:root{--csp-blue:#2563eb;--csp-ink:#152b4f;--csp-muted:#6f809a;--csp-line:#e0e7f1;--csp-bg:#f3f6fb}
*{box-sizing:border-box}body{margin:0;background:var(--csp-bg);color:var(--csp-ink);font-family:Inter,-apple-system,BlinkMacSystemFont,"Segoe UI","PingFang SC","Microsoft YaHei",sans-serif}button,input,select,textarea{font:inherit}button,a,input,select,textarea{outline-offset:3px}button{cursor:pointer}a{color:var(--csp-blue);text-decoration:none}button:disabled{cursor:not-allowed;opacity:.45}input,select,textarea{width:100%;border:1px solid #d4ddea;border-radius:8px;padding:10px 12px;background:#fff;color:var(--csp-ink)}input[type=checkbox],input[type=radio]{width:17px;height:17px;accent-color:var(--csp-blue)}textarea{resize:vertical;min-height:88px}label{display:flex;flex-direction:column;gap:7px;font-size:13px;font-weight:600}small,.muted{color:var(--csp-muted)}[hidden]{display:none!important}
.csp-topbar{height:74px;display:flex;align-items:center;gap:22px;padding:0 34px;background:#fff;border-bottom:1px solid var(--csp-line)}.csp-topbar>a:last-child,.csp-topbar>button:last-child{margin-left:auto}.csp-brand{display:flex;align-items:center;gap:11px;font-weight:750;color:var(--csp-ink)}.brand-icon{display:grid;place-items:center;width:39px;height:39px;color:#fff;background:var(--csp-blue);border-radius:12px;font-size:23px}.csp-brand small{font-size:12px;margin-left:8px;font-weight:500}.role-tag{padding:5px 10px;border-radius:6px;background:#edf3ff;color:var(--csp-blue);font-size:12px}.header-button{border:0;background:none;color:var(--csp-muted);font-size:13px}
.teacher-layout{display:grid;grid-template-columns:240px minmax(0,1fr);min-height:calc(100vh - 74px)}.teacher-sidebar{padding:30px 18px;border-right:1px solid var(--csp-line);background:#fff}.sidebar-heading{font-size:13px;font-weight:700;padding:10px 12px;margin-bottom:8px}.nav-button{width:100%;padding:13px 14px;border:0;background:transparent;text-align:left;border-radius:9px;color:var(--csp-muted);margin-bottom:5px;font-size:14px;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}.nav-button:hover,.nav-button.active{background:#edf3ff;color:var(--csp-blue)}.new-exam-button{width:100%;border:1px dashed #a9bfe9;background:#fff;border-radius:9px;color:var(--csp-blue);padding:12px;margin-top:18px}.sidebar-note{font-size:12px;color:#8b9bb2;line-height:1.9;margin:34px 12px}.teacher-main{padding:36px 40px;max-width:1500px;width:100%}.page-heading{display:flex;align-items:center;justify-content:space-between;gap:20px;margin-bottom:26px}.eyebrow{color:var(--csp-blue);font-size:11px;font-weight:700;letter-spacing:1.8px}.page-heading h1{font-size:28px;margin:8px 0;letter-spacing:-.6px}.page-heading p{font-size:14px;color:var(--csp-muted);line-height:1.7;margin:0}.actions{display:flex;align-items:center;flex-wrap:wrap;gap:9px}.button{display:inline-flex;align-items:center;justify-content:center;gap:6px;background:#fff;border:1px solid #d6e0ed;border-radius:8px;padding:10px 15px;color:var(--csp-ink);font-weight:600;font-size:13px}.button:hover{border-color:#a7b9d7;background:#fafcff}.button.primary{background:var(--csp-blue);color:#fff;border-color:var(--csp-blue)}.button.primary:hover{background:#1d4ed8}.button.danger{color:#bc4242;border-color:#efc7c7}.button.small{padding:6px 10px;font-size:12px}.text-button{background:none;border:0;color:var(--csp-blue);padding:4px;font-size:13px}.card{background:#fff;border:1px solid var(--csp-line);border-radius:14px;overflow:hidden;margin-bottom:22px;box-shadow:0 3px 13px #16366303}.card-head{display:flex;justify-content:space-between;align-items:center;gap:12px;padding:20px 24px;border-bottom:1px solid var(--csp-line)}.card-head h2{font-size:16px;margin:0}.card-body{padding:22px 