin:4px 0 0;color:var(--muted);font-size:13px}

.gate-tabs{display:flex;background:var(--panel-2);border:1px solid var(--line);border-radius:11px;padding:3px;margin-bottom:18px}
.gtab{flex:1;height:34px;border-radius:8px;font-size:13.5px;font-weight:600;color:var(--text-2);transition:.16s}
.gtab.active{background:#fff;color:var(--brand);box-shadow:var(--shadow-sm)}
.gpane{display:none;animation:fadeIn .22s ease both}
.gpane.active{display:block}
@keyframes fadeIn{from{opacity:0;transform:translateY(4px)}to{opacity:1;transform:none}}

.field{display:block;margin-bottom:14px}
.field>span{display:block;font-size:12.5px;font-weight:600;color:var(--text-2);margin-bottom:6px}
.field input,.field select{
  width:100%;height:44px;padding:0 13px;border-radius:10px;
  border:1px solid var(--line);background:#fff;outline:none;transition:.16s;
}
.field select{cursor:pointer;font-size:13.5px;color:var(--text)}
.field input:focus,.field select:focus{border-color:var(--brand);box-shadow:0 0 0 3.5px rgba(47,111,237,.14)}
.code-input{font-family:var(--mono);font-size:20px;letter-spacing:7px;text-align:center;text-transform:uppercase;font-weight:700}
.gate-hint{margin:12px 0 0;font-size:12px;color:var(--muted);text-align:center;line-height:1.6}
.gate-msg{margin-top:14px;font-size:13px;text-align:center;color:var(--red);min-height:18px}

.teacher-banner{
  display:flex;align-items:center;justify-content:space-between;gap:12px;
  background:linear-gradient(135deg,#fff6e0,#ffefcc);border:1px solid #ffdfae;
  border-radius:12px;padding:11px 13px;margin-bottom:16px;
}
.teacher-banner .tb-txt{min-width:0}
.teacher-banner b{display:block;font-size:13px;color:#8a4b00}
.teacher-banner span{font-size:11.5px;color:#a9702f;font-family:var(--mono);letter-spacing:.5px}
.teacher-banner .btn{height:32px;padding:0 12px;font-size:12.5px;flex:0 0 auto}

.gate-feats{display:grid;grid-template-columns:repeat(4,1fr);gap:12px;width:min(720px,100%)}
@media(max-width:720px){.gate-feats{grid-template-columns:repeat(2,1fr)}}
.feat{
  background:rgba(255,255,255,.72);backdrop-filter:blur(10px);
  border:1px solid rgba(255,255,255,.9);border-radius:14px;padding:13px 14px;
  box-shadow:var(--shadow-sm);
}
.feat b{display:block;font-size:13.5px;margin-bottom:2px}
.feat span{font-size:11.5px;color:var(--muted)}

/* ═══════════════ 课堂布局 ═══════════════ */
.classroom{position:fixed;inset:0;display:flex;flex-direction:column}
.topbar{
  height:56px;flex:0 0 56px;display:flex;align-items:center;justify-content:space-between;
  padding:0 14px;background:var(--panel);border-bottom:1px solid var(--line);z-index:20;
}
.tb-left{display:flex;align-items:center;gap:12px;min-width:0}
.brand-mini{flex:0 0 auto}
.room-title{min-width:0}
.rt-name{font-weight:700;font-size:14.5px;white-space:nowrap;overflow:hidden;text-overflow:ellipsis;max-width:38vw}
.rt-sub{display:flex;align-items:center;gap:6px;font-size:11.5px;color:var(--muted);margin-top:1px}
.chip{display:inline-flex;align-items:center;gap:4px;height:19px;padding:0 8px;border-radius:999px;font-size:11px}
.chip-code{background:var(--brand-soft);color:var(--brand);font-weight:600;border:1px solid #d7e3ff}
.chip-code b{font-family:var(--mono);letter-spacing:1px}
.chip-code:hover{background:#e2ecff}
.dot-live{width:7px;height:7px;border-radius:50%;background:var(--green);box-shadow:0 0 0 3px rgba(18,183,106,.16);animation:pulse 2s infinite}
.dot-live.off{background:var(--muted);box-shadow:0 0 0 3px rgba(138,148,166,.16);animation:none}
@keyframes pulse{0%,100%{opacity:1}50%{opacity:.42}}
.sep{opacity:.5}
.tb-right{display:flex;align-items:center;gap:9px}
.role-badge{
  height:26px;padding:0 11px;border-radius:999px;display:inline-flex;align-items:center;
  font-size:12px;font-weight:700;background:#eef1f6;color:var(--text-2);
}
.role-badge.teacher{background:linear-gradient(135deg,#fff2d6,#ffe6b8);color:#a05a00}

.workspace{flex:1;display:flex;min-height:0;position:relative}

/* ───────────── 左工具栏 ───────────── */
.toolbar{
  width:70px;flex:0 0 70px;background:var(--panel);border-right:1px solid var(--line);
  display:flex;flex-direction:column;align-items:center;gap:6px;padding:10px 0;
  overflow-y:auto;overflow-x:hidden;z-index:15;
}
.toolbar::-webkit-scrollbar{width:0}

/* ── 工具栏把手 / 图钉 ── */
.tb-grip{
  width:42px;height:16px;border-radius:8px;flex:0 0 16px;cursor:grab;
  display:flex;align-items:center;justify-content:center;
  color:var(--muted);font-size:13px;line-height:1;user-select:none;
  background:rgba(15,23,42,.06);letter-spacing:-1px;
}
.tb-grip:hover{background:rgba(15,23,42,.12);color:var(--text-2)}
.tb-grip:active{cursor:grabbing}
.tb-pin{
  width:26px;height:26px;border-radius:8px;border:1px solid var(--line);
  background:var(--panel);color:var(--muted);cursor:pointer;padding:0;
  display:flex;align-items:center;justify-content:center;flex:0 0 26px;
}
.tb-pin:hover{color:var(--text-2);background:var(--brand-soft)}
.tb-pin.active{color:#fff;background:var(--brand);border-color:var(--brand);transform:rotate(35deg)}

/* 工具栏拖出后：脱离文档流，跟随鼠标位置（位置由 JS 写进 style） */
.toolbar.floating{
  position:fixed;z-index:60;width:70px;border-right:1px solid var(--line);
  border-radius:12px;box-shadow:var(--shadow);max-height:calc(100vh - 20px);
}

/* ── 全屏播放：四边 UI 改为「贴边抽屉」 ──
   topbar=上、toolbar=左、sidebar=右、dock=下（HTML 里 data-drawer 标记）。
   抽屉平时滑出屏幕外（.fs-out），鼠标贴到对应边时由 JS 移除该类滑回来。 */
body.fs-mode .topbar,
body.fs-mode .toolbar:not(.floating),
body.fs-mode .sidebar{
  position:absolute;z-index:40;
}
body.fs-mode .topbar{top:0;left:0;right:0}
body.fs-mode .toolbar:not(.floating){top:0;left:0;bottom:0}
body.fs-mode .sidebar{top:0;right:0;bottom:0}
body.fs-mode [data-drawer]{transition:transform .24s ease}
body.fs-mode [data-drawer].fs-out{pointer-events:none}
body.fs-mode [data-drawer="top"].fs-out{transform:translateY(-100%)}
body.fs-mode [data-drawer="left"].fs-out{transform:translateX(-100%)}
body.fs-mode [data-drawer="right"].fs-out{transform:translateX(100%)}
body.fs-mode [data-drawer="bottom"].fs-out{transform:translateX(-50%) translateY(calc(100% + 20px))}

