*,*:before,*:after{box-sizing:border-box;margin:0;padding:0}:root{--bg: #0f1117;--bg-subtle: #1a1d27;--bg-muted: #242836;--bg-card: #1e2230;--border: #2d3348;--border-focus: #818cf8;--text: #f1f5f9;--text-secondary: #94a3b8;--text-muted: #64748b;--accent: #818cf8;--accent-hover: #6366f1;--accent-light: rgba(129, 140, 248, .1);--green: #34d399;--green-light: rgba(52, 211, 153, .1);--green-border: rgba(52, 211, 153, .3);--red: #f87171;--red-light: rgba(248, 113, 113, .1);--red-border: rgba(248, 113, 113, .3);--yellow: #fbbf24;--yellow-light: rgba(251, 191, 36, .1);--radius: 12px;--radius-sm: 8px;--sidebar-width: 260px;--header-height: 56px;--shadow-sm: 0 1px 2px rgb(0 0 0 / .18);--shadow: 0 16px 40px rgb(0 0 0 / .28);--transition: .15s ease;color-scheme:dark;font-family:Inter,ui-sans-serif,system-ui,-apple-system,BlinkMacSystemFont,Segoe UI,sans-serif}[data-theme=light]{--bg: #ffffff;--bg-subtle: #f9fafb;--bg-muted: #f3f4f6;--bg-card: #ffffff;--border: #e5e7eb;--border-focus: #6366f1;--text: #111827;--text-secondary: #6b7280;--text-muted: #9ca3af;--accent: #4f46e5;--accent-hover: #4338ca;--accent-light: #eef2ff;--green: #059669;--green-light: #ecfdf5;--green-border: #a7f3d0;--red: #dc2626;--red-light: #fef2f2;--red-border: #fecaca;--yellow: #d97706;--yellow-light: #fffbeb;color-scheme:light}html,body,#root{min-height:100%;background:var(--bg);color:var(--text)}body{min-height:100vh;overflow-x:hidden;-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale}button,input,select,textarea{font:inherit}button,a{touch-action:manipulation}a{color:var(--accent);text-decoration:none}a:hover{color:var(--accent-hover)}h1,h2,h3{letter-spacing:0;line-height:1.15}p{line-height:1.55}.app-shell{display:grid;grid-template-columns:var(--sidebar-width) 1fr;grid-template-rows:var(--header-height) 1fr;min-height:100vh;background:var(--bg)}.sidebar{grid-row:1 / -1;border-right:1px solid var(--border);background:#131722;padding:18px 14px;position:sticky;top:0;height:100vh}.sidebar-brand{display:flex;gap:10px;align-items:center;margin-bottom:22px;min-width:0}.sidebar-brand strong,.sidebar-brand span{display:block}.sidebar-brand strong{font-size:.95rem}.sidebar-brand span{color:var(--text-secondary);font-size:.74rem;margin-top:2px}.sidebar-logo{width:36px;height:36px;flex:0 0 36px;border-radius:var(--radius-sm);display:grid;place-items:center;background:var(--accent-light);color:var(--accent);font-weight:800}.sidebar-nav{display:flex;flex-direction:column;gap:6px}.sidebar-link{display:flex;gap:10px;align-items:center;min-height:42px;padding:10px 12px;border-radius:var(--radius-sm);color:var(--text-secondary);transition:background var(--transition),color var(--transition)}.sidebar-link.active,.sidebar-link:hover{background:var(--accent-light);color:var(--accent)}.sidebar-link-icon{width:18px;text-align:center;flex:0 0 18px}.app-header{grid-column:2;min-width:0;height:var(--header-height);border-bottom:1px solid var(--border);background:#0f1117e6;-webkit-backdrop-filter:blur(16px);backdrop-filter:blur(16px);display:flex;align-items:center;justify-content:space-between;gap:16px;padding:0 24px;position:sticky;top:0;z-index:4}.app-header h1{font-size:1rem}.app-header p{color:var(--text-secondary);font-size:.78rem;margin-top:2px}.header-user{display:flex;gap:12px;align-items:center;color:var(--text-secondary);font-size:.85rem;min-width:0}.header-user span{max-width:240px;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}.app-content{grid-column:2;min-width:0;overflow-y:auto;padding:32px}.page-section,.stats-view{width:min(1180px,100%);animation:slideIn .22s ease-out}.page-header,.stats-header-row,.section-title-row,.table-toolbar{display:flex;align-items:flex-start;justify-content:space-between;gap:16px;margin-bottom:20px}.page-header h2,.stats-header-row h2{font-size:clamp(1.45rem,2vw,2rem);margin-bottom:6px}.page-header p,.text-muted,.stats-empty{color:var(--text-secondary)}.class-detail-meta{display:flex;flex-wrap:wrap;gap:8px 14px}.class-detail-meta