:root{font-family:Inter,ui-sans-serif,system-ui,-apple-system,BlinkMacSystemFont,Segoe UI,sans-serif;color:#172033;background:#f5f7fb;color-scheme:light;--teacher-bg: #f4f6fa;--teacher-surface: #ffffff;--teacher-surface-muted: #f8fafc;--teacher-border-soft: #e8edf4;--teacher-text: #172033;--teacher-muted: #667085;--teacher-primary: #1d4ed8;--teacher-primary-soft: #e7efff;--teacher-warning: #b45309;--teacher-warning-soft: #fff7ed;font-synthesis:none;text-rendering:optimizeLegibility;-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale}*{box-sizing:border-box}body{margin:0;min-width:320px;min-height:100vh;background:var(--teacher-bg);overflow-x:hidden}a{color:inherit}#root{min-height:100vh}.ant-layout{background:var(--teacher-bg)}.ant-card{border-radius:8px}.ant-btn{border-radius:6px}.login-page{min-height:100vh;display:flex;align-items:center;justify-content:center;padding:24px;background:#eef3f8}.login-card{width:min(100%,400px);border-radius:8px}.teacher-page-loading{display:grid;min-height:100vh;place-items:center}.teacher-workspace-shell{min-height:100vh}.teacher-workspace-header,.teacher-grade-header{background:var(--teacher-surface);border-bottom:1px solid var(--teacher-border-soft);display:flex;align-items:center;gap:16px;padding:0 max(20px,env(safe-area-inset-right)) 0 max(20px,env(safe-area-inset-left))}.teacher-workspace-header{justify-content:space-between}.teacher-workspace-title.ant-typography{font-size:22px;line-height:1.2;margin:0;text-wrap:balance}.teacher-workspace-content{padding:24px}.teacher-stat-grid{display:grid;gap:12px;grid-template-columns:repeat(3,minmax(0,1fr));margin-bottom:16px}.teacher-stat-card{background:var(--teacher-surface);border:1px solid var(--teacher-border-soft);border-radius:8px;min-height:88px;padding:16px}.teacher-stat-card span{color:var(--teacher-muted);display:block;font-size:13px;margin-bottom:8px}.teacher-stat-card strong{color:var(--teacher-text);display:block;font-size:30px;font-variant-numeric:tabular-nums;line-height:1}.teacher-stat-card--urgent{border-color:#fed7aa;background:var(--teacher-warning-soft)}.teacher-stat-card--warning strong{color:var(--teacher-warning)}.teacher-stat-card--neutral strong{color:var(--teacher-primary)}.teacher-assignment-card.ant-card{border-color:var(--teacher-border-soft);box-shadow:0 8px 24px #1720330a}.teacher-filter-bar{align-items:center;border-bottom:1px solid var(--teacher-border-soft);display:flex;gap:16px;margin:-4px -4px 16px;min-width:0;padding:4px 4px 12px}.teacher-class-filter{min-width:180px}.teacher-subject-tabs{flex:1;min-width:0}.teacher-subject-tabs .ant-tabs-nav{margin:0}.teacher-assignment-table .ant-table-cell{vertical-align:middle}.teacher-grade-shell{height:100vh;min-height:560px;overflow:hidden}.teacher-grade-header{height:56px;justify-content:flex-start}.teacher-grade-title{align-items:baseline;display:flex;gap:8px;min-width:0}.teacher-grade-title span{color:var(--teacher-muted)}.teacher-grade-title strong{display:block;min-width:0;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}.teacher-grade-stats{align-items:center;display:flex;gap:4px;margin-left:auto}.teacher-grade-body{flex:1;min-height:0}.teacher-grade-sidebar{background:var(--teacher-surface-muted)!important;border-right:1px solid var(--teacher-border-soft);overflow:auto}.teacher-grade-canvas{display:flex;flex-direction:column;min-width:0}.teacher-annotate-shell{display:flex;flex:1;min-height:0;overflow:hidden}.teacher-annotate-main{display:flex;flex:1;flex-direction:column;min-width:0}.teacher-grading-toolbar{align-items:center;background:var(--teacher-surface);border-bottom:1px