24px}.table-scroll{overflow:auto}table{width:100%;border-collapse:collapse;font-size:13px}th{text-align:left;font-size:12px;color:var(--csp-muted);font-weight:600;background:#f9fbfe;white-space:nowrap}td,th{padding:14px 18px;border-bottom:1px solid #edf1f7}tbody tr:last-child td{border-bottom:0}td code{font-family:ui-monospace,SFMono-Regular,Consolas,monospace;padding:4px 7px;background:#f0f5fd;color:#315c98;border-radius:5px;white-space:nowrap}.empty{padding:44px 25px;text-align:center;color:var(--csp-muted);font-size:14px;line-height:1.8}.badge{display:inline-block;border-radius:5px;font-size:11px;line-height:1.5;padding:4px 8px;background:#f0f3f8;color:#63738c;white-space:nowrap}.badge.blue{background:#edf3ff;color:#2563eb}.badge.green{background:#eaf7f0;color:#218051}.badge.orange{background:#fff4e6;color:#b5751b}.badge.red{background:#ffeded;color:#b84646}.metrics{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:14px;margin-bottom:24px}.metric{background:white;border:1px solid var(--csp-line);border-radius:12px;padding:17px 21px}.metric strong{display:block;font-size:23px;margin-top:8px}.metric span{font-size:12px;color:var(--csp-muted)}.exam-rule{display:flex;flex-wrap:wrap;gap:14px;margin-bottom:24px;font-size:13px;color:var(--csp-muted)}.exam-rule code{color:var(--csp-blue)}.problem-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:16px}.problem-card{border:1px solid var(--csp-line);border-radius:12px;padding:20px}.problem-card h3{font-size:15px;margin:0 0 10px}.problem-card p{font-size:12px;color:var(--csp-muted);line-height:1.8;margin:10px 0}.notice{border-radius:9px;background:#edf3ff;color:#416290;font-size:13px;line-height:1.8;padding:13px 16px;margin-bottom:18px}.notice.warning{background:#fff4e6;color:#9d6b26}.error-banner{background:#fff0f0;color:#a84343;padding:14px;border-radius:8px;margin:15px 0}.loading{padding:50px;color:var(--csp-muted);text-align:center}
dialog{border:1px solid var(--csp-line);border-radius:16px;padding:0;max-width:880px;width:calc(100% - 36px);max-height:88vh;box-shadow:0 25px 90px #10234533;color:var(--csp-ink)}dialog::backdrop{background:#11294c66;backdrop-filter:blur(2px)}.dialog-head{display:flex;align-items:center;justify-content:space-between;padding:21px 26px;border-bottom:1px solid var(--csp-line)}.dialog-head h2{font-size:19px;margin:0}.dialog-close{border:0;background:#f1f4f9;width:30px;height:30px;border-radius:50%;font-size:18px;color:var(--csp-muted)}.dialog-body{padding:24px 26px}.dialog-footer{display:flex;justify-content:flex-end;gap:10px;padding:18px 26px;border-top:1px solid var(--csp-line);background:#fafcff;position:sticky;bottom:0}.form-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:16px;margin-bottom:20px}.form-grid .span-2{grid-column:span 2}.task-form{padding:18px;border:1px solid var(--csp-line);border-radius:10px;margin:14px 0}.task-form h3{margin:0;font-size:14px}.task-form .form-grid{margin-top:15px;grid-template-columns:repeat(3,minmax(0,1fr));gap:12px}.form-section{font-size:15px;margin:26px 0 12px}.student-picks{max-height:240px;overflow:auto;border:1px solid var(--csp-line);border-radius:8px}.student-pick{display:flex;align-items:center;gap:12px;padding:10px 14px;border-bottom:1px solid #edf1f7;font-size:13px}.student-pick input[type=text]{margin-left:auto;width:160px;padding:7px}.student-pick span small{display:block;font-weight:400}.form-error{font-size:13px;color:#bd4242;line-height:1.6}.csp-toast{position:fixed;bottom:26px;left:50%;transform:translate(-50%,15px);background:#193557;color:#fff;border-radius:9px;padding:12px 20px;z-index:20;max-width:90vw;opacity:0;pointer-events:none;transition:.18s;font-size:13px}.csp-toast.show{opacity:1;transform:translate(-50%,0)}