span{display:inline-flex;align-items:center}.button-row,.quick-actions,.dialog-actions,.score-pills,.admin-pin-row,.part-review-buttons{display:flex;align-items:center;gap:10px;flex-wrap:wrap}.auth-screen{min-height:100vh;display:grid;place-items:center;padding:24px;background:radial-gradient(circle at top left,rgb(129 140 248 / .16),transparent 34%),linear-gradient(135deg,#0f1117,#161a24 52%,#10131c)}.auth-card{width:min(420px,100%);border:1px solid rgb(255 255 255 / .1);border-radius:var(--radius);background:#1e2230d1;box-shadow:var(--shadow);-webkit-backdrop-filter:blur(18px);backdrop-filter:blur(18px);padding:24px;animation:fadeIn .25s ease-out}.auth-brand{color:var(--accent);font-weight:800;margin-bottom:12px}.auth-card h2{margin-bottom:8px}.auth-subtext,.auth-hint,.auth-footer-link{color:var(--text-secondary);font-size:.9rem}.auth-field,.form-grid{display:grid;gap:10px}.auth-field{margin-top:16px}.auth-footer-link{margin-top:16px;text-align:center}.auth-card .btn-primary{margin-top:10px}.auth-banner{margin:14px 0;border-radius:var(--radius-sm);padding:10px 12px;font-size:.88rem}.auth-banner-warning{background:var(--yellow-light);border:1px solid rgb(251 191 36 / .32);color:var(--yellow)}.btn-primary,.btn-secondary,.btn-link,.override-btn,.review-decision-btn,.part-edit-toggle,.student-select-row{border:0;border-radius:var(--radius-sm);cursor:pointer;transition:background var(--transition),border-color var(--transition),color var(--transition)}.btn-primary,.btn-secondary,.override-btn,.review-decision-btn,.part-edit-toggle{min-height:40px;display:inline-flex;align-items:center;justify-content:center;gap:8px;padding:9px 14px;font-weight:700;white-space:nowrap}.btn-primary{background:var(--accent);color:#0f1117}.btn-primary:hover{background:var(--accent-hover);color:#fff}.btn-primary:disabled,.btn-secondary:disabled{opacity:.55;cursor:not-allowed}.btn-secondary,.override-btn,.part-edit-toggle{border:1px solid var(--border);background:var(--bg-muted);color:var(--text)}.btn-secondary:hover,.override-btn:hover,.part-edit-toggle:hover{border-color:var(--border-focus);color:var(--accent)}.btn-link{background:transparent;color:var(--accent);padding:0}.compact{min-height:34px;padding:7px 10px;font-size:.85rem}.review-decision-btn.correct{background:var(--green-light);color:var(--green);border:1px solid var(--green-border)}.review-decision-btn.incorrect{background:var(--red-light);color:var(--red);border:1px solid var(--red-border)}.review-decision-btn.active,.override-btn.active,.part-edit-toggle.active{outline:2px solid var(--accent);outline-offset:2px}.answer-field,.admin-pin-input,select.answer-field,textarea.answer-field{width:100%;min-height:42px;border:1px solid var(--border);border-radius:var(--radius-sm);background:var(--bg-muted);color:var(--text);padding:10px 12px}.answer-field:focus,.admin-pin-input:focus{outline:none;border-color:var(--border-focus);box-shadow:0 0 0 3px #818cf829}.search-field{max-width:420px;margin-bottom:18px}.field-label,.stats-kpi-label,.part-review-label,.detail-item label{color:var(--text-secondary);font-size:.78rem;font-weight:700;text-transform:uppercase;letter-spacing:0}.checkbox-row,.partial-credit-toggle{display:inline-flex;gap:8px;align-items:center;color:var(--text-secondary)}.key-card,.admin-card,.dashboard-card,.table-panel,.empty-state,.dialog-panel{border:1px solid var(--border);border-radius:var(--radius);background:var(--bg-card);box-shadow:var(--shadow-sm)}.key-card,.admin-card,.dashboard-card,.empty-state,.dialog-panel{padding:18px}.dashboard-grid,.stats-kpi-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(280px,1fr));gap:16px}.stats-kpi-grid{margin-bottom:28px}.dashboard-card{display:flex;flex-direction:column;gap:12px}.dashboard-card.muted{opacity:.68}.card-link{color:inherit;text-decoration:none}.card-link:hover