:root{font-family:Inter,"Microsoft YaHei","PingFang SC",sans-serif;color:#20272b;background:#f5f6f7;font-size:14px;line-height:1.6;--green:#18674b;--line:#dce1e5;--muted:#626b73;--red:#b33340}*{box-sizing:border-box;letter-spacing:0}body{margin:0}button,input,textarea,select{font:inherit}button,a{touch-action:manipulation}button{cursor:pointer;border:1px solid var(--line);background:white;border-radius:5px;padding:8px 14px;color:inherit;display:inline-flex;align-items:center;justify-content:center;gap:7px;min-height:38px}button:hover{background:#f0f4f3}button:disabled{opacity:.55;cursor:not-allowed}button.primary{color:white;background:var(--green);border-color:var(--green)}button.primary:hover{background:#12523c}a{color:var(--green)}button svg,.icon svg{width:18px;height:18px;flex:none}.icon{width:38px;padding:8px}.icon:focus-visible,button:focus-visible,a:focus-visible{outline:3px solid #58a0da;outline-offset:3px}input,select,textarea{border:1px solid #b9c3c9;border-radius:4px;padding:10px;width:100%;color:inherit;background:white}input:focus,select:focus,textarea:focus{outline:2px solid #399471;outline-offset:1px}label{display:block;font-weight:600;margin:10px 0 5px}h1,h2,h3,p{margin-top:0}h1{font-size:24px}h2{font-size:19px}h3{font-size:16px}p{margin-bottom:12px}.muted,small{color:var(--muted)}small{font-size:12px}.loading{padding:80px 24px;text-align:center}.topbar{height:60px;display:flex;align-items:center;justify-content:space-between;padding:0 22px;border-bottom:1px solid var(--line);background:white;gap:16px}.brand{display:flex;gap:10px;align-items:center;color:#20272b;text-decoration:none;white-space:nowrap}.brand img{width:30px;height:30px}.brand strong{font-size:19px}.brand span{border-left:1px solid var(--line);padding-left:12px;font-size:14px}.top-actions{display:flex;align-items:center;gap:10px;min-width:0}.badge{font-size:12px;background:#e9eef1;border:1px solid #d9e1e6;padding:2px 8px;border-radius:4px;white-space:nowrap}.banner{padding:8px 22px;background:#fff5d8;color:#735119;border-bottom:1px solid #e9d59e;font-size:13px}.error{color:var(--red);background:#fff1f2;padding:10px 12px;border-radius:4px;overflow-wrap:anywhere}.error:empty{display:none}.entry{max-width:430px;margin:9vh auto;padding:28px 20px}.entry h1{margin-bottom:10px}.entry .primary{width:100%;margin-top:18px}.entry .foot{border-top:1px solid var(--line);margin-top:30px;padding-top:16px;font-size:13px}.entry .logo{width:48px;height:48px;margin-bottom:22px}.entry input{height:46px}.entry .consent{font-size:12px;margin-top:14px}.work{display:grid;grid-template-columns:220px minmax(0,1fr);height:calc(100dvh - 98px);min-height:460px}.sidebar{background:#eef1f3;border-right:1px solid var(--line);padding:22px 14px;display:flex;flex-direction:column;gap:20px;overflow:auto}.sidebar h2{font-size:12px;text-transform:uppercase;color:var(--muted);font-weight:500;padding:0 9px;margin:0 0 10px}.task-list{display:grid;gap:4px}.task-list button{text-align:left;justify-content:flex-start;background:transparent;border-color:transparent;min-height:44px;font-size:14px;padding:8px 10px}.task-list button.active{background:white;border-color:var(--line);color:var(--green);font-weight:600}.task-list button span{min-width:0;overflow-wrap:anywhere}.student-meta{margin-top:auto;border-top:1px solid #d3dbe0;padding:14px 8px 0;font-size:12px}.student-meta strong{display:block;word-break:break-all;color:#374651}.panels{display:grid;grid-template-columns:minmax(0,1fr) minmax(340px,.92fr);min-width:0;min-height:0}.coding{display:flex;flex-direction:column;min-width:0;min-height:0;border-right:1px solid var(--line);background:white}.section-head{height:60px;flex:none;padding:0 20px;display:flex;align-items:center;justify-content:space-between;gap:8px;border-bottom:1px solid var(--line)}.section-head h2{font-size:15px;margin:0}.task-body{padding:20px 22px;border-bottom:1px solid var(--line);max-height:200px;overflow:auto}.task-body h3{margin-bottom:8px}.task-body