:root{color-scheme:light;--blue:#145af5;--blue-hover:#1048cb;--tint:#eaf0ff;--ink:#1d2636;--muted:#626e80;--border:#e0e5ed;--surface:#f5f7fa;--paper:#fff;--red:#b42332;--radius:16px;font-family:-apple-system,BlinkMacSystemFont,"SF Pro Text","PingFang SC","Microsoft YaHei",sans-serif;color:var(--ink);background:var(--surface)}
*{box-sizing:border-box}body{margin:0;font-size:15px;line-height:1.6}a{color:var(--blue);text-decoration:none}button,a{touch-action:manipulation}button{font:inherit;cursor:pointer;border:1px solid var(--border);border-radius:10px;background:white;color:var(--ink);padding:9px 16px;min-height:44px}a,button{transition:background .16s,color .16s,box-shadow .16s}button:hover{background:var(--tint)}button:active,a:active{filter:brightness(.96)}:focus-visible{outline:3px solid var(--blue);outline-offset:4px}svg{width:20px;height:20px;fill:none;stroke:currentColor;stroke-width:1.7;stroke-linecap:round;stroke-linejoin:round;flex-shrink:0}h1,h2,p{margin:0}.device{display:grid;grid-template-columns:232px minmax(0,1fr);min-height:100dvh}.sidebar{display:flex;flex-direction:column;background:#fafbfe;border-right:1px solid var(--border);padding:38px 20px 24px;gap:8px}.brand{display:flex;align-items:center;min-height:44px;margin:0 12px 42px;width:max-content}.brand img{display:block;width:156px;height:auto}.sidebar-title{font-size:12px;font-weight:600;letter-spacing:.08em;color:var(--muted);padding:0 16px 8px}.sidebar nav{display:grid;gap:8px}.sidebar nav a{display:flex;gap:12px;align-items:center;min-height:48px;border-radius:11px;padding:12px 16px;color:#4a586c;font-size:14px}.sidebar nav a:hover{background:#eef2f9}.sidebar nav a[aria-current=page]{background:var(--tint);color:var(--blue);font-weight:600}.sidebar-bottom{margin-top:auto;display:flex;gap:12px;align-items:center;padding:22px 8px 0;border-top:1px solid var(--border)}.sidebar-bottom img{border-radius:9px}.sidebar-bottom strong{display:block;font-size:13px;font-weight:600}.sidebar-bottom span{display:block;font-size:12px;color:var(--muted);margin-top:2px}.workspace{display:flex;flex-direction:column;min-width:0}.toolbar{min-height:84px;padding:18px 44px;display:flex;justify-content:space-between;align-items:center;gap:16px;border-bottom:1px solid var(--border);background:#ffffffb3}.breadcrumb{display:flex;align-items:center;gap:14px;font-size:13px;color:var(--muted)}.breadcrumb strong{font-weight:500;color:var(--ink)}.save{display:flex;align-items:center;gap:8px;color:var(--muted);font-size:12px;white-space:nowrap}.save::before{content:"";width:6px;height:6px;border-radius:50%;background:#8290a5}.save[data-state=connected]::before{background:#25865d}.save[data-state=error]::before{background:var(--red)}.main{padding:42px 44px 32px;width:100%;max-width:1380px;margin:0 auto;min-width:0;flex:1}.main:focus{outline:none}.heading{display:flex;justify-content:space-between;gap:24px;align-items:center;margin-bottom:32px}.heading h1{font-size:30px;letter-spacing:-.8px;font-weight:650;line-height:1.35}.heading p{margin-top:8px;color:var(--muted);font-size:13px}.segmented{display:flex;background:#e8ecf3;border:1px solid #e2e7ef;padding:4px;border-radius:12px;flex-shrink:0;gap:2px}.segmented button{background:transparent;border:0;font-size:13px;padding:8px 16px;min-height:40px}.segmented button[aria-pressed=true]{background:white;box-shadow:0 2px 5px #1831510d;color:var(--blue);font-weight:600}.assignment{display:flex;align-items:center;gap:20px;border:1px solid var(--border);border-radius:var(--radius);background:white;padding:26px;margin-bottom:16px;box-shadow:0 3px 10px #23395803}.subject-badge{display:grid;place-items:center;flex-shrink:0;width:58px;height:58px;border-radius:16px;background:var(--tint);font:italic 27px Georgia,serif;color:var(--blue)}.assignment-body{flex:1;min-width:0}.assignment h2{font-size:19px;font-weight:650}.assignment p{color:var(--muted);font-size:13px;margin-top:5px}.assignment .assignment-date{font-size:12px;color:var(--muted);margin-top:9px}.assignment a{display:inline-flex;gap:12px;align-items:center;justify-content:center;min-height:44px;border-radius:10px;padding:10px 19px;background:var(--blue);color:#fff;white-space:nowrap;font-size:14px;font-weight:500;box-shadow:0 3px 6px #145af515}.assignment a:hover{background:var(--blue-hover)}.assignment a svg{width:16px}.status-label{color:#5a677b;background:#f0f3f8;font-size:12px;border-radius:7px;padding:5px 10px;white-space:nowrap}.empty{padding:64px 28px;text-align:center;background:white;border:1px solid var(--border);border-radius:var(--radius);color:var(--muted)}.empty svg{width:34px;height:34px;display:block;margin:0 auto 16px;color:#8998b0}.empty h2{font-size:18px;color:var(--ink);margin-bottom:8px}.empty p{font-size:14px}.empty button{margin-top:20px}.upcoming{margin-top:36px}.upcoming h2{font-size:15px;font-weight:600;margin-bottom:16px}.preview-head{display:flex;align-items:center;gap:18px;margin-bottom:24px}.preview-head h1{font-size:21px;font-weight:650}.preview-head>span{font-size:12px;color:var(--muted);margin-left:auto}.back-link{display:inline-flex;align-items:center;justify-content:center;gap:7px;min-height:44px;padding:8px 12px;border:1px solid var(--border);background:white;border-radius:10px;font-size:13px;color:var(--muted)}.back-link svg{width:16px}.question-navigation{display:flex;gap:10px;align-items:center;margin:0 0 24px}.question-navigation a{display:grid;place-items:center;min-width:44px;min-height:44px;border:1px solid var(--border);border-radius:10px;background:white;font-size:14px;color:#5a6880}.question-navigation a[aria-current=step]{background:var(--blue);border-color:var(--blue);color:white;font-weight:600;box-shadow:0 3px 8px #145af524}.question-navigation span{margin-left:auto;color:var(--muted);font-size:12px}.question-split{display:grid;grid-template-columns:minmax(0,1.12fr) minmax(0,1fr);gap:24px;align-items:stretch}.question-card,.response-card{background:white;border:1px solid var(--border);border-radius:var(--radius);padding:28px;min-width:0;min-height:390px;display:flex;flex-direction:column}.question-card h2,.response-card h2{font-size:15px;font-weight:600;margin:0 0 26px;display:flex;align-items:center;justify-content:space-between;gap:12px}.preview-note{color:var(--muted);font-size:12px;font-weight:400;line-height:1.65}.question-text{font-size:20px;line-height:1.9;overflow-wrap:anywhere;color:#202b3b}.question-text p{margin:0 0 18px}.question-text img{display:block;max-width:100%;max-height:300px;object-fit:contain;margin:24px auto}.source{color:var(--muted);font-size:11px;line-height:1.8;margin-top:auto;padding-top:32px;overflow-wrap:anywhere}.option-row{display:flex;align-items:center;gap:16px;padding:14px 16px;border:1px solid #dbe2ec;border-radius:11px;margin:0 0 12px;font-size:18px;min-height:58px}.option-row>strong{display:grid;place-items:center;border:1px solid #dbe2ec;background:#f8fafd;border-radius:7px;width:29px;height:29px;flex-shrink:0;color:#5c6980;font-size:12px;font-weight:500}.option-row p{margin:0}.option-row>div{min-width:0;overflow:auto}.working-note{margin-top:24px;padding:18px;border:1px solid #dce6fa;border-radius:12px;background:#f6f9ff;font-size:13px}.working-note