h3{color:var(--accent)}.card-topline,.card-metrics,.stats-activity-row,.grade-row{display:flex;align-items:center;justify-content:space-between;gap:10px}.card-metrics,.stats-activity-meta{color:var(--text-secondary);font-size:.86rem}.badge,.category-badge,.status-badge,.diag-pill,.pill,.overridden-badge,.part-mode-badge,.q-score-badge{display:inline-flex;align-items:center;border-radius:999px;padding:4px 9px;font-size:.75rem;font-weight:800;line-height:1}.badge,.category-badge.quiz{background:var(--accent-light);color:var(--accent)}.category-badge.test{background:var(--yellow-light);color:var(--yellow)}.category-badge.homework{background:var(--green-light);color:var(--green)}.category-badge.exam{background:var(--red-light);color:var(--red)}.status-badge{background:var(--green-light);border:1px solid var(--green-border);color:var(--green)}.status-badge.inline{margin:0}.status-badge.review_pending,.status-badge.draft,.pill.partial{background:var(--yellow-light);color:var(--yellow);border:1px solid rgb(251 191 36 / .3)}.status-badge.finalized,.pill.correct,.diag-ok{background:var(--green-light);color:var(--green);border:1px solid var(--green-border)}.pill.incorrect,.diag-error{background:var(--red-light);color:var(--red);border:1px solid var(--red-border)}.stats-kpi-card{min-height:112px}.stats-kpi-value{margin-top:8px;font-size:2rem;font-weight:850}.stats-kpi-accent{color:var(--accent)}.stats-kpi-good{color:var(--green)}.stats-kpi-warn{color:var(--yellow)}.quick-actions{margin-top:24px}.empty-state{text-align:center;color:var(--text-secondary)}.empty-state h3{color:var(--text);margin-bottom:8px}.table-panel{overflow:hidden}.enroll-cta-row{display:flex;justify-content:center;margin-top:16px}.table-toolbar{padding:16px 18px 0;margin-bottom:10px}.data-table,.stats-table{width:100%;border-collapse:collapse}.data-table th,.data-table td,.stats-table th,.stats-table td{padding:12px 14px;border-bottom:1px solid var(--border);text-align:left;vertical-align:middle}.data-table th,.stats-table th{color:var(--text-secondary);font-size:.76rem;text-transform:uppercase;letter-spacing:0}.data-table tr:hover td,.stats-table tr:hover td{background:#ffffff06}.stats-table-wrap{overflow-x:auto}.tabs{display:inline-flex;border:1px solid var(--border);border-radius:var(--radius-sm);overflow:hidden;margin-bottom:18px;background:var(--bg-muted)}.tabs button{border:0;background:transparent;color:var(--text-secondary);padding:10px 16px;cursor:pointer}.tabs button.active{background:var(--accent-light);color:var(--accent)}.accordion-list{display:grid;gap:12px}summary{cursor:pointer;font-weight:800;margin-bottom:12px}.grade-row{border-top:1px solid var(--border);padding:10px 0}.upload-section,.results-section{display:grid;gap:18px}.drop-zone{min-height:280px;border:1px dashed var(--accent);border-radius:var(--radius);background:#1b2030;display:grid;place-items:center;text-align:center;padding:32px;cursor:pointer;transition:border-color var(--transition),background var(--transition)}.drop-zone:hover{border-color:var(--accent-hover);background:#20263a}.drop-zone-icon{display:block;font-size:2.4rem;margin-bottom:12px}.preview-container{position:relative;width:min(100%,680px)}.preview-image{max-width:100%;max-height:520px;border-radius:var(--radius-sm);border:1px solid var(--border);object-fit:contain}.preview-remove{position:absolute;top:10px;right:10px;width:32px;height:32px;border:0;border-radius:50%;background:var(--red);color:#0f1117;cursor:pointer;font-weight:900}.loading-container{min-height:180px;display:grid;place-items:center;align-content:center;gap:10px;color:var(--text-secondary)}.loading-spinner{width:34px;height:34px;border-radius:50%;border:3px solid var(--border);border-top-color:var(--accent);animation:spin .8s linear infinite}.error-box{border:1px solid var(--red-border);border-radius:var(--radius-sm);background:var(--red-light);color:var(--red);padding:12px 14px;margin:12px 0}.score-card{border:1px solid var(--border);border-radius:var(--radius);background:var(--bg-card);padding:22px;display:flex;gap:22px;align-items:center}.score-ring{width:136px;height:136px;flex:0 0 