/* 全屏时的「菜单」按钮：平时不显示，进全屏才出现（右下角，44px 够手指点） */
#fsHandle{
  display:none;position:fixed;right:14px;bottom:14px;z-index:55;
  width:44px;height:44px;border-radius:50%;padding:0;
  border:1px solid var(--line);background:rgba(255,255,255,.92);
  backdrop-filter:blur(8px);box-shadow:var(--shadow);
  color:var(--text-2);cursor:pointer;
  align-items:center;justify-content:center;
}
body.fs-mode #fsHandle{display:flex}
#fsHandle:hover{color:var(--text-1);background:#fff}
#fsHandle:active{transform:scale(.93)}
#fsHandle.open{background:var(--brand);border-color:var(--brand);color:#fff}
.tool-group{display:flex;flex-direction:column;gap:5px;align-items:center}
.tool-group.colors{flex-direction:row;flex-wrap:wrap;width:58px;justify-content:center;gap:7px}
.tool-group.sizes{flex-direction:row;flex-wrap:wrap;width:56px;justify-content:center;gap:5px;margin-top:6px}
.tool-sep{width:34px;height:1px;background:var(--line);margin:4px 0}
.tool{
  width:52px;height:50px;border-radius:11px;display:flex;flex-direction:column;
  align-items:center;justify-content:center;gap:1px;color:var(--text-2);transition:.15s;
}
.tool .ico{font-size:17px;line-height:1;font-style:normal}
.tool em{font-size:10px;font-style:normal;letter-spacing:.2px}
.tool:hover{background:var(--panel-2);color:var(--text)}
.tool.active{background:var(--brand-soft);color:var(--brand);box-shadow:inset 0 0 0 1px #d7e3ff}
.tool.hand.active{background:#fff4e5;color:#b25e00;box-shadow:inset 0 0 0 1px #ffdfae}
.tool:disabled{opacity:.35;cursor:not-allowed}
.swatch{width:17px;height:17px;border-radius:50%;background:var(--c);border:2px solid #fff;box-shadow:0 0 0 1.5px var(--line);transition:.15s}
.swatch:hover{transform:scale(1.14)}
.swatch.active{box-shadow:0 0 0 2.5px var(--brand);transform:scale(1.14)}
.size{width:24px;height:24px;border-radius:7px;display:grid;place-items:center;transition:.15s;
  background:var(--panel-2);box-shadow:inset 0 0 0 1px var(--line)}
.size i{display:block;width:14px;border-radius:99px;background:var(--text-2)}
.size:hover{background:#eef1f7}
.size.active{background:var(--brand-soft);box-shadow:inset 0 0 0 1px #cfdfff}
.size.active i{background:var(--brand)}

/* ───────────── 舞台 ───────────── */
.stage{flex:1;position:relative;min-width:0;overflow:hidden;background:#e9edf4;touch-action:none}
.stage::before{
  content:"";position:absolute;inset:0;pointer-events:none;
  background-image:radial-gradient(rgba(15,23,42,.07) 1px,transparent 1px);
  background-size:22px 22px;opacity:.5;
}
.doc-scroll{position:absolute;inset:0;overflow:hidden}
.doc-layer{
  position:absolute;top:0;left:0;transform-origin:0 0;
  will-change:transform;pointer-events:none;
  background:#fff;box-shadow:0 10px 40px rgba(16,24,40,.16);
  border-radius:3px;
}
.doc-layer:empty{background:transparent;box-shadow:none}
.doc-layer > *{display:block;width:100%;height:auto}

#ink{position:absolute;inset:0;width:100%;height:100%;touch-action:none;cursor:crosshair}
/* 工具光标：画笔=钢笔、荧光笔=马克笔、橡皮=橡皮块、激光笔=红点
   约定（踩过的坑）：SVG data URI 里 # 要写成 %23、**空格也要写成 %20**，
   否则浏览器解不出图、又会静默退回十字；末尾保留 crosshair 兜底。热点是笔尖/接触点。 */
#ink[data-tool="pen"]{cursor:url("data:image/svg+xml,%3Csvg%20xmlns='http://www.w3.org/2000/svg'%20width='24'%20height='24'%20viewBox='0%200%2024%2024'%3E%3Cg%20transform='rotate(45%2012%2012)'%3E%3Crect%20x='10'%20y='5'%20width='4'%20height='13'%20rx='1'%20fill='%23111827'%20stroke='%23fff'%20stroke-width='1'/%3E%3Cpath%20d='M10%2018h4l-2%204z'%20fill='%232563eb'%20stroke='%23fff'%20stroke-width='0.8'/%3E%3C/g%3E%3C/svg%3E") 5 19, crosshair}
#ink[data-tool="marker"]{cursor:url("data:image/svg+xml,%3Csvg%20xmlns='http://www.w3.org/2000/svg'%20width='24'%20height='24'%20viewBox='0%200%2024%2024'%3E%3Cg%20transform='rotate(45%2012%2012)'%3E%3Crect%20x='9'%20y='4'%20width='6'%20height='13'%20rx='1'%20fill='%237c3aed'%20stroke='%23fff'%20stroke-width='1'/%3E%3Crect%20x='9'%20y='17'%20width='6'%20height='5'%20rx='1'%20fill='%23fbbf24'%20stroke='%23fff'%20stroke-width='0.8'/%3E%3C/g%3E%3C/svg%3E") 5 19, crosshair}
/* 橡皮：斜放的两色橡皮块（上粉下白），热点 (10,17) 是下沿接触点 */
#ink[data-tool="eraser"]{cursor:url("data:image/svg+xml,%3Csvg%20xmlns='http://www.w3.org/2000/svg'%20width='24'%20height='24'%20viewBox='0%200%2024%2024'%3E%3Cg%20transform='rotate(-35%2012%2012)'%3E%3Crect%20x='7'%20y='5'%20width='10'%20height='5'%20rx='1'%20fill='%23fb7185'%20stroke='%23111827'%20stroke-width='1'/%3E%3Crect%20x='7'%20y='10'%20width='10'%20height='5'%20rx='1'%20fill='%23fff'%20stroke='%23111827'%20stroke-width='1'/%3E%3C/g%3E%3C/svg%3E") 10 17, crosshair}
/* 激光笔：红点 + 光晕 + 白芯，热点 (10,10) 正中圆心 */
#ink[data-tool="laser"]{cursor:url("data:image/svg+xml,%3Csvg%20xmlns='http://www.w3.org/2000/svg'%20width='20'%20height='20'%20viewBox='0%200%2020%2020'%3E%3Ccircle%20cx='10'%20cy='10'%20r='8'%20fill='%23ef4444'%20fill-opacity='.22'/%3E%3Ccircle%20cx='10'%20cy='10'%20r='4'%20fill='%23ef4444'/%3E%3Ccircle%20cx='10'%20cy='10'%20r='1.5'%20fill='%23fff'/%3E%3C/svg%3E") 10 10, crosshair}
#ink.pan{cursor:grab}
#ink.panning{cursor:grabbing}
#ink.readonly{cursor:not-allowed}

.stage-empty{
  position:absolute;inset:0;display:flex;flex-direction:column;align-items:center;justify-content:center;
  gap:6px;color:var(--muted);pointer-events:none;text-align:center;padding:20px;
}
.stage-empty .se-ico{font-size:40px;opacity:.5}
.stage-empty h3{margin:0;font-size:16px;color:var(--text-2);font-weight:700}
.stage-empty p{margin:0;font-size:13px;max-width:340px}

/* 底部 dock */
.dock{
  position:absolute;bottom:16px;left:50%;transform:translateX(-50%);
  display:flex;align-items:center;gap:6px;padding:6px;
  background:rgba(255,255,255,.94);backdrop-filter:blur(14px);
  border:1px solid var(--line);border-radius:13px;box-shadow:var(--shadow);
  z-index:12;max-width:calc(100% - 24px);
}
.dock-group{display:flex;align-items:center;gap:3px}
.dock-div{width:1px;height:20px;background:var(--line)}
.dock-btn{
  height:32px;min-width:32px;padding:0 9px;border-radius:8px;font-size:13px;font-weight:600;
  color:var(--text-2);display:inline-flex;align-items:center;justify-content:center;transition:.14s;
}
.dock-btn:hover{background:var(--panel-2);color:var(--text)}
.dock-btn:disabled{opacity:.3;cursor:not-allowed}
.dock-btn:disabled:hover{background:none}
.zoom-val{font-family:var(--mono);font-size:12px;min-width:52px}
.page-ind{font-family:var(--mono);font-size:12px;color:var(--text-2);min-width:56px;text-align:center}
.follow-btn{display:none;font-size:12.5px}
body.is-student .follow-btn{display:inline-flex}
.follow-btn.on{background:var(--brand-soft);color:var(--brand)}

/* 连麦语音 */
.mic-btn{gap:6px;position:relative;overflow:hidden;min-width:70px}
.mic-btn .mic-ico{font-size:14px;line-height:1;font-style:normal}
.mic-btn .mic-label{font-size:12.5px;font-weight:700;white-space:nowrap}
.mic-btn.on{background:#e8f7ee;color:#067647}
.mic-btn.wait{background:#fff4e5;color:#b25e00}
.mic-btn.err{background:#fee4e2;color:#b42318}
.mic-btn.wave .mic-ico{animation:micPulse 1s infinite}
@keyframes micPulse{0%,100%{opacity:1;transform:scale(1)}50%{opacity:.5;transform:scale(1.14)}}
.mic-level{
  position:absolute;left:0;bottom:0;height:2.5px;width:0;background:currentColor;
  opacity:.75;transition:width .1s linear;
}
.audio-hint{
  position:fixed;left:50%;transform:translateX(-50%);bottom:74px;z-index:130;
  background:rgba(15,23,42,.92);color:#fff;border:0;border-radius:10px;
  padding:9px 16px;font-size:13px;font-weight:600;box-shadow:var(--shadow-lg);cursor:pointer;
  animation:dropIn .3s ease both;
}