solid var(--teacher-border-soft);display:grid;gap:12px;grid-template-columns:1fr auto auto;min-height:52px;padding:8px 12px}.teacher-tool-button.ant-btn{font-weight:700;height:34px;min-width:34px;padding:0}.teacher-toolbar-action.ant-btn{height:34px}.teacher-page-switcher .ant-tag{font-variant-numeric:tabular-nums;margin:0}.teacher-canvas-viewport{background:#e5e7eb;display:flex;flex:1;justify-content:center;min-height:0;overflow:auto;padding:20px}.teacher-canvas-viewport canvas{box-shadow:0 12px 34px #17203329}.teacher-comment-panel{background:var(--teacher-surface-muted);border-left:1px solid var(--teacher-border-soft);display:flex;flex-direction:column;gap:16px;overflow:auto;padding:16px;width:336px}.teacher-comment-section{background:var(--teacher-surface);border:1px solid var(--teacher-border-soft);border-radius:8px;padding:14px}.teacher-comment-section h3{font-size:14px;line-height:1.2;margin:0 0 10px}.teacher-score-input{width:100%}.teacher-comment-alert{flex:0 0 auto}.teacher-mistake-card{background:var(--teacher-surface);border:1px solid var(--teacher-border-soft);border-radius:8px;padding:10px}.teacher-mistake-list{width:100%}.teacher-mistake-comment{color:var(--teacher-muted);margin-top:4px}.teacher-correction-images{margin-top:10px}.teacher-correction-title{color:var(--teacher-muted);margin-bottom:6px}.teacher-comment-actions{background:var(--teacher-surface-muted);bottom:0;display:flex;justify-content:space-between;margin-top:auto;padding-top:4px;position:sticky}.teacher-student-list{padding:12px}.teacher-student-group+.teacher-student-group{margin-top:16px}.teacher-student-group-title{align-items:center;color:var(--teacher-muted);display:flex;font-size:12px;font-weight:600;justify-content:space-between;margin-bottom:6px;padding:0 4px}.teacher-student-group-body{display:grid;gap:6px}.teacher-student-card{align-items:center;background:transparent;border:1px solid transparent;border-radius:8px;color:var(--teacher-text);cursor:pointer;display:flex;gap:8px;min-height:48px;padding:8px 10px;text-align:left;touch-action:manipulation;width:100%}.teacher-student-card:hover{background:var(--teacher-surface);border-color:var(--teacher-border-soft)}.teacher-student-card:focus-visible{outline:2px solid var(--teacher-primary);outline-offset:2px}.teacher-student-card--active{background:var(--teacher-primary-soft);border-color:#93b4f8}.teacher-student-card--disabled{color:var(--teacher-muted);cursor:not-allowed;opacity:.72}.teacher-student-meta{display:grid;flex:1;min-width:0}.teacher-student-name,.teacher-student-no{overflow:hidden;text-overflow:ellipsis;white-space:nowrap}.teacher-student-name{font-weight:600}.teacher-student-no{color:var(--teacher-muted);font-size:12px;font-variant-numeric:tabular-nums}.teacher-empty-state{color:var(--teacher-muted);display:grid;flex:1;place-items:center}@media (max-width: 900px){.teacher-workspace-content{padding:16px}.teacher-stat-grid{grid-template-columns:1fr}.teacher-grade-header{align-items:stretch;flex-direction:column}.teacher-filter-bar{display:grid}.teacher-grade-header{height:auto;padding-bottom:10px;padding-top:10px}.teacher-grade-stats{margin-left:0}.teacher-grade-sidebar{flex:0 0 220px!important;max-width:220px!important;min-width:220px!important;width:220px!important}.teacher-grading-toolbar{grid-template-columns:1fr}.teacher-comment-panel{width:300px}}