.teacher-page{max-width:1800px}.classroom-workspace{display:grid;grid-template-columns:230px minmax(460px,1fr) 300px;border:1px solid var(--line);background:white;min-height:680px}.class-schedule{border-right:1px solid var(--line);background:#fbfcfc}.schedule-list{padding:7px}.schedule-item{display:grid;gap:3px;width:100%;text-align:left;border:1px solid transparent;background:transparent;border-radius:3px;padding:10px;color:var(--ink)}.schedule-item:hover{background:#f0f5f5}.schedule-item.active{background:#e9f5f3;border-color:#afd8d3}.schedule-item span,.schedule-item small{font-size:11px;color:var(--muted)}.schedule-item b{font-size:13px}.prep-box{margin:10px;padding:12px;border-top:1px solid var(--line);display:grid;gap:9px}.prep-box>b{font-size:13px}.check{display:flex;align-items:center;gap:6px;color:#768490;font-size:12px}.check i{display:block;width:12px;height:12px;border:1px solid #bac7cf;border-radius:50%}.check.ready{color:#197365}.check.ready i{background:#339a84;border-color:#339a84;box-shadow:inset 0 0 0 3px #fff}.teaching-board{min-width:0;display:flex;flex-direction:column;background:#101c27;color:white}.board-head{height:54px;display:flex;align-items:center;gap:10px;padding:0 16px;border-bottom:1px solid #2f4655}.board-head b{font-size:14px}.board-head span:last-child{font-size:12px;color:#b6c3cc}.board-canvas{min-height:0;flex:1;display:grid;place-items:center;background:#142432}.board-canvas iframe,.board-canvas video{width:100%;height:100%;border:0;background:#101820}.stage-empty{display:grid;gap:8px;justify-items:center;text-align:center;color:#b4c4cf;padding:25px}.stage-empty b{color:white}.stage-empty .btn{color:white;background:#203948;border-color:#496474;margin-top:5px;text-decoration:none}.resource-rail{min-height:72px;border-top:1px solid #2f4655;display:flex;gap:5px;padding:8px;overflow:auto}.rail-item{width:155px;flex:none;display:grid;grid-template-columns:23px auto;grid-template-rows:auto auto;gap:2px 6px;text-align:left;color:#c1cdd4;border:1px solid transparent;background:#1d313e;padding:6px;border-radius:3px}.rail-item:hover{background:#294250}.rail-item.active{border-color:#6bb3a8;background:#294951}.rail-item>span{grid-row:1 / 3;font:11px "DM Mono",monospace;color:#89a3ae;padding-top:3px}.rail-item i{font-style:normal;width:max-content}.rail-item b{font-size:11px;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}.board-controls{height:52px;border-top:1px solid #2f4655;display:flex;align-items:center;padding:0 14px;gap:8px}.board-controls .btn{color:white;background:#203948;border-color:#496474}.board-controls .btn.primary{background:#007f79;border-color:#007f79}.class-guide{border-left:1px solid var(--line);background:white}.guide-section{padding:15px;border-bottom:1px solid var(--line)}.guide-title{display:flex;align-items:center;margin-bottom:9px}.guide-title b{font-size:13px}.guide-title span{font-size:11px;color:var(--muted);margin-left:auto}.guide-section p{margin:0;color:#536571;font-size:13px;white-space:pre-line;line-height:1.7}.assignment-line{padding:8px 0;border-bottom:1px solid #edf0f2;display:grid;gap:2px}.assignment-line b{font-size:12px}.assignment-line span{font-size:11px;color:var(--muted)}.wide-guide{width:100%;margin-top:12px}.teacher-page .page-head{margin-bottom:14px}@media(max-width:1060px){.classroom-workspace{grid-template-columns:200px minmax(420px,1fr) 260px}}@media(max-width:820px){.classroom-workspace{grid-template-columns:200px minmax(460px,1fr) 280px;min-width:940px}.teacher-page{overflow-x:auto}}