/* 摄像头按钮：沿用连麦按钮的形态，只换配色（蓝 = 视频，绿 = 音频） */
.cam-btn{min-width:96px}
.cam-btn.on{background:#e8f1fe;color:#1d4ed8}
.cam-btn.wait .mic-ico{animation:micPulse 1s infinite}
.cam-btn.busy{opacity:.6}

/* ───────────── 视频墙 ───────────── */
.video-wall{
  position:absolute;top:12px;left:12px;z-index:11;
  width:238px;max-height:calc(100% - 24px);
  background:rgba(255,255,255,.96);backdrop-filter:blur(14px);
  border:1px solid var(--line);border-radius:13px;box-shadow:var(--shadow);
  display:flex;flex-direction:column;overflow:hidden;
  animation:vwIn .24s ease both;
}
@keyframes vwIn{from{opacity:0;transform:translateY(-6px)}to{opacity:1;transform:translateY(0)}}
.video-wall.folded .vw-grid{display:none}
.vw-head{
  display:flex;align-items:center;justify-content:space-between;gap:8px;
  padding:7px 10px;border-bottom:1px solid var(--line);
  font-size:12px;font-weight:700;color:var(--text-2);
}
.vw-head b{color:var(--brand);font-family:var(--mono)}
.vw-fold{
  width:20px;height:20px;border-radius:6px;font-size:13px;font-weight:700;line-height:1;
  color:var(--text-2);
}
.vw-fold:hover{background:var(--panel-2);color:var(--text)}
.vw-grid{
  display:flex;flex-direction:column;gap:8px;padding:8px;
  overflow-y:auto;overscroll-behavior:contain;
}
.vw-tile{
  position:relative;border-radius:10px;overflow:hidden;background:#0f172a;
  aspect-ratio:16/10;flex:0 0 auto;
}
.vw-tile video{width:100%;height:100%;object-fit:cover;display:block;background:#0f172a}
.vw-tile .vw-ph{
  position:absolute;inset:0;display:none;flex-direction:column;align-items:center;justify-content:center;gap:6px;
  background:#eef2f7;color:var(--muted);font-size:11px;
}
.vw-tile:not(.live) .vw-ph{display:flex}
.vw-tile .vw-ph .av{
  width:34px;height:34px;border-radius:11px;display:grid;place-items:center;
  color:#fff;font-weight:700;font-size:13px;
}
.vw-name{
  position:absolute;left:6px;bottom:6px;max-width:calc(100% - 12px);
  padding:2px 7px;border-radius:6px;background:rgba(15,23,42,.62);color:#fff;
  font-size:11px;font-weight:600;white-space:nowrap;overflow:hidden;text-overflow:ellipsis;
}
.vw-badge{
  position:absolute;right:6px;top:6px;padding:2px 6px;border-radius:6px;
  background:rgba(47,111,237,.92);color:#fff;font-size:10.5px;font-weight:700;
}
@media (max-width:720px){
  .video-wall{width:152px}
}

.draft-flag{
  position:absolute;top:12px;left:50%;transform:translateX(-50%);
  background:rgba(255,244,229,.97);border:1px solid #ffdfae;color:#8a4b00;
  padding:7px 14px;border-radius:10px;font-size:12.5px;box-shadow:var(--shadow-sm);
  z-index:11;max-width:calc(100% - 30px);text-align:center;
  animation:dropIn .3s ease both;
}
@keyframes dropIn{from{opacity:0;transform:translate(-50%,-8px)}to{opacity:1;transform:translate(-50%,0)}}

/* ───────────── 右侧栏 ───────────── */
.sidebar{
  width:290px;flex:0 0 290px;background:var(--panel);border-left:1px solid var(--line);
  display:flex;flex-direction:column;min-height:0;z-index:15;transition:.2s;
}
.sidebar.collapsed{width:0;flex-basis:0;border-left:0;overflow:hidden}
.side-tabs{display:flex;border-bottom:1px solid var(--line);padding:0 6px;flex:0 0 auto}
.stab{
  flex:1;height:42px;font-size:13px;font-weight:600;color:var(--muted);
  border-bottom:2px solid transparent;display:inline-flex;align-items:center;justify-content:center;gap:5px;
}
.stab i{font-style:normal;font-size:10.5px;background:var(--line-2);border-radius:999px;padding:1px 6px;color:var(--muted);font-weight:700}
.stab.active{color:var(--brand);border-bottom-color:var(--brand)}
.stab.active i{background:var(--brand-soft);color:var(--brand)}
.stab i.hot{background:#ffe4e0;color:#c4321f}
.side-pane{display:none;flex:1;min-height:0;flex-direction:column;overflow:hidden}
.side-pane.active{display:flex}

/* 成员 */
.members{flex:1;overflow-y:auto;padding:8px}
.member{
  display:flex;align-items:center;gap:9px;padding:7px 9px;border-radius:10px;transition:.14s;
  /* 窄屏时按钮整组换到第二行，而不是把名字和角色文字挤成竖排 */
  flex-wrap:wrap;row-gap:5px;
}
.member:hover{background:var(--panel-2)}
.member .av{
  width:30px;height:30px;border-radius:9px;flex:0 0 30px;display:grid;place-items:center;
  color:#fff;font-weight:700;font-size:12.5px;
}
/* min-width 必须是个实数：只写 min-width:0 的话，窄屏会把这一列压到只剩几个像素，
   于是「已授权书写」这种角色文字就变成一字一行竖着排。 */
.member .mi{flex:1 1 92px;min-width:92px}
.member .mn{font-size:13px;font-weight:600;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
.member .mr{
  font-size:11px;color:var(--muted);
  white-space:nowrap;overflow:hidden;text-overflow:ellipsis;max-width:100%;
}
/* 按钮自成一组，换行时整组一起走，不会散开 */
.member .m-acts{display:flex;gap:5px;flex:0 0 auto;margin-left:auto}
.member .hand-tag{font-size:15px;animation:wave 1.1s infinite;flex:0 0 auto}
@keyframes wave{0%,100%{transform:rotate(-8deg)}50%{transform:rotate(12deg)}}
.member .mini-btn{
  height:25px;padding:0 7px;border-radius:7px;font-size:11px;font-weight:700;
  background:var(--brand-soft);color:var(--brand);border:1px solid #d7e3ff;white-space:nowrap;
}
.member .mini-btn:hover{background:#e0eaff}
.member .mini-btn.warn{background:#fff4e5;color:#b25e00;border-color:#ffdfae}
.member .mini-btn.mic{background:#e8f7ee;color:#067647;border-color:#b7e4c7}
.member .mini-btn.mic:hover{background:#d7f0e1}
.member .mini-btn.mic.on{background:#067647;color:#fff;border-color:#067647}
.member .mini-btn.cam{background:#e8f1fe;color:#1d4ed8;border-color:#c3d9fd}
.member .mini-btn.cam:hover{background:#dbe8fe}
.member .mini-btn.cam.on{background:#1d4ed8;color:#fff;border-color:#1d4ed8}
.member .mic-tag{font-size:14px}
.member .cam-tag{font-size:14px}
/* 正在发言的人整行点亮，老师一眼看到谁在说 */
.member.speaking{background:#e8f7ee;box-shadow:inset 0 0 0 1px #b7e4c7}
.member.speaking .mr{color:#067647;font-weight:600}

/* 已离线：整行置灰并排在列表最后，一眼区分「还在课堂」和「已经走了」 */
.member.offline{opacity:.6}
.member.offline .av{background:#b6bfcd !important;filter:grayscale(1)}
.member.offline .mn{color:var(--muted);font-weight:600}
.member.offline .mr{color:#9aa4b2}
.member.offline:hover{background:var(--panel-2)}
.member .off-tag{
  flex:0 0 auto;font-size:10.5px;font-weight:700;color:#7c8798;
  background:#eef1f6;border-radius:999px;padding:1px 7px;
}
.member.kicked .off-tag{background:#fef2f2;color:#b42318}
.m-sep{display:flex;align-items:center;gap:8px;padding:12px 9px 4px;font-size:11px;font-weight:600;color:var(--muted)}
.m-sep::after{content:"";flex:1;height:1px;background:var(--line)}
.perm-box{flex:0 0 auto;border-top:1px solid var(--line);padding:12px;background:var(--panel-2)}
.switch-row{display:flex;align-items:center;justify-content:space-between;font-size:13px;font-weight:600;gap:10px}
.switch-row input{width:38px;height:21px;appearance:none;background:#d5dbe6;border-radius:99px;position:relative;transition:.18s;cursor:pointer;flex:0 0 38px}
.switch-row input::after{content:"";position:absolute;top:2.5px;left:2.5px;width:16px;height:16px;border-radius:50%;background:#fff;transition:.18s;box-shadow:0 1px 3px rgba(0,0,0,.2)}
.switch-row input:checked{background:var(--brand)}
.switch-row input:checked::after{transform:translateX(17px)}
.perm-hint{margin:8px 0 0;font-size:11.5px;color:var(--muted);line-height:1.6}