136px;border-radius:50%;display:grid;place-items:center;background:conic-gradient(var(--grade-color) var(--score-deg),var(--bg-muted) 0)}.score-ring-inner{width:104px;height:104px;border-radius:50%;background:var(--bg-card);display:grid;place-items:center;align-content:center}.score-letter{font-size:2rem;font-weight:900}.score-pct{color:var(--text-secondary);font-size:.88rem}.questions-list{display:grid;gap:14px}.question-card{border:1px solid var(--border);border-left:4px solid var(--red);border-radius:var(--radius);background:var(--bg-card);padding:16px}.question-card.correct{border-left-color:var(--green)}.question-card.overridden{box-shadow:0 0 0 1px #818cf84d}.question-card.blank-answer{border-left-color:var(--yellow)}.question-header{display:flex;align-items:center;gap:10px;margin-bottom:12px}.q-number{flex:0 0 auto;color:var(--accent);font-weight:900}.q-text{flex:1;min-width:0;overflow-wrap:anywhere}.q-status{flex:0 0 auto;font-weight:900;color:var(--text)}.question-details{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:12px}.detail-item{display:grid;gap:8px}.answer-chip-row{display:flex;gap:8px;flex-wrap:wrap}.answer-chip{border-radius:999px;padding:6px 10px;background:var(--bg-muted);color:var(--text);overflow-wrap:anywhere}.answer-chip.blank{background:var(--yellow-light);color:var(--yellow)}.answer-chip.correct{background:var(--green-light);color:var(--green)}.answer-chip.filled{border:1px solid var(--border)}.explanation,.needs-review-banner,.part-mode-helper{grid-column:1 / -1;color:var(--text-secondary);font-size:.9rem}.needs-review-banner{width:100%;border:1px solid rgb(251 191 36 / .3);border-radius:var(--radius-sm);background:var(--yellow-light);color:var(--yellow);padding:10px 12px}.part-review-grid{display:grid;gap:10px;margin-top:12px}.part-review-item{display:flex;justify-content:space-between;gap:12px;align-items:center;border:1px solid var(--border);border-radius:var(--radius-sm);padding:12px;background:var(--bg-muted)}.question-actions,.action-bar{display:flex;gap:10px;flex-wrap:wrap;align-items:center;margin-top:14px}.action-bar .btn-primary{flex:2}.action-bar .btn-secondary{flex:1}.word-bank-box{border:1px solid var(--green-border);border-radius:var(--radius-sm);background:var(--green-light);color:var(--text);padding:12px 14px;display:grid;gap:6px}.step-indicator{display:flex;align-items:center;justify-content:center;gap:0;margin:0 auto 24px}.step-line{width:54px;height:2px;background:var(--border)}.step-line.done{background:var(--accent)}.step-item{min-height:36px;display:inline-flex;align-items:center;gap:8px;color:var(--text-secondary);font-size:.86rem;font-weight:700}.step-item.active{color:var(--accent)}.step-item.done{color:var(--green)}.step-dot{width:28px;height:28px;border-radius:50%;display:grid;place-items:center;border:1px solid var(--border);background:var(--bg-muted)}.step-item.active .step-dot{border-color:var(--accent);background:var(--accent-light)}.step-item.done .step-dot{border-color:var(--green-border);background:var(--green-light)}.grading-session-layout{display:grid;grid-template-columns:260px minmax(0,1fr);gap:24px;width:min(1280px,100%);animation:slideIn .22s ease-out}.student-selector{border:1px solid var(--border);border-radius:var(--radius);background:var(--bg-card);padding:16px;align-self:start;position:sticky;top:calc(var(--header-height) + 24px)}.student-selector h3{margin:14px 0 10px}.student-select-row{width:100%;min-height:40px;display:flex;align-items:center;justify-content:flex-start;background:transparent;color:var(--text-secondary);padding:9px 10px;margin-bottom:6px;text-align:left}.student-select-row.active,.student-select-row:hover{background:var(--accent-light);color:var(--accent)}.grading-workspace{min-width:0}.admin-main{max-width:1100px}.admin-card{margin-bottom:16px}.admin-card p,.registration-meta,.admin-note{color:var(--text-secondary)}.health-chip-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(160px,1fr));gap:10px;margin-top:10px}.health-chip,.diagnostic-row,.switch-row,.admin-empty{border:1px