.join-card{background:white;border:1px solid var(--csp-line);border-radius:20px;width:440px;max-width:calc(100% - 32px);margin:60px auto;padding:36px 38px;box-shadow:0 20px 70px #143b7310}.join-card h1{font-size:34px;line-height:1.3;letter-spacing:-1px;margin:15px 0}.join-card h1 span{color:var(--csp-blue)}.join-card p{font-size:13px;line-height:1.8;color:var(--csp-muted)}.join-card label{margin-top:18px}.join-card .button{width:100%;margin-top:25px;padding:13px}.join-card>small{display:block;line-height:1.7;font-size:11px}.desktop-main{padding:26px 32px;max-width:1660px;margin:auto}.desktop-heading{display:flex;align-items:center;justify-content:space-between;gap:16px;margin-bottom:20px}.desktop-heading h1{font-size:22px;margin:0 0 7px}.desktop-heading p{font-size:12px;color:var(--csp-muted);margin:0}.clock{font-family:ui-monospace,SFMono-Regular,monospace;font-size:23px;letter-spacing:1px;font-weight:650}.clock-label{font-size:11px;color:var(--csp-muted);text-align:right;margin-bottom:4px}.desktop-window{background:#fff;border:1px solid #ccdaed;border-radius:13px;overflow:hidden;box-shadow:0 12px 35px #163c7410}.window-title{display:flex;align-items:center;justify-content:space-between;background:#eff4fc;padding:13px 20px;font-size:13px;font-weight:650}.toolbar{display:flex;align-items:center;flex-wrap:wrap;gap:8px;padding:12px 16px;border-bottom:1px solid var(--csp-line)}.toolbar .button{font-size:12px;padding:8px 11px}.toolbar-end{margin-left:auto}.file-layout{display:grid;grid-template-columns:230px minmax(280px,1fr) minmax(260px,.75fr);min-height:520px}.file-tree{padding:18px 10px;border-right:1px solid var(--csp-line);overflow:auto;max-height:600px;background:#fbfcff}.tree-label{font-size:12px;font-weight:600;margin:0 12px 13px;color:var(--csp-muted)}.tree-row{display:flex;gap:7px;align-items:center;white-space:nowrap;width:100%;padding:9px 10px;border:0;background:transparent;border-radius:6px;text-align:left;font-size:12px;color:#536c8d}.tree-row.active{background:#e4eeff;color:var(--csp-blue);font-weight:650}.folder-icon{color:#e8aa34;font-size:17px}.file-panel{min-width:0;padding:16px}.path-bar{display:flex;align-items:center;gap:8px;border:1px solid #dce5f1;border-radius:8px;padding:9px 12px;margin-bottom:13px;color:#5276a7;font-size:12px;word-break:break-all}.drop-zone{border:1px dashed #a4bde5;border-radius:9px;background:#f8fbff;padding:23px 12px;text-align:center;font-size:13px;color:var(--csp-blue);margin-bottom:17px}.drop-zone small{display:block;color:#8a9ab1;margin-top:6px;font-size:11px}.drop-zone.dragover{background:#e7f0ff;border-color:var(--csp-blue)}.files-table th,.files-table td{padding:12px 8px}.files-table tbody tr{cursor:pointer}.files-table tbody tr:hover{background:#f5f8fe}.files-table tr.selected{background:#edf3ff}.filename{display:flex;gap:8px;align-items:center;max-width:240px;overflow-wrap:anywhere}.file-icon{display:inline-grid;place-items:center;width:23px;height:26px;border-radius:4px;background:#efebff;color:#795adb;font-size:9px;font-weight:700;flex-shrink:0}.preview-panel{border-left:1px solid var(--csp-line);padding:18px;min-width:0;background:#fcfdff}.preview-title{display:flex;justify-content:space-between;font-size:13px;font-weight:600;margin-bottom:14px}.code-preview{background:#fff;border:1px solid var(--csp-line);border-radius:8px;white-space:pre;overflow:auto;padding:15px;font:12px/1.8 ui-monospace,SFMono-Regular,Consolas,monospace;max-height:480px;min-height:420px;margin:0;color:#34537b}.preview-placeholder{display:grid;place-items:center;min-height:420px;color:#91a1b7;font-size:12px;border:1px dashed var(--csp-line);border-radius:8px;text-align:center;line-height:1.8}.status-bar{display:flex;align-items:center;justify-content:space-between;gap:10px;background:#f8faff;border-top:1px