/* 聊天 */
.chat-list{flex:1;overflow-y:auto;padding:12px 10px;display:flex;flex-direction:column;gap:10px}
.chat-msg{display:flex;gap:8px;animation:fadeIn .2s ease both}
.chat-msg .av{width:26px;height:26px;border-radius:8px;flex:0 0 26px;display:grid;place-items:center;color:#fff;font-size:11.5px;font-weight:700}
.chat-body{flex:1;min-width:0}
.chat-meta{font-size:11px;color:var(--muted);margin-bottom:2px;display:flex;gap:6px;align-items:center}
.chat-meta .tag{background:#eef1f6;border-radius:4px;padding:0 5px;font-weight:700;font-size:10px}
.chat-meta .tag.t{background:#fff2d6;color:#a05a00}
.chat-text{background:var(--panel-2);border-radius:3px 10px 10px 10px;padding:7px 11px;font-size:13px;word-break:break-word;white-space:pre-wrap}
.chat-msg.mine .chat-text{background:var(--brand-soft)}
.chat-msg.sys{justify-content:center}
.chat-msg.sys .chat-text{background:none;color:var(--muted);font-size:11.5px;text-align:center;padding:2px}
.chat-form{flex:0 0 auto;display:flex;gap:7px;padding:9px 10px 0;border-top:1px solid var(--line);margin-top:auto}
.chat-form input{flex:1;height:38px;padding:0 12px;border-radius:9px;border:1px solid var(--line);outline:none;background:var(--panel-2)}
.chat-form input:focus{border-color:var(--brand);background:#fff;box-shadow:0 0 0 3px rgba(47,111,237,.12)}
.chat-form .btn{height:38px}
.quick-row{display:flex;gap:6px;padding:8px 10px 11px;flex-wrap:wrap}
.quick{height:26px;padding:0 10px;border-radius:999px;font-size:11.5px;background:var(--panel-2);border:1px solid var(--line);color:var(--text-2)}
.quick:hover{border-color:var(--brand);color:var(--brand);background:var(--brand-soft)}

/* 文档列表 */
.doc-list{flex:1;overflow-y:auto;padding:9px;display:flex;flex-direction:column;gap:7px}
.doc-item{
  display:flex;align-items:center;gap:9px;padding:9px;border-radius:10px;
  border:1px solid var(--line);background:var(--panel-2);transition:.15s;cursor:pointer;
}
.doc-item:hover{border-color:#cfdaf0;background:#fff}
.doc-item.active{border-color:var(--brand);background:var(--brand-soft);box-shadow:0 0 0 2.5px rgba(47,111,237,.11)}
.doc-item .di-ico{width:30px;height:34px;border-radius:6px;display:grid;place-items:center;font-size:14px;color:#fff;font-weight:700;flex:0 0 30px}
.doc-item .di-main{flex:1;min-width:0}
.doc-item .di-n{font-size:12.5px;font-weight:600;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
.doc-item .di-s{font-size:11px;color:var(--muted);margin-top:1px}
.doc-item .di-del{width:24px;height:24px;border-radius:6px;color:var(--muted);font-size:14px;display:grid;place-items:center;flex:0 0 auto}
.doc-item .di-del:hover{background:#ffe9e6;color:var(--red)}
.doc-empty{padding:28px 16px;text-align:center;color:var(--muted);font-size:12.5px}

/* ───────────── 上传进度 / 弹窗 / 提示 ───────────── */
.progress-wrap{position:fixed;inset:0;z-index:80;display:grid;place-items:center;background:rgba(15,23,42,.32);backdrop-filter:blur(3px)}
.progress-card{width:min(400px,92vw);background:#fff;border-radius:16px;padding:22px;box-shadow:var(--shadow-lg)}
.pv-head{display:flex;justify-content:space-between;font-size:14px;font-weight:700;margin-bottom:11px}
.pv-head b{font-family:var(--mono);color:var(--brand)}
.pv-bar{height:8px;border-radius:99px;background:var(--line-2);overflow:hidden}
.pv-bar i{display:block;height:100%;width:0;border-radius:99px;background:linear-gradient(90deg,var(--brand-2),var(--brand));transition:width .25s}
.pv-sub{margin-top:10px;font-size:12px;color:var(--muted);min-height:16px}

.modal-wrap{position:fixed;inset:0;z-index:90;display:grid;place-items:center;background:rgba(15,23,42,.34);backdrop-filter:blur(3px);padding:20px}
.modal{width:min(470px,100%);background:#fff;border-radius:18px;padding:24px;box-shadow:var(--shadow-lg);animation:gateIn .28s cubic-bezier(.2,.8,.3,1) both}
.modal h3{margin:0 0 6px;font-size:18px}
.modal-sub{margin:0 0 18px;font-size:12.5px;color:var(--muted)}
.copy-row{display:flex;gap:8px}
.copy-row input{flex:1;font-family:var(--mono);font-size:12.5px;background:var(--panel-2)}
.copy-row .btn{height:44px;padding:0 16px}
.modal-foot{display:flex;justify-content:flex-end;margin-top:6px}

.toasts{position:fixed;top:66px;left:50%;transform:translateX(-50%);z-index:120;display:flex;flex-direction:column;gap:8px;align-items:center;pointer-events:none}
.toast{
  background:rgba(15,23,42,.9);color:#fff;padding:9px 16px;border-radius:10px;font-size:13px;
  box-shadow:var(--shadow);animation:tIn .24s cubic-bezier(.2,.8,.3,1) both;max-width:80vw;
}
.toast.ok{background:rgba(6,118,71,.94)}
.toast.warn{background:rgba(180,83,9,.94)}
.toast.err{background:rgba(180,35,24,.94)}
@keyframes tIn{from{opacity:0;transform:translateY(-10px) scale(.96)}to{opacity:1;transform:none}}
.toast.out{animation:tOut .22s ease both}
@keyframes tOut{to{opacity:0;transform:translateY(-8px) scale(.96)}}

.doc-warning{
  position:absolute;top:50%;left:50%;transform:translate(-50%,-50%);
  background:#fff;border-radius:14px;padding:22px 26px;box-shadow:var(--shadow-lg);
  max-width:min(420px,86vw);text-align:center;z-index:14;font-size:13px;line-height:1.7;
  pointer-events:none;
}
.doc-warning b{display:block;margin-bottom:6px;font-size:15px}
.doc-warning .muted{color:var(--muted);font-size:12px}

/* 学生模式隐藏老师专属 */
.student-only{display:none}
body.is-student .student-only{display:flex}
body.is-student [data-teacher-only]{display:none !important}
.teacher-only{display:none}
body.is-teacher .teacher-only{display:block}
.dock-group.teacher-only{display:none}
body.is-teacher .dock-group.teacher-only{display:flex}

/* 响应式 */
@media(max-width:900px){
  .sidebar{position:absolute;right:0;top:0;bottom:0;width:270px;flex-basis:270px;box-shadow:-8px 0 26px rgba(16,24,40,.11)}
  .sidebar.collapsed{transform:translateX(100%);width:270px;flex-basis:270px}
  .toolbar{width:58px;flex-basis:58px}
  .tool{width:44px;height:44px}
  .tool em{font-size:9px}
  .tool-group.colors{width:48px;gap:6px}
  .tool-group.sizes{width:48px;gap:4px}
  .rt-name{max-width:26vw}
}