strong{display:flex;align-items:center;gap:8px;font-weight:600;margin-bottom:7px}.working-note strong svg{width:17px;color:var(--blue)}.working-note p{color:var(--muted);font-size:12px;line-height:1.7}.response-card>.preview-note{margin-top:18px}.answer-placeholder{background:#f8fafd;border:1px dashed #aebcd0;border-radius:11px;padding:22px;color:var(--muted);font-size:14px}.question-footer{display:flex;justify-content:space-between;gap:20px;margin-top:24px}.question-footer a{min-height:44px;display:inline-flex;align-items:center;gap:10px;padding:10px 18px;border:1px solid var(--border);border-radius:10px;background:white;font-size:14px}.question-footer a:last-child{background:var(--blue);color:white;border-color:var(--blue)}.phase-note{display:flex;justify-content:center;gap:12px;color:var(--muted);font-size:11px;padding:22px 20px max(24px,env(safe-area-inset-bottom));text-align:center}.phase-note>span{font-weight:700;letter-spacing:-.3px}.landscape-hint{display:none}.error{color:var(--red)}.table-scroll,.katex-display{overflow-x:auto;overflow-y:hidden}.table-scroll table{border-collapse:collapse}.table-scroll td{padding:8px;border:1px solid var(--border)}.katex{font-size:1.1em}.skip-link{position:fixed;top:-80px;left:20px;z-index:20;padding:12px;background:#fff;border:2px solid var(--blue);border-radius:10px}.skip-link:focus{top:10px}
@media(min-width:1800px){.device{grid-template-columns:264px 1fr}.sidebar{padding-inline:28px}.main{padding-top:54px}}
@media(max-width:1100px){.device{grid-template-columns:192px minmax(0,1fr)}.sidebar{padding:30px 14px 20px}.brand{margin:0 8px 36px}.brand img{width:144px}.toolbar{padding:18px 28px}.main{padding:32px 28px}.question-split{gap:16px}.question-card,.response-card{padding:22px}.assignment{gap:16px;padding:22px}.status-label{display:none}.heading{flex-wrap:wrap}}
@media(orientation:portrait) and (min-width:761px){.landscape-hint{display:block;background:var(--tint);border-radius:10px;padding:12px;margin:0 0 20px;color:#305da4;font-size:13px}}
@media(max-width:760px){.device{grid-template-columns:1fr}.sidebar{padding:18px max(18px,env(safe-area-inset-right)) 12px max(18px,env(safe-area-inset-left));border-right:0;border-bottom:1px solid var(--border);gap:16px}.brand{margin:0}.brand img{width:144px}.sidebar-title,.sidebar-bottom{display:none}.sidebar nav{display:flex;gap:8px}.sidebar nav a{flex:1;justify-content:center;min-height:44px;padding:10px;font-size:13px}.toolbar{min-height:64px;padding:14px 20px}.breadcrumb{font-size:12px;gap:10px}.main{padding:28px 20px}.heading{gap:20px;margin-bottom:24px}.heading h1{font-size:26px}.segmented{width:100%}.segmented button{flex:1}.assignment{flex-wrap:wrap;gap:16px;padding:20px}.subject-badge{width:48px;height:48px;border-radius:12px}.assignment-body{min-width:170px}.assignment a{width:100%}.assignment p{font-size:12px}.question-split{grid-template-columns:1fr}.question-card,.response-card{min-height:0;padding:22px}.preview-head{flex-wrap:wrap;gap:12px}.preview-head h1{font-size:19px}.preview-head>span{width:100%;margin:0}.question-navigation{flex-wrap:wrap}.question-navigation span{font-size:11px}.question-text{font-size:18px}.source{padding-top:24px}.phase-note{flex-wrap:wrap;gap:6px;padding-top:12px}.question-footer a{padding:10px 14px}.save{font-size:11px}}
@media(prefers-reduced-motion:reduce){*,*::before,*::after{transition:none!important;scroll-behavior:auto!important}}