solid var(--csp-line);padding:11px 17px;font-size:11px;color:var(--csp-muted)}.task-strip{display:flex;flex-wrap:wrap;gap:10px;margin:20px 0}.task-chip{border:1px solid var(--csp-line);background:#fff;border-radius:8px;text-align:left;padding:12px 17px;font-size:12px}.task-chip strong{display:block;font-size:13px;margin-bottom:5px}.result-score{color:var(--csp-blue);font-size:28px;font-weight:750}.sample-grid{display:grid;grid-template-columns:1fr 1fr;gap:15px}.sample-grid pre{white-space:pre-wrap;font-size:12px;line-height:1.7;max-height:240px;overflow:auto;background:#f5f8fd;padding:15px;border-radius:7px}.file-path-list{max-height:300px;overflow:auto;font-size:12px}.file-path-list button{display:block;text-align:left;width:100%;padding:9px 6px;background:#fff;border:0;border-bottom:1px solid #edf1f7;color:var(--csp-blue);overflow-wrap:anywhere}.detail-pre{white-space:pre-wrap;background:#f6f8fc;padding:18px;border-radius:8px;font:12px/1.8 ui-monospace,SFMono-Regular,monospace;max-height:360px;overflow:auto}.cell-input{min-width:85px;padding:7px}.no-wrap{white-space:nowrap}
@media(max-width:1100px){.teacher-main{padding:28px 22px}.teacher-layout{grid-template-columns:200px minmax(0,1fr)}.file-layout{grid-template-columns:190px minmax(0,1fr)}.preview-panel{grid-column:span 2;border-left:0;border-top:1px solid var(--csp-line)}.code-preview,.preview-placeholder{min-height:180px;max-height:280px}.metrics{grid-template-columns:repeat(2,1fr)}}
@media(max-width:700px){.csp-topbar{padding:0 16px;height:64px;gap:12px}.csp-brand small{display:none}.csp-topbar>a:last-child{font-size:12px}.teacher-layout{display:block}.teacher-sidebar{padding:12px;display:flex;align-items:center;gap:8px;flex-wrap:wrap}.sidebar-heading,.sidebar-note{display:none}#examList{display:flex;overflow:auto;max-width:100%}.nav-button{width:auto;margin:0}.new-exam-button{width:auto;margin:0}.teacher-main,.desktop-main{padding:20px 14px}.page-heading{align-items:flex-start;flex-direction:column}.page-heading h1{font-size:25px}.problem-grid{grid-template-columns:1fr}.card-head,.card-body{padding:17px}.file-layout{display:block;min-height:0}.file-tree{max-height:180px;border-right:0;border-bottom:1px solid var(--csp-line)}.file-panel{padding:12px}.preview-panel{padding:14px}.form-grid,.task-form .form-grid{grid-template-columns:1fr}.form-grid .span-2{grid-column:auto}.dialog-body{padding:18px}.desktop-heading{align-items:flex-start}.desktop-heading h1{font-size:18px}.sample-grid{grid-template-columns:1fr}.student-pick input[type=text]{width:120px}.toolbar-end{margin-left:0}.status-bar{flex-wrap:wrap}}

.csp-topbar .module-nav{margin-left:auto;gap:14px;font-size:13px}.csp-topbar .module-nav a{padding:7px 9px}.csp-topbar .module-nav a.active{background:#edf3ff;color:var(--csp-blue)}
@media(max-width:900px){.csp-topbar .module-nav a:not(.active){display:none}}
@media(max-width:500px){.csp-topbar .module-nav{display:none}}

[draggable="true"]{cursor:grab}[draggable="true"]:active{cursor:grabbing}.move-dragging{opacity:.45}.move-dragover{background:#e3eeff!important;outline:2px solid #2563eb;outline-offset:-2px;border-radius:6px}

.data-upload{padding:8px 0}.upload-progress-label{display:flex;justify-content:space-between;gap:16px;align-items:center;margin:20px 0 12px}.upload-progress-label strong{color:var(--csp-blue);font-variant-numeric:tabular-nums}.data-upload progress{display:block;width:100%;height:16px;border:0;border-radius:8px;overflow:hidden;accent-color:var(--csp-blue)}.data-upload progress::-webkit-progress-bar{background:#e8eef8;border-radius:8px}.data-upload progress::-webkit-progress-value{background:var(--csp-blue);border-radius:8px}.data-upload progress::-moz-progress-bar{background:var(--csp-blue);border-radius:8px}