@media(max-width:640px){
  .topbar{padding:0 9px;gap:6px}
  .tb-left{gap:8px;overflow:hidden}
  .rt-name{max-width:30vw;font-size:13.5px}
  .rt-sub{white-space:nowrap;overflow:hidden;text-overflow:ellipsis;gap:4px}
  .chip-code{display:none}
  #btnRoomExpire{display:none}
  #onlineCount,.sep{display:none}
  .brand-mini{display:none}
  .tb-right{gap:6px;flex:0 0 auto}
  .btn{height:34px;padding:0 10px;font-size:12.5px}
  #btnShare{padding:0 11px}
  .role-badge{display:none}
  .dock{bottom:10px;gap:4px;padding:5px;flex-wrap:wrap;justify-content:center;max-width:calc(100% - 16px);row-gap:3px}
  .dock-div{display:none}
  .dock-btn{height:30px;min-width:30px;padding:0 6px}
  .follow-btn{flex:1 0 auto;justify-content:center}
  .zoom-val{min-width:44px}
  .page-ind{min-width:46px}
  .gate-card{padding:22px 18px 18px;border-radius:18px}
  .gate-head h1{font-size:22px}
  .gate-feats{gap:8px}
  .feat{padding:10px 11px}
  .code-input{font-size:18px;letter-spacing:5px}
}

/* ═══════════════════════════════════════════════════
   账号体系：入口页扩展 / 工作台 / 管理控制台
   ═══════════════════════════════════════════════════ */

/* ───────── 通用小组件 ───────── */
.mini-link{
  font-size:12px;font-weight:600;color:var(--brand);
  padding:2px 6px;border-radius:6px;
}
.mini-link:hover{background:var(--brand-soft)}
.notice{
  display:flex;flex-direction:column;gap:3px;
  border-radius:10px;padding:11px 13px;font-size:12.5px;line-height:1.65;
  border:1px solid transparent;margin-bottom:14px;
}
.notice b{font-size:13px}
.notice.warn{background:#fff8ec;border-color:#ffe2b8;color:#8a5300}
.notice.ok{background:#eefaf3;border-color:#c8efd9;color:#076a41}
.notice.info{background:var(--brand-soft);border-color:#d7e3ff;color:#1c4fb8}
.notice code{font-family:var(--mono);font-size:11.5px;background:rgba(15,23,42,.06);padding:1px 5px;border-radius:5px}
.gate-hint code{font-family:var(--mono);font-size:11px;background:rgba(15,23,42,.06);padding:1px 4px;border-radius:4px}

/* 首次初始化 */
.setup-head{display:flex;flex-direction:column;gap:4px;margin-bottom:16px}
.setup-head b{font-size:15px}
.setup-head span{font-size:12.5px;color:var(--muted);line-height:1.6}

/* ───────── 老师面板 ───────── */
.who{display:flex;align-items:center;gap:11px;padding:11px 13px;border:1px solid var(--line);border-radius:12px;background:var(--panel-2);margin-bottom:16px}
.who .av{width:38px;height:38px;border-radius:11px;flex:0 0 auto;display:grid;place-items:center;color:#fff;font-weight:700;font-size:14px;background:linear-gradient(135deg,var(--brand-2),var(--brand))}
.who-txt{flex:1;min-width:0}
.who-name{font-weight:700;font-size:14px;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}
.who-role{font-size:11.5px;color:var(--muted)}
.who-role.admin{color:var(--violet);font-weight:600}
.btn-console{background:linear-gradient(135deg,#7c5cff,#5b8cff);color:#fff;border-color:transparent;box-shadow:0 2px 10px rgba(124,92,255,.28)}
.btn-console:hover{filter:brightness(1.05);background:linear-gradient(135deg,#7c5cff,#5b8cff)}

.work-rooms{margin-top:18px;border-top:1px solid var(--line-2);padding-top:14px}
.wr-head{display:flex;align-items:center;justify-content:space-between;font-size:12.5px;font-weight:700;color:var(--text-2);margin-bottom:9px}
.wr-list{display:flex;flex-direction:column;gap:7px;max-height:190px;overflow-y:auto}
.wr-empty{font-size:12.5px;color:var(--muted);padding:8px 2px}
.wr-item{
  display:flex;align-items:center;gap:9px;
  border:1px solid var(--line);border-radius:10px;padding:9px 11px;background:#fff;
  transition:.15s;
}
.wr-item:hover{border-color:#cfd9ec;background:var(--panel-2)}
.wr-item .wri-main{flex:1;min-width:0}
.wr-item .wri-name{font-weight:600;font-size:13px;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}
.wr-item .wri-sub{font-size:11.5px;color:var(--muted);display:flex;gap:7px;flex-wrap:wrap;margin-top:2px}
.wr-item .wri-code{font-family:var(--mono);font-weight:700;color:var(--brand);letter-spacing:.6px}
.wri-live{color:var(--green);font-weight:600}
.wri-acts{display:flex;gap:5px;flex:0 0 auto;flex-wrap:wrap;justify-content:flex-end}
.wri-exp{color:var(--text-2);font-weight:600}
.wri-exp.warn{color:#b45309}
.wri-exp.bad{color:#b42318;font-weight:700}
.wr-item.is-expired{background:#fafbfd;border-style:dashed}
.wr-item.is-expired .wri-name{color:var(--muted)}
.btn.btn-danger{color:#b42318;border-color:#f2cdc9;background:#fef7f6}
.btn.btn-danger:hover{background:#fdecea;border-color:#eab0a9}
.chip-exp{background:#fff7ed;color:#b45309;font-weight:600;border:1px solid #fde3c4}
.chip-exp b{font-family:var(--mono);letter-spacing:.4px}
.chip-exp.warn{background:#fef3c7;color:#92400e;border-color:#fcd88a}
.chip-exp.bad{background:#fef2f2;color:#b42318;border-color:#f7cdc9}
.chip-exp:hover{filter:brightness(.97)}
.choose-hint{margin:0 0 12px;font-size:12.5px;line-height:1.75;color:var(--text-2)}
.choose-hint b{color:var(--text)}

.room-tip{
  background:var(--brand-soft);border:1px solid #d7e3ff;border-radius:10px;
  padding:9px 12px;font-size:12.5px;color:#1c4fb8;margin-bottom:14px;line-height:1.6;
}

/* ───────── 分享弹窗：邮件发送 ───────── */
.modal-wide{width:min(560px,100%);max-height:calc(100vh - 40px);overflow-y:auto}
.mail-block{border-top:1px solid var(--line-2);margin-top:18px;padding-top:16px}
.mail-head{display:flex;align-items:center;justify-content:space-between;font-size:13.5px;font-weight:700;margin-bottom:10px}
.mail-state{font-size:11.5px;font-weight:600;color:var(--muted)}
.mail-state.ok{color:var(--green)}
.mail-state.off{color:var(--amber)}
.rcp-pick{border:1px solid var(--line);border-radius:11px;overflow:hidden;margin-bottom:14px}
.rcp-top{display:flex;align-items:center;gap:8px;padding:8px 10px;background:var(--panel-2);border-bottom:1px solid var(--line-2)}
.rcp-top input{flex:1;height:30px;border:1px solid var(--line);border-radius:8px;padding:0 10px;font-size:12.5px;background:#fff}
.rcp-top input:focus{outline:none;border-color:var(--brand);box-shadow:0 0 0 3px rgba(47,111,237,.12)}
.rcp-list{max-height:168px;overflow-y:auto;padding:5px}
.rcp-empty{font-size:12.5px;color:var(--muted);padding:14px 10px;text-align:center}
.rcp-item{display:flex;align-items:center;gap:9px;padding:6px 8px;border-radius:8px;cursor:pointer;transition:.12s}
.rcp-item:hover{background:var(--panel-2)}
.rcp-item input{width:15px;height:15px;accent-color:var(--brand);flex:0 0 auto}
.rcp-item .rcp-av{width:24px;height:24px;border-radius:7px;display:grid;place-items:center;color:#fff;font-size:10.5px;font-weight:700;flex:0 0 auto}
.rcp-item .rcp-info{flex:1;min-width:0;line-height:1.35}
.rcp-item .rcp-name{font-size:12.5px;font-weight:600;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}
.rcp-item .rcp-mail{font-size:11px;color:var(--muted);overflow:hidden;text-overflow:ellipsis;white-space:nowrap}
.rcp-item .rcp-dept{font-size:11px;color:var(--muted);flex:0 0 auto;max-width:88px;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}
.rcp-foot{display:flex;align-items:center;gap:8px;padding:7px 10px;border-top:1px solid var(--line-2);background:var(--panel-2);font-size:11.5px;color:var(--muted)}
.rcp-foot #rcpCount{margin-right:auto;font-weight:600;color:var(--text-2)}
.field textarea{
  width:100%;border:1px solid var(--line);border-radius:10px;padding:9px 11px;
  font-size:13.5px;line-height:1.6;resize:vertical;background:#fff;
}
.field textarea:focus{outline:none;border-color:var(--brand);box-shadow:0 0 0 3.5px rgba(47,111,237,.14)}
.mail-foot{display:flex;justify-content:flex-end;margin-top:4px}
.mail-result{margin-top:12px;border-radius:10px;padding:11px 13px;font-size:12.5px;line-height:1.7;border:1px solid var(--line);background:var(--panel-2);max-height:150px;overflow-y:auto}
.mail-result .mr-bad{color:var(--red)}
.mail-result .mr-ok{color:var(--green)}
.mail-result .mr-sim{color:var(--amber)}