.primary{background:var(--blue);border-color:var(--blue);color:white}.primary:hover{background:var(--blue-hover)}button:disabled{opacity:.55;cursor:wait}.toolbar-actions{display:flex;gap:18px;align-items:center}.toolbar-actions button{font-size:12px}.signed-out .sidebar{display:none}.signed-out .device{grid-template-columns:1fr}.signed-out .toolbar{display:none}.signed-out .main{display:grid;place-items:center;min-height:85dvh}.signed-out .phase-note{display:none}.login-panel{background:white;border:1px solid var(--border);border-radius:24px;padding:40px;width:min(100%,440px);box-shadow:0 16px 48px #18315108}.login-panel>img{display:block;margin-bottom:36px;height:auto}.login-panel h1{font-size:28px;letter-spacing:-.6px}.login-panel>p{color:var(--muted);margin-top:8px}.login-panel form{display:grid;gap:10px;margin-top:28px}.login-panel label{font-size:14px;font-weight:600}.login-panel input,textarea{font:inherit;font-size:16px;padding:13px 14px;border:1px solid #c7d1e0;border-radius:10px;min-height:48px;width:100%;color:var(--ink);background:#fff}.login-panel input{margin-bottom:10px}.password-field{position:relative}.password-field input{padding-right:72px}.password-field button{position:absolute;right:5px;top:3px;border:0;font-size:13px}.login-panel .login-note{font-size:12px;margin-top:24px}.login-panel .primary{margin-top:10px}.answers{border:0;margin:0;padding:0;min-width:0}.option-row{cursor:pointer}.option-row:has(input:checked){background:var(--tint);border-color:var(--blue)}.option-row input{accent-color:var(--blue);width:18px;height:18px;flex-shrink:0}.option-row>strong{border:0;background:transparent;width:20px}.option-row:focus-within{outline:2px solid var(--blue);outline-offset:2px}.question-navigation button[aria-current=step]{background:var(--blue);color:white;border-color:var(--blue)}.working-buttons{display:flex;gap:10px;flex-wrap:wrap;margin:12px 0}.working-buttons button{color:var(--blue);border-color:#c2d3fa}.required{font-size:11px;margin-left:auto;color:#98541a;background:#fff2df;border-radius:5px;padding:2px 7px}.response-card>label{font-size:13px;margin-bottom:10px}.response-card textarea{resize:vertical;min-height:110px}.response-card .error{margin-top:14px;font-size:13px}.save-retry{align-self:flex-start;margin-top:18px;font-size:13px}.saving-explanation{text-align:right;margin-top:18px}.working-image{display:flex;align-items:center;gap:12px;padding-top:12px}.working-image>a{flex:1;min-width:0}.working-image img{display:block;max-width:100%;max-height:160px;border:1px solid var(--border);border-radius:8px;background:white}.working-image button{font-size:12px}.sr-only{position:absolute;width:1px;height:1px;clip-path:inset(50%);overflow:hidden;white-space:nowrap}dialog{padding:24px;border:1px solid var(--border);border-radius:18px;width:min(94vw,1100px);max-height:94dvh;overflow:auto;color:var(--ink);box-shadow:0 24px 90px #15263d40}dialog::backdrop{background:#18243a66;backdrop-filter:blur(4px)}.ink-head{display:flex;justify-content:space-between;align-items:center}.ink-head h2{font-size:20px}dialog>p{font-size:13px;color:var(--muted);margin:10px 0}.ink-tools{display:flex;gap:10px;align-items:center;flex-wrap:wrap;margin:14px 0}.ink-tools label{display:flex;gap:8px;align-items:center;min-height:44px;margin-left:auto}.canvas-wrap{background:white;border:1px solid #c7d1e0;border-radius:12px;overflow:hidden}canvas{display:block;width:100%;height:auto;touch-action:none;user-select:none;-webkit-user-select:none}dialog>.primary{display:block;margin-left:auto;margin-top:16px}#ink-error{color:var(--red)}@media(max-width:760px){.login-panel{padding:28px}.toolbar{flex-wrap:wrap}.toolbar-actions{gap:8px;margin-left:auto}.question-navigation button{padding:8px 12px}.saving-explanation{text-align:left}dialog{padding:16px}.ink-tools label{font-size:12px;margin-left:0}}