p{font-size:14px;margin:0}.editor{flex:1;min-height:200px;display:flex;flex-direction:column;background:#202225;color:#e1e5e8}.filebar{height:41px;background:#292c30;color:#e1e5e8;padding:9px 16px;font:13px Consolas,monospace;border-bottom:1px solid #393d41;display:flex;align-items:center;gap:9px}.filebar .language{color:#e0c375}.code-wrap{display:flex;flex:1;min-height:0;overflow:hidden}.line-numbers{width:46px;flex:none;padding:16px 8px;text-align:right;background:#202225;color:#81888f;white-space:pre;font:14px/1.8 Consolas,monospace;overflow:hidden;user-select:none}.code-wrap textarea{border:0;border-radius:0;resize:none;flex:1;min-height:220px;background:#202225;color:#e1e5e8;font:14px/1.8 Consolas,"Microsoft YaHei",monospace;padding:16px 12px;tab-size:4;white-space:pre;overflow:auto}.code-wrap textarea:focus{outline:0}.editor-status{font-size:12px;padding:5px 16px;background:#303438;color:#d4dade;display:flex;justify-content:space-between;gap:8px}.editor-controls{padding:12px 18px;display:flex;justify-content:space-between;gap:10px;align-items:center;border-top:1px solid var(--line)}.editor-controls small{max-width:60%}.chat{display:flex;flex-direction:column;min-height:0;min-width:0;background:#fff}.avatar{width:36px;height:36px;border-radius:6px;display:grid;place-items:center;background:#e4f0ea;color:var(--green);flex:none}.agent{display:flex;align-items:center;gap:10px}.agent small{display:block}.agent strong{font-size:14px}.messages{overflow:auto;flex:1;min-height:180px;padding:24px 22px;scroll-behavior:smooth}.welcome{color:#566169;border-left:3px solid #3e876a;padding:4px 16px;margin:4px 0 28px;font-size:14px}.turn{margin-bottom:24px}.message-label{font-size:12px;color:var(--muted);display:flex;justify-content:space-between;gap:8px;margin-bottom:6px}.message-body{white-space:pre-wrap;overflow-wrap:anywhere;font-size:14px;line-height:1.85}.question{padding:12px 14px;background:#f0f3f6;border-radius:5px;margin-bottom:16px}.answer{padding:0 3px}.turn details{margin:8px 0;font-size:12px}.turn pre{overflow:auto;max-height:230px;white-space:pre;font-size:12px;background:#e4e9ed;padding:10px}.composer{padding:14px 18px;border-top:1px solid var(--line);background:#fafbfc}.composer textarea{min-height:86px;max-height:180px;resize:vertical}.compose-actions{display:flex;justify-content:space-between;align-items:center;gap:10px;margin-top:10px}.check{font-size:13px;display:flex;align-items:center;gap:7px;font-weight:400;margin:0}.check input{width:16px;height:16px}.saved{font-size:12px;color:var(--muted);margin-top:7px;min-height:19px}.mobile-tabs{display:none}#notice{position:fixed;bottom:24px;left:50%;transform:translateX(-50%);background:#202b32;color:#fff;padding:10px 18px;border-radius:5px;z-index:20;max-width:90%;box-shadow:0 3px 16px #0002;pointer-events:none}#notice:empty{display:none}.manage{max-width:1120px;margin:0 auto;padding:32px 22px;overflow:auto}.manage-head{display:flex;justify-content:space-between;align-items:center;gap:16px;margin-bottom:24px}.manage-head h1{margin:0;font-size:24px}.create-form{display:flex;align-items:end;gap:16px;padding:20px 0;border-top:1px solid var(--line);border-bottom:1px solid var(--line);margin-bottom:24px;flex-wrap:wrap}.create-form label{margin:0}.field{min-width:120px}.field select,.field input{margin-top:6px}.field input{max-width:110px}.table-wrap{overflow:auto;border:1px solid var(--line);border-radius:5px}table{width:100%;border-collapse:collapse;background:white;white-space:nowrap;font-size:13px}th,td{text-align:left;padding:12px 14px;border-bottom:1px solid #e5e9ec}th{background:#eef2f4;font-weight:600;color:#48555e}tr:last-child td{border:0}.empty{text-align:center;padding:50px 20px;color:var(--muted)}.generated{margin-bottom:24px;border-left:3px solid var(--green);padding:10px 18px;background:#eaf3ee}.generated .table-wrap{margin-top:12px}.generated p{font-size:13px;margin:0}.status-line{display:flex;gap:10px;flex-wrap:wrap;margin-bottom:14px}.manage .error{margin:15px 0}.nowrap{white-space:nowrap}.teacher-link{font-size:12px;text-decoration:none}.pending{color:var(--muted);padding:10px 0}.count{font-size:14px;color:var(--muted);font-weight:400}.record-code{font-family:Consolas,monospace}.login-page{min-height:100dvh;background:#f6f7f8}.login-page .banner{position:relative}.login-page .topbar{background:transparent}.recover{font-size:13px;padding:16px;color:var(--red)}