/* ───────── 管理控制台 ───────── */
.console{position:fixed;inset:0;z-index:100;background:var(--bg);display:flex;flex-direction:column}
.console-top{
  display:flex;align-items:center;gap:16px;padding:0 18px;height:58px;flex:0 0 auto;
  background:#fff;border-bottom:1px solid var(--line);
}
.ct-left{display:flex;align-items:baseline;gap:9px}
.ct-left b{font-size:15.5px}
.ct-who{font-size:12px;color:var(--muted)}
.ct-nav{display:flex;gap:4px;margin-left:8px;flex:1}
.ct-nav button{height:34px;padding:0 14px;border-radius:9px;font-size:13.5px;font-weight:600;color:var(--text-2);transition:.15s}
.ct-nav button:hover{background:var(--panel-2)}
.ct-nav button.active{background:var(--brand-soft);color:var(--brand)}
.console-body{flex:1;overflow-y:auto;padding:20px;max-width:1240px;width:100%;margin:0 auto}
.cs-pane{display:none}
.cs-pane.active{display:block;animation:fadeIn .2s ease both}
.cs-toolbar{display:flex;align-items:center;gap:9px;flex-wrap:wrap;margin-bottom:14px}
.cs-search{height:36px;border:1px solid var(--line);border-radius:9px;padding:0 12px;width:250px;font-size:13.5px;background:#fff}
.cs-search:focus{outline:none;border-color:var(--brand);box-shadow:0 0 0 3.5px rgba(47,111,237,.14)}
.cs-toolbar select{height:36px;border:1px solid var(--line);border-radius:9px;padding:0 9px;font-size:13.5px;background:#fff}
.cs-note{background:#fff;border:1px solid var(--line);border-radius:12px;padding:14px 16px;margin-bottom:16px;display:flex;flex-direction:column;gap:5px}
.cs-note b{font-size:14.5px}
.cs-note span{font-size:12.5px;color:var(--text-2);line-height:1.7}
.cs-hint{font-size:12px;color:var(--muted)}
.cs-stats{display:flex;gap:10px;flex-wrap:wrap;margin-bottom:14px}
.cs-stat{background:#fff;border:1px solid var(--line);border-radius:10px;padding:9px 14px;min-width:86px}
.cs-stat b{display:block;font-size:19px;line-height:1.25}
.cs-stat span{font-size:11.5px;color:var(--muted)}
.cs-stat.hot b{color:var(--amber)}
.cs-tablewrap{background:#fff;border:1px solid var(--line);border-radius:12px;overflow-x:auto}
.cs-table{width:100%;border-collapse:collapse;font-size:13px;min-width:720px}
.cs-table th{
  text-align:left;font-size:12px;font-weight:600;color:var(--muted);
  padding:11px 12px;border-bottom:1px solid var(--line);background:var(--panel-2);white-space:nowrap;
}
.cs-table td{padding:10px 12px;border-bottom:1px solid var(--line-2);vertical-align:middle}
.cs-table tr:last-child td{border-bottom:0}
.cs-table tr:hover td{background:#fafcff}
.cs-table .td-name{font-weight:600}
.cs-table .td-mail{font-family:var(--mono);font-size:12px;color:var(--text-2)}
.cs-table .td-acts{display:flex;gap:5px;flex-wrap:wrap}
.cs-table .row-actions button{
  height:27px;padding:0 9px;border-radius:7px;font-size:11.5px;font-weight:600;
  background:var(--panel-2);border:1px solid var(--line);color:var(--text-2);
}
.cs-table .row-actions button:hover{background:var(--brand-soft);border-color:#d7e3ff;color:var(--brand)}
.cs-table .row-actions button.pri{background:var(--brand-soft);border-color:#d7e3ff;color:var(--brand)}
.cs-table .row-actions button.danger:hover{background:#fef2f1;border-color:#fbd5d1;color:var(--red)}
.tag{display:inline-block;padding:1px 7px;border-radius:999px;font-size:11px;font-weight:600;white-space:nowrap}
.tag-admin{background:#f2eeff;color:#6d28d9}
.tag-teacher{background:var(--brand-soft);color:var(--brand)}
.tag-student{background:#f1f4f9;color:var(--text-2)}
.tag-active{background:#eafaf1;color:#067647}
.tag-pending{background:#fff6e8;color:#b25e00}
.tag-disabled{background:#fef2f1;color:var(--red)}
.tag-nohost{background:#f1f4f9;color:var(--muted)}
.cs-empty{padding:34px;text-align:center;color:var(--muted);font-size:13px}
/* 上课记录表：课堂名下面那行小字（课堂码）与「进行中」标记 */
.cs-sub{color:var(--muted);font-size:11.5px;font-family:var(--mono)}
.tag-live{display:inline-block;padding:1px 8px;border-radius:999px;font-size:11px;font-weight:600;background:#eafaf1;color:#067647}
.cs-textarea{
  width:100%;min-height:230px;border:1px solid var(--line);border-radius:12px;padding:13px 15px;
  font-family:var(--mono);font-size:12.5px;line-height:1.75;resize:vertical;background:#fff;
}
.cs-textarea:focus{outline:none;border-color:var(--brand);box-shadow:0 0 0 3.5px rgba(47,111,237,.14)}
.cs-check,.cs-inline{display:inline-flex;align-items:center;gap:6px;font-size:13px;color:var(--text-2)}
.cs-check input{width:15px;height:15px;accent-color:var(--brand)}
.cs-inline select{height:32px;border:1px solid var(--line);border-radius:8px;padding:0 8px;font-size:13px;background:#fff}
.cs-form{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:13px 16px;background:#fff;border:1px solid var(--line);border-radius:12px;padding:16px;margin-bottom:16px}
.cs-field{display:flex;flex-direction:column;gap:5px}
.cs-field span{font-size:12px;font-weight:600;color:var(--text-2)}
.cs-field input,.cs-field select{
  height:36px;border:1px solid var(--line);border-radius:9px;padding:0 11px;font-size:13.5px;background:#fff;
}
.cs-field input:focus,.cs-field select:focus{outline:none;border-color:var(--brand);box-shadow:0 0 0 3.5px rgba(47,111,237,.14)}
.cs-report{background:#fff;border:1px solid var(--line);border-radius:12px;padding:15px 17px;font-size:13px;line-height:1.8;margin-top:14px}
.cs-report b{font-size:14.5px}
.cs-report .rp-row{display:flex;gap:14px;flex-wrap:wrap;margin:8px 0 12px}
.cs-report .rp-k{background:var(--panel-2);border-radius:9px;padding:7px 12px;font-size:12.5px}
.cs-report .rp-k b{font-size:17px;display:block}
.cs-report table{width:100%;border-collapse:collapse;font-size:12.5px;margin-top:8px}
.cs-report th{text-align:left;color:var(--muted);font-weight:600;padding:7px 9px;border-bottom:1px solid var(--line)}
.cs-report td{padding:7px 9px;border-bottom:1px solid var(--line-2);vertical-align:top}
.cs-report .pw{font-family:var(--mono);font-weight:700;color:var(--brand)}
.cs-report summary{cursor:pointer;font-weight:600;color:var(--brand);font-size:12.5px;margin-top:10px}
.cs-report .rp-bad{color:var(--red)}
.cs-report .rp-ok{color:var(--green)}
.cs-report .rp-sim{color:var(--amber)}

@media(max-width:760px){
  .ct-nav{overflow-x:auto;flex-wrap:nowrap}
  .ct-nav button{padding:0 10px;font-size:12.5px}
  .console-body{padding:14px 12px}
  .cs-form{grid-template-columns:1fr}
  .cs-search{width:100%}
  .console-top{height:auto;padding:9px 12px;flex-wrap:wrap;gap:9px}
  .ct-left{width:100%}
  .ct-nav{order:3;width:100%;margin-left:0}
}

/* 控制台内的自绘表单 / 危险按钮 */
.btn-danger{background:linear-gradient(180deg,#f97066,#e2382b);color:#fff;border-color:transparent;box-shadow:0 2px 8px rgba(226,56,43,.26)}
.btn-danger:hover{filter:brightness(1.05);background:linear-gradient(180deg,#f97066,#e2382b)}
.ui-form .field:last-child{margin-bottom:4px}
.ui-form .field select{
  width:100%;height:40px;border:1px solid var(--line);border-radius:10px;padding:0 11px;
  font-size:13.5px;background:#fff;
}
.ui-form .field select:focus{outline:none;border-color:var(--brand);box-shadow:0 0 0 3.5px rgba(47,111,237,.14)}
.ui-form-msg{margin:2px 0 8px}