.grading-progress{background:white;border:1px solid var(--border);border-radius:18px;padding:48px 24px;text-align:center}.grading-progress h2{font-size:22px;margin:18px 0 10px}.grading-progress p{margin:12px 0;color:var(--muted)}.grading-progress progress{width:min(100%,360px);height:8px;accent-color:var(--blue)}.spinner{display:inline-block;width:32px;height:32px;border:3px solid var(--tint);border-top-color:var(--blue);border-radius:50%;animation:spin 1s linear infinite}@keyframes spin{to{transform:rotate(360deg)}}.grading-summary{display:flex;align-items:center;justify-content:space-between;gap:20px;background:white;border:1px solid var(--border);border-radius:16px;padding:24px;margin-bottom:12px}.grading-summary h2{font-size:21px}.grading-summary p{font-size:13px;color:var(--muted);margin-top:6px}.grade-counts{display:flex;gap:24px}.grade-counts span{font-size:13px;color:var(--muted)}.grade-counts strong{display:block;font-size:26px;color:var(--ink)}.result-nav{display:flex;flex-wrap:wrap;gap:10px;margin:26px 0}.graded-question{background:white;border:1px solid var(--border);border-radius:16px;padding:26px;margin:20px 0;scroll-margin-top:20px}.graded-question>header{display:flex;gap:12px;align-items:center;justify-content:space-between;margin-bottom:24px}.graded-question h2{font-size:18px}.graded-question h2 .preview-note{margin-left:12px}.graded-split{display:grid;grid-template-columns:minmax(0,1fr) minmax(0,1fr);gap:32px}.graded-split>section{min-width:0}.graded-split .question-text{font-size:17px}.graded-question h3{font-size:14px;margin:18px 0 8px}.submitted-answer{padding:12px 16px;background:var(--surface);border-radius:10px;overflow-wrap:anywhere}.feedback{border-left:1px solid var(--border);padding-left:28px;font-size:14px;overflow-wrap:anywhere}.feedback-status{font-weight:600;margin-bottom:10px}.verdict{border-radius:8px;padding:6px 12px;font-size:12px;font-weight:600}.verdict-correct{color:#176244;background:#e9f7ef;border-color:#cae7d7}.verdict-incorrect{color:#a22836;background:#fff0f2;border-color:#f1cbd1}.verdict-needs_review,.verdict-needs_resubmission{color:#855311;background:#fff5df;border-color:#ead7b6}.grading-error{border-left:3px solid #c94758;padding:1px 14px 12px;background:#fff8f9;margin:16px 0;border-radius:4px}.grading-error p{margin:8px 0}.reference-answer{background:#f5f8ff;border:1px solid #dce6fa;border-radius:12px;padding:4px 18px 14px;margin-top:20px}.reference-answer p{margin:10px 0}.graded-question details{margin-top:16px;font-size:13px}.graded-question summary{cursor:pointer;min-height:44px;display:list-item;padding:10px 0;color:var(--blue)}.submitted-working{max-width:100%;max-height:400px;display:block;margin:12px 0;border-radius:8px;border:1px solid var(--border)}.transcription{white-space:pre-wrap;background:var(--surface);padding:12px;border-radius:8px}.question-footer a:last-child{max-width:100%;text-align:center}.grade-counts span{white-space:nowrap}@media(max-width:760px){.grading-summary{flex-wrap:wrap}.graded-question{padding:20px}.graded-split{grid-template-columns:1fr;gap:22px}.feedback{border:0;border-top:1px solid var(--border);padding:20px 0 0}.graded-question h2 .preview-note{display:block;margin:4px 0 0}.grade-counts{width:100%;justify-content:space-between}.result-nav button{font-size:12px}.question-footer{flex-wrap:wrap}}@media(prefers-reduced-motion:reduce){.spinner{animation:none}}