.task-body{flex-shrink:0;max-height:260px}.task-body p{white-space:pre-line;line-height:1.8}.task-list button{min-height:48px}
@media(max-width:1100px){.work{grid-template-columns:180px minmax(0,1fr)}.panels{grid-template-columns:minmax(0,1fr) minmax(300px,1fr)}.sidebar{padding:18px 8px}.task-body{padding:16px}.messages{padding:18px 16px}.brand span{display:none}}
@media(max-width:760px){.topbar{height:auto;min-height:56px;padding:10px 14px;flex-wrap:wrap;gap:8px}.brand strong{font-size:17px}.top-actions{gap:5px}.top-actions .student-id{display:none}.banner{padding:7px 14px;font-size:12px}.work{height:calc(100dvh - 93px);min-height:550px;display:flex;flex-direction:column}.sidebar{padding:8px 12px;flex:none;border-right:0;border-bottom:1px solid var(--line);gap:0}.sidebar h2,.student-meta{display:none}.task-list{display:flex;overflow:auto;gap:6px}.task-list button{flex:none;min-height:34px;padding:5px 10px;font-size:12px}.task-list button svg{display:none}.panels{display:block;flex:1;min-height:0;position:relative}.coding,.chat{height:100%;border-right:0}.mobile-tabs{display:flex;background:#fff;border-bottom:1px solid var(--line);flex:none}.mobile-tabs button{flex:1;border-radius:0;border:0;border-bottom:2px solid transparent;background:white;padding:7px;font-size:13px}.mobile-tabs button.active{border-bottom-color:var(--green);color:var(--green)}.panels[data-tab=chat] .coding,.panels[data-tab=code] .chat{display:none}.section-head{height:54px;padding:0 14px}.messages{padding:18px 14px}.composer{padding:10px 12px}.composer textarea{min-height:70px}.task-body{max-height:130px;font-size:13px}.code-wrap textarea{min-height:150px}.editor{min-height:180px}.entry{margin:4vh auto;padding:24px 20px}.manage{padding:22px 14px}.manage-head{align-items:flex-start;flex-direction:column}.manage-head h1{font-size:22px}.create-form{gap:12px}.status-line{font-size:12px}.brand img{width:27px;height:27px}}

.character-panel{display:flex;align-items:center;gap:18px;padding:16px 22px;border-bottom:1px solid var(--line);background:#f6f8f7;flex:none}
.character-panel>img{width:120px;height:120px;object-fit:cover;border-radius:6px;flex:none}
.character-panel strong{font-size:16px}
.character-panel p{margin:6px 0 0;color:var(--muted);font-size:13px;line-height:1.7}
.avatar img{width:36px;height:36px;object-fit:cover;border-radius:6px}
@media(max-width:760px){.character-panel{gap:12px;padding:10px 14px}.character-panel>img{width:72px;height:72px}.character-panel strong{font-size:14px}.character-panel p{font-size:12px}.messages{min-height:130px}}

.coding{overflow:auto}
.coding .section-head,.editor-controls{flex-shrink:0}
.coding .editor{min-height:220px}
.coding .code-wrap textarea{min-height:120px}
.runner{flex:none;border-top:1px solid var(--line);background:#fafbfc;min-width:0}
.run-toolbar{display:flex;align-items:center;gap:10px;padding:8px 14px;min-height:54px}
.run-buttons{display:flex;align-items:center;gap:6px;flex:none}
#run-status{font-size:12px;color:var(--muted);flex:1;min-width:0;overflow-wrap:anywhere}
.stdin-panel{border-top:1px solid var(--line);padding:6px 16px;font-size:12px}
.stdin-panel summary{cursor:pointer;color:#425868}
.stdin-panel label{margin:6px 0;font-weight:400}
#python-stdin{font:13px/1.6 Consolas,"Microsoft YaHei",monospace;resize:vertical;min-height:72px;max-height:150px}
#python-output{margin:0;padding:10px 16px;height:130px;overflow:auto;white-space:pre-wrap;overflow-wrap:anywhere;font:13px/1.6 Consolas,"Microsoft YaHei",monospace;background:#f0f3f6;color:#243239;border-top:1px solid var(--line)}
#python-output.run-error{color:#9e2733}
.editor-controls small{max-width:none}
@media(max-width:760px){.run-toolbar{padding:6px 12px;gap:6px}.coding .editor{min-height:220px}#python-output{height:120px}.runner .icon{width:34px;min-height:34px;padding:6px}}