/* ═══════════════════════════════════════════════════
   文字工具 / 二维码 / 退出课堂 / 音视频自检
   ═══════════════════════════════════════════════════ */

/* ───────── 文字输入框（浮在画布上，输入完才落成对象） ───────── */
.text-input{
  position:absolute;z-index:9;
  min-width:80px;min-height:32px;
  padding:5px 8px;border-radius:8px;
  border:1.5px dashed var(--brand);
  background:rgba(255,255,255,.95);
  box-shadow:0 6px 22px rgba(16,24,40,.16);
  outline:none;resize:none;overflow:hidden;
  white-space:pre-wrap;word-break:break-word;
  font-weight:600;
  caret-color:var(--brand);
}
.text-input::placeholder{color:#b6bfcd;font-weight:500}

/* 文字工具下画布光标跟着语义走：空白处是文本光标，框上是移动，角上是缩放 */
#ink.text-tool{cursor:text}

/* ───────── 分享弹窗里的二维码 ───────── */
.qr-box{
  display:flex;gap:14px;align-items:center;
  border:1px solid var(--line);border-radius:12px;padding:12px;
  background:var(--panel-2);margin-bottom:16px;
}
.qr-canvas-wrap{
  flex:0 0 auto;background:#fff;border:1px solid var(--line);border-radius:10px;
  padding:6px;line-height:0;box-shadow:var(--shadow-sm);
}
.qr-canvas-wrap canvas{display:block;max-width:100%;height:auto}
.qr-side{flex:1;min-width:0;display:flex;flex-direction:column;gap:5px}
.qr-side b{font-size:13.5px}
.qr-side span{font-size:11.5px;color:var(--muted);line-height:1.65}
.qr-acts{display:flex;gap:12px;margin-top:3px;flex-wrap:wrap}
@media(max-width:560px){
  .qr-box{flex-direction:column;align-items:center;text-align:center}
  .qr-side{align-items:center}
  .qr-acts{justify-content:center}
}

/* ───────── 退出课堂 ───────── */
.btn-leave{color:#b42318}
.btn-leave:hover{background:#fef6f5;border-color:#fbd5d1;color:#912018}
body.is-teacher .btn-leave{color:#b25e00}
body.is-teacher .btn-leave:hover{background:#fff8ec;border-color:#ffdfae;color:#8a5300}
@media(max-width:640px){
  .btn-leave{padding:0 9px;font-size:12px}
}

/* ───────── 控制台：音视频设置 ───────── */
.cs-field .cs-ta{
  min-height:74px;border:1px solid var(--line);border-radius:9px;padding:8px 11px;
  font-family:var(--mono);font-size:12px;line-height:1.75;resize:vertical;background:#fff;
}
.cs-field .cs-ta:focus{outline:none;border-color:var(--brand);box-shadow:0 0 0 3.5px rgba(47,111,237,.14)}
.rp-grid{display:flex;flex-wrap:wrap;gap:10px;margin:12px 0}
.rp-card{
  border:1px solid var(--line);border-radius:10px;padding:9px 13px;min-width:118px;
  background:var(--panel-2);
}
.rp-card b{display:block;font-size:17px;line-height:1.3}
.rp-card span{font-size:11.5px;color:var(--muted)}
.rp-card.ok{border-color:#c8efd9;background:#f2fbf6}
.rp-card.ok b{color:#067647}
.rp-card.bad{border-color:#fbd5d1;background:#fef6f5}
.rp-card.bad b{color:#b42318}
.rp-card.warn{border-color:#ffe2b8;background:#fffaf1}
.rp-card.warn b{color:#b25e00}
.rp-line{display:flex;gap:10px;font-size:12.5px;line-height:1.85;align-items:flex-start}
.rp-line .k{flex:0 0 92px;color:var(--muted)}
.rp-line .v{flex:1;min-width:0;word-break:break-all}
.rp-advice{
  background:#fff8ec;border:1px solid #ffe2b8;color:#8a5300;border-radius:10px;
  padding:11px 13px;font-size:12.5px;line-height:1.8;margin-top:12px;
  display:flex;flex-direction:column;gap:5px;
}
.rp-advice b{font-size:13.5px}
.rp-advice code{font-family:var(--mono);font-size:11.5px;background:rgba(15,23,42,.07);padding:1px 5px;border-radius:5px}
.rp-good{background:#eefaf3;border-color:#c8efd9;color:#076a41}

/* ───────── 成员「移出」按钮 ───────── */
.member .mini-btn.kick{background:#fef6f5;color:#b42318;border-color:#fbd5d1}
.member .mini-btn.kick:hover{background:#fdeceb;border-color:#f7c7c2}

/* ───────── 自绘选择框（退出课堂等） ───────── */
.choose-list{display:flex;flex-direction:column;gap:8px;margin:4px 0 6px}
.choose-item{
  display:flex;flex-direction:column;gap:2px;text-align:left;
  border:1px solid var(--line);border-radius:11px;padding:11px 14px;background:#fff;transition:.15s;
}
.choose-item b{font-size:13.5px}
.choose-item span{font-size:11.5px;color:var(--muted);line-height:1.6}
.choose-item:hover{border-color:var(--brand);background:var(--brand-soft)}
.choose-item.danger b{color:#b42318}
.choose-item.danger:hover{border-color:#f7c7c2;background:#fef6f5}

/* ───────── 放大展示二维码（投影用） ───────── */
.qr-big{
  background:#fff;border-radius:20px;padding:22px;box-shadow:var(--shadow-lg);
  display:flex;flex-direction:column;align-items:center;gap:12px;max-width:92vw;
  animation:gateIn .26s cubic-bezier(.2,.8,.3,1) both;
}
.qr-big canvas{display:block;max-width:100%;height:auto;border-radius:6px}
.qr-big-foot{display:flex;flex-direction:column;align-items:center;gap:4px;text-align:center;max-width:100%}
.qr-big-foot b{font-size:15px}
.qr-big-foot span{
  font-family:var(--mono);font-size:11.5px;color:var(--muted);
  word-break:break-all;max-width:70vw;
}
.qr-big-foot .btn{margin-top:6px}

/* ═══════════════════════════════════════════════════
   课堂互动：随机点名 + 出题答题
   ═══════════════════════════════════════════════════ */

/* ───────── 随机点名 ───────── */
.roll-mask{
  position:fixed;inset:0;z-index:120;display:flex;align-items:center;justify-content:center;
  background:rgba(15,23,42,.55);backdrop-filter:blur(3px);animation:fadeIn .18s ease both;
}
.roll-mask.hidden{display:none}
.roll-card{
  background:#fff;border-radius:22px;padding:30px 46px 24px;min-width:min(520px,90vw);
  box-shadow:var(--shadow-lg);display:flex;flex-direction:column;align-items:center;gap:10px;
  animation:gateIn .28s cubic-bezier(.2,.8,.3,1) both;
}
.roll-tag{
  font-size:12px;font-weight:700;letter-spacing:.14em;color:var(--brand);
  background:var(--brand-soft);border-radius:999px;padding:4px 13px;
}
.roll-name{
  font-size:clamp(40px,7vw,68px);font-weight:800;line-height:1.18;letter-spacing:.02em;
  color:var(--brand);min-height:1.2em;transition:transform .12s;
}
.roll-name.landed{animation:rollLand .42s cubic-bezier(.2,1.5,.4,1) both}
.roll-sub{font-size:12.5px;color:var(--muted);text-align:center;min-height:18px}
.roll-acts{display:flex;gap:10px;margin-top:6px}
@keyframes rollLand{0%{transform:scale(1.32)}60%{transform:scale(.97)}100%{transform:scale(1)}}
@keyframes fadeIn{from{opacity:0}to{opacity:1}}