.ink-reference,.ink-image-tools{display:flex;gap:8px;align-items:center;flex-wrap:wrap;margin:12px 0}.ink-reference span{font-size:13px;color:var(--muted,#596779)}.ink-gallery{display:flex;gap:12px;overflow:auto;padding:12px;background:#f4f7fc;border-radius:12px}.ink-gallery button{display:grid;gap:8px;min-width:120px;max-width:180px}.ink-gallery img{height:90px;max-width:155px;object-fit:contain}.ink-image-tools label{display:flex;gap:8px;align-items:center}.ink-image-tools select{padding:10px;border:1px solid #d8e0eb;border-radius:8px}.ink-gallery[hidden],.ink-image-tools[hidden]{display:none}#ink-dialog{max-height:95dvh;overflow:auto}.ink-tools button,.ink-reference button,.ink-image-tools button{min-height:44px}.ink-reference button[aria-pressed=true]{background:#eaf0ff;color:#145af5}

.correction-note{padding:16px;background:#eef4ff;border-radius:12px;color:#244a85}.review-request{float:right;margin:0 0 12px 12px;min-height:44px}.reviewed-label{display:inline-block;background:#eef4ff;border-radius:6px;padding:4px 8px;color:#365989;margin:4px 8px 12px 0}.mastered-label{color:#176348}.topic-section{margin-top:32px;padding:24px;background:white;border:1px solid #dce3ec;border-radius:18px}.topic-section table{width:100%;text-align:left;border-collapse:collapse}.topic-section th,.topic-section td{padding:14px;border-bottom:1px solid #e7ebf1}.feedback p{white-space:pre-wrap}#review-dialog{width:min(560px,90vw);border:1px solid #d8e0eb;border-radius:18px;padding:24px}#review-dialog textarea{display:block;width:100%;margin-top:12px}#review-dialog::backdrop{background:#17263b66}

#ink-dialog .canvas-wrap{display:grid;place-items:center}#ink-dialog #ink-canvas{width:auto;max-width:100%;height:min(48dvh,500px)}

/* Full-screen writing workspace. Only the question pane may scroll. */
html.ink-open,html.ink-open body{overflow:hidden;overscroll-behavior:none}
#ink-dialog{position:fixed;inset:0;margin:0;border:0;border-radius:0;padding:0;width:100%;max-width:none;height:100dvh;max-height:none;overflow:hidden;overscroll-behavior:none;touch-action:none;background:#f5f7fa;box-sizing:border-box}
#ink-dialog[open]{display:flex;flex-direction:column}
#ink-dialog .ink-head{flex:none;gap:16px;min-height:72px;padding:12px max(20px,env(safe-area-inset-right)) 12px max(20px,env(safe-area-inset-left));border-bottom:1px solid var(--border);background:white}
#ink-dialog .ink-head h2{margin:0;font-size:18px}
#ink-dialog button{min-height:44px;touch-action:manipulation}
#ink-dialog .ink-workspace{display:grid;grid-template-columns:minmax(240px,35%) minmax(0,1fr);flex:1;min-height:0;padding-bottom:env(safe-area-inset-bottom)}
#ink-dialog .ink-question{overflow:auto;min-width:0;padding:24px;touch-action:pan-y pinch-zoom;overscroll-behavior:contain;background:white;border-right:1px solid var(--border);-webkit-overflow-scrolling:touch}
#ink-dialog .ink-question h3{margin:0 0 20px;font-size:18px}
#ink-dialog .ink-question img{max-width:100%;height:auto;display:block;margin:16px auto}
#ink-dialog .ink-question .katex-display{overflow-x:auto;overflow-y:hidden;touch-action:pan-x}
#ink-dialog .ink-options>div{display:flex;gap:12px;margin:16px 0;padding-top:12px;border-top:1px solid var(--border)}
#ink-dialog .ink-options>div>div{min-width:0}
#ink-dialog .ink-writing{display:flex;flex-direction:column;min-height:0;min-width:0;padding:12px 16px 8px;gap:8px;touch-action:none}
#ink-dialog .ink-tools,#ink-dialog .ink-reference,#ink-dialog .ink-image-tools{margin:0;flex:none;gap:8px}
#ink-dialog .ink-tools label{margin-left:auto;font-size:13px}
#ink-dialog .ink-reference span{display:none}
#ink-dialog .canvas-wrap{flex:1;min-height:0;min-width:0;display:grid;place-items:center;touch-action:none;overscroll-behavior:none;background:#e9edf3;border-radius:12px}