solid var(--border);border-radius:var(--radius-sm);background:var(--bg-muted);padding:10px 12px}.health-chip span{color:var(--text-muted);font-size:.72rem;text-transform:uppercase}.health-chip strong{display:block;margin-top:4px}.health-chip-good{border-color:var(--green-border);background:var(--green-light)}.health-chip-warn{border-color:#fbbf244d;background:var(--yellow-light)}.health-chip-error{border-color:var(--red-border);background:var(--red-light)}.switch-row{display:flex;justify-content:space-between;align-items:center;margin-top:10px}.switch-toggle{width:48px;height:28px;border:0;border-radius:999px;position:relative;cursor:pointer;background:var(--bg-muted)}.switch-toggle.on{background:var(--green)}.switch-toggle.off{background:var(--text-muted)}.switch-knob{position:absolute;width:22px;height:22px;top:3px;left:3px;border-radius:50%;background:#fff;transition:transform var(--transition)}.switch-toggle.on .switch-knob{transform:translate(20px)}.diagnostic-list,.stats-activity-list{display:grid;gap:10px;margin-top:10px}.diagnostic-row{display:flex;flex-wrap:wrap;align-items:center;gap:8px}.diag-meta{color:var(--text-secondary);font-size:.82rem}.admin-json{margin-top:10px;overflow-x:auto;border:1px solid var(--border);border-radius:var(--radius-sm);background:#0b0d12;color:var(--text-secondary);padding:12px}.admin-advanced{margin-top:12px}.admin-back-link{margin-left:auto}.admin-status-badge{margin-top:10px}.switch-label{color:var(--text);font-weight:700}.switch-row.disabled{opacity:.65}.stats-panel{margin-bottom:24px}.stats-activity-card.needs-review{border-color:var(--yellow)}.stats-activity-score{font-weight:900;font-size:1.4rem}.stats-activity-score.excellent{color:var(--green)}.stats-activity-right{text-align:right}.dialog-backdrop{position:fixed;top:0;right:0;bottom:0;left:0;background:#0000008c;display:grid;place-items:center;z-index:40;padding:20px}.dialog-panel{width:min(420px,100%)}.class-enroll-dialog{width:min(560px,100%)}.dialog-divider{height:1px;background:var(--border);margin:4px 0}.dialog-panel p{color:var(--text-secondary);margin:10px 0 18px}.app{min-height:100vh;background:var(--bg)}.header{min-height:var(--header-height);border-bottom:1px solid var(--border);background:var(--bg-subtle);display:flex;align-items:center;gap:10px;padding:0 24px}.logo{width:34px;height:34px;border-radius:var(--radius-sm);display:grid;place-items:center;background:var(--accent-light)}.tagline{color:var(--text-secondary)}.main{width:min(920px,100%);margin:0 auto;padding:32px 20px 64px}@keyframes spin{to{transform:rotate(360deg)}}@keyframes fadeIn{0%{opacity:0;transform:translateY(8px)}to{opacity:1;transform:translateY(0)}}@keyframes slideIn{0%{opacity:0;transform:translateY(10px)}to{opacity:1;transform:translateY(0)}}@media(max-width:900px){.app-shell{grid-template-columns:1fr;grid-template-rows:auto auto 1fr}.sidebar{grid-row:auto;height:auto;position:static;border-right:0;border-bottom:1px solid var(--border)}.sidebar-brand{margin-bottom:12px}.sidebar-nav{flex-direction:row;overflow-x:auto;padding-bottom:4px}.sidebar-link{flex:0 0 auto}.app-header,.app-content{grid-column:1}.app-header{height:auto;min-height:var(--header-height);align-items:flex-start;flex-direction:column;padding:14px 16px}.app-content{padding:22px 16px 48px}.grading-session-layout{grid-template-columns:1fr}.student-selector{position:static}.question-details{grid-template-columns:1fr}}@media(max-width:640px){.page-header,.stats-header-row,.section-title-row,.table-toolbar,.score-card,.stats-activity-row,.part-review-item,.action-bar{flex-direction:column;align-items:stretch}.dashboard-grid,.stats-kpi-grid{grid-template-columns:1fr}.data-table,.stats-table{min-width:640px}.table-panel{overflow-x:auto}.drop-zone{min-height:220px;padding:24px 16px}.score-ring{width:116px;height:116px;flex-basis:116px}.score-ring-inner{width:88px;height:88px}.question-header{flex-wrap:wrap}.q-text{flex-basis:100%}.header .tagline{display:none}.main{padding:24px 16px 48px}}