/* ───────── 出题表单 ───────── */
.quiz-form{
  flex:0 0 auto;display:flex;flex-direction:column;gap:8px;
  padding:12px;border-bottom:1px solid var(--line);background:var(--panel-2);
}
.qf-row{display:flex;gap:8px;align-items:flex-end}
.qf-field{display:flex;flex-direction:column;gap:4px;flex:1;min-width:0}
.qf-field span{font-size:11px;color:var(--muted);font-weight:600}
.qf-field select{
  height:34px;padding:0 8px;border-radius:9px;border:1px solid var(--line);
  background:#fff;font-size:12.5px;color:var(--text);outline:none;
}
.qf-stem{
  height:38px;padding:0 11px;border-radius:9px;border:1px solid var(--line);
  background:#fff;font-size:13px;outline:none;
}
.qf-stem:focus,.qo-row input:focus,.qf-field select:focus{border-color:var(--brand);box-shadow:0 0 0 3px var(--brand-soft)}
.quiz-opts{display:flex;flex-direction:column;gap:6px}
.qo-row{display:flex;align-items:center;gap:7px}
.qo-label{
  flex:0 0 22px;height:22px;border-radius:7px;background:var(--brand-soft);color:var(--brand);
  font-size:11.5px;font-weight:700;display:flex;align-items:center;justify-content:center;
}
.qo-row input{
  flex:1;height:33px;padding:0 10px;border-radius:9px;border:1px solid var(--line);
  background:#fff;font-size:12.5px;outline:none;min-width:0;
}
#quizPublish{flex:0 0 auto;height:34px;padding:0 14px}
.qf-hint{font-size:11px;color:var(--muted);line-height:1.6;margin:0}

/* ───────── 当前题目 / 答题卡 / 统计 ───────── */
.quiz-live{flex:1;overflow-y:auto;padding:12px;display:flex;flex-direction:column;gap:10px}
.ql-empty{font-size:12.5px;color:var(--muted);line-height:1.8;text-align:center;padding:22px 10px}
.ql-card{border:1px solid var(--line);border-radius:13px;padding:12px;background:#fff}
.ql-card.closed{background:var(--panel-2)}
.ql-head{display:flex;align-items:center;gap:7px;margin-bottom:8px}
.ql-type{
  font-size:10.5px;font-weight:700;color:#fff;background:var(--brand);
  border-radius:6px;padding:2px 7px;flex:0 0 auto;
}
.ql-type.tf{background:var(--violet)}
.ql-state{font-size:11px;color:var(--muted);margin-left:auto}
.ql-stem{font-size:14px;font-weight:600;line-height:1.6;color:var(--text);margin-bottom:10px;word-break:break-word}
.ql-opts{display:flex;flex-direction:column;gap:7px}
.ql-opt{
  position:relative;display:flex;align-items:center;gap:9px;border:1px solid var(--line);
  border-radius:10px;padding:8px 10px;background:#fff;overflow:hidden;text-align:left;width:100%;
  transition:.15s;font:inherit;color:inherit;
}
button.ql-opt{cursor:pointer}
button.ql-opt:hover{border-color:var(--brand);background:var(--brand-soft)}
.ql-opt.picked{border-color:var(--brand);background:var(--brand-soft);box-shadow:inset 0 0 0 1px var(--brand)}
.ql-opt.right{border-color:var(--green);background:#ecfdf3}
.ql-opt .ql-bar{
  position:absolute;left:0;top:0;bottom:0;background:rgba(47,111,237,.12);
  border-radius:10px 0 0 10px;transition:width .35s cubic-bezier(.2,.8,.3,1);pointer-events:none;
}
.ql-opt.right .ql-bar{background:rgba(18,183,106,.16)}
.ql-key{
  flex:0 0 22px;height:22px;border-radius:7px;background:var(--brand-soft);color:var(--brand);
  font-size:11.5px;font-weight:700;display:flex;align-items:center;justify-content:center;position:relative;
}
.ql-text{flex:1;font-size:12.5px;line-height:1.5;position:relative;word-break:break-word}
.ql-num{font-size:11.5px;color:var(--text-2);font-weight:600;position:relative;flex:0 0 auto}
.ql-check{font-size:11.5px;color:var(--green);font-weight:700;position:relative;flex:0 0 auto}
.ql-status{font-size:11.5px;color:var(--muted);margin-top:9px;display:flex;gap:8px;flex-wrap:wrap;align-items:center}
.ql-acts{display:flex;flex-wrap:wrap;gap:7px;margin-top:10px}
.ql-acts .btn{height:31px;padding:0 12px;font-size:12px}
.ql-tip{
  font-size:11.5px;color:#b54708;background:#fffaeb;border:1px solid #fedf89;
  border-radius:9px;padding:7px 10px;line-height:1.6;
}

/* 角色可见性：.teacher-only 默认 display:none，出题表单是 flex，得单独提权 */
.quiz-form.teacher-only{display:none}
body.is-teacher .quiz-form.teacher-only{display:flex}
.roll-mask.hidden{display:none !important}
.chat-meta .tag.s{background:var(--brand-soft);color:var(--brand)}
.chat-msg.sys .chat-text{background:var(--brand-soft);border:1px solid #d6e2ff;border-radius:10px;white-space:pre-wrap}
.chat-msg.sys .av{background:var(--brand)}
/* 投票统计是多行数据（选项行长短不一），居中会让左边缘参差 → 靠左
   tabular-nums 让「人数 / 百分比」数字等宽对齐；其它系统提示仍居中 */
.chat-msg.sys.quiz-push{justify-content:flex-start}
.chat-msg.sys.quiz-push .chat-text{text-align:left;font-variant-numeric:tabular-nums}

.follow-btn{white-space:nowrap;flex:0 0 auto}

/* ───────── 「只选字母」的题目：选项文字在课件上，学生点字母即可 ───────── */
.ql-opt{flex-wrap:wrap}
.ql-tail{
  margin-left:auto;position:relative;display:flex;align-items:center;gap:8px;
}
.ql-opts.lean{gap:8px}
.ql-opts.lean .ql-opt{
  min-height:54px;gap:13px;padding:8px 13px;border-radius:12px;
}
.ql-opts.lean .ql-key{
  flex:0 0 36px;height:36px;border-radius:11px;
  font-size:19px;font-weight:800;letter-spacing:.02em;
  background:var(--brand-soft);color:var(--brand);
}
button.ql-opt.lean:hover .ql-key{background:#fff}
.ql-opts.lean .ql-opt.picked .ql-key,
.ql-opts.lean .ql-opt.right .ql-key{background:var(--brand);color:#fff}
.ql-opts.lean .ql-opt.right .ql-key{background:var(--green)}
.ql-opts.lean .ql-num{font-size:12px;font-weight:700;color:var(--text-2)}
.ql-opts.lean .ql-check{margin-left:0}

/* ───────── 被告知「就是你」的点名提示 ───────── */
.roll-banner{
  flex:0 0 auto;display:flex;align-items:center;gap:10px;
  padding:9px 14px;font-size:13.5px;font-weight:600;color:#9a3412;
  background:linear-gradient(90deg,#fff7ed,#fffbeb);border-bottom:1px solid #fed7aa;
  animation:bannerIn .3s cubic-bezier(.2,.8,.3,1) both;
}
.roll-banner.hidden{display:none !important}
.rb-ico{font-size:17px;animation:rbPulse 1.5s ease-in-out infinite}
.rb-text{margin-right:auto}
.roll-banner .rb-ok{height:28px;padding:0 12px;font-size:12.5px;background:#fff;border-color:#fed7aa;color:#9a3412}
@keyframes rbPulse{0%,100%{transform:scale(1)}50%{transform:scale(1.28)}}
@keyframes bannerIn{from{opacity:0;transform:translateY(-8px)}to{opacity:1;transform:none}}

.roll-card.is-me{border:2px solid var(--brand);box-shadow:0 0 0 6px rgba(47,111,237,.13),var(--shadow-lg)}
.roll-me{font-size:14.5px;font-weight:700;color:var(--brand);text-align:center}
.roll-me.hidden{display:none !important}

/* ───────── 学生作答：先选中，再点「提交答案」───────── */
.ql-submit{
  display:flex;flex-direction:column;align-items:stretch;gap:7px;
  margin-top:11px;padding-top:11px;border-top:1px dashed var(--line);
}
.ql-submit .btn{height:36px;padding:0 20px;font-size:13.5px;font-weight:600;width:100%}
.ql-submit .btn[disabled]{opacity:.5;cursor:not-allowed}
.qs-hint{font-size:11.5px;color:var(--muted);line-height:1.5;flex:1;min-width:92px}
.ql-opt.pending{border-color:var(--brand);background:var(--brand-soft);box-shadow:inset 0 0 0 1px var(--brand)}
.ql-opt.locked{cursor:default}
button.ql-opt.locked:hover{border-color:var(--line);background:#fff}
button.ql-opt.locked.picked:hover{border-color:var(--brand);background:var(--brand-soft)}
.ql-mark{
  font-size:11.5px;font-weight:700;color:var(--brand);position:relative;flex:0 0 auto;
  background:var(--brand-soft);border-radius:6px;padding:2px 7px;
}
.ql-opts.lean .ql-opt.pending .ql-key{background:var(--brand);color:#fff}