#ink-dialog #ink-canvas{width:auto;height:auto;max-width:none;max-height:none;flex:none;touch-action:none;-webkit-touch-callout:none}
#ink-dialog #ink-error{flex:none;min-height:20px;line-height:20px;font-size:13px;margin:0}
#ink-dialog .ink-gallery{max-height:140px;flex:none;touch-action:pan-x;overscroll-behavior:contain}
#ink-dialog .ink-image-tools{max-height:112px;overflow:auto;touch-action:pan-y;overscroll-behavior:contain}
@media(max-width:700px){#ink-dialog .ink-workspace{grid-template-columns:1fr;grid-template-rows:30% minmax(0,1fr)}#ink-dialog .ink-question{padding:12px;border-right:0;border-bottom:1px solid var(--border)}#ink-dialog .ink-head{padding:8px;gap:8px}#ink-dialog .ink-head h2{font-size:14px}#ink-dialog .ink-writing{padding:8px}#ink-dialog .ink-tools label{margin-left:0}}

.shared-material{border-bottom:1px solid #dce3ed;padding-bottom:20px;margin-bottom:24px}.shared-material h3{font-size:19px}.shared-material p{white-space:pre-wrap}.response-part{border:1px solid #dce3ed;border-radius:12px;padding:12px;margin:16px 0}.response-part legend{font-weight:600;padding:0 6px}

@media(min-width:800px){.reading-workspace{height:calc(100dvh - 245px);min-height:380px;align-items:stretch}.reading-workspace>.question-card,.reading-workspace>.response-card{overflow:auto;overscroll-behavior:contain;min-height:0;touch-action:pan-y pinch-zoom}}

.response-part:disabled{background:#f2f5f8;opacity:1}.response-part:disabled textarea{color:#44546a;background:#eef2f6}.part-grade{padding:14px 0;border-bottom:1px solid #dce4ee}.part-grade h3{display:flex;gap:12px;align-items:center}.exception-note{padding:14px;background:#fff5df;border-radius:12px;color:#714611}

/* Student answer tools: touch-first, shared attachments and recoverable uploads. */
.answer-tools{display:flex;flex-wrap:wrap;gap:8px;margin:10px 0 6px}.answer-tools button{min-height:44px;padding:8px 12px;font-size:14px;color:var(--blue)}.answer-preview{padding:12px;background:#f5f8ff;border:1px solid #dbe5f7;border-radius:10px;overflow-x:auto;font-size:18px}.answer-preview[hidden]{display:none}.working-note{margin-top:24px}#upload-progress{display:flex;gap:12px;align-items:center;justify-content:space-between;background:white;border:1px solid #c2d3fa;padding:12px;border-radius:10px;margin-top:12px;font-size:14px}#upload-progress[hidden]{display:none}#upload-progress button{min-height:44px;flex-shrink:0}.difficulty-control{border:0;border-top:1px solid var(--border);padding:20px 0 0;margin:24px 0 0}.difficulty-control legend{font-size:15px;font-weight:600}.difficulty-control legend span{font-size:12px;font-weight:400;color:var(--muted);margin-left:10px}.difficulty-control>div{display:flex;gap:8px;flex-wrap:wrap}.difficulty-control button{min-height:44px;font-size:14px}.difficulty-control button[aria-pressed=true]{border-color:var(--blue);background:var(--tint);color:var(--blue)}.formula-dialog{width:min(640px,94vw);padding:24px}.formula-dialog h2{font-size:22px}.formula-dialog p{margin:12px 0;color:var(--muted)}.formula-dialog label{display:grid;gap:8px;margin:16px 0}.formula-dialog input,.formula-dialog select{font:inherit;width:100%;min-height:48px;padding:10px;border:1px solid #c7d1e0;border-radius:10px}.formula-fields{display:grid;grid-template-columns:1fr 1fr;gap:16px}.formula-fields label[hidden]{display:none}.formula-symbols{display:flex;flex-wrap:wrap;gap:8px}.formula-symbols button{min-width:44px;min-height:44px;font-size:20px}#formula-preview{min-height:100px;display:grid;place-items:center;overflow:auto;background:#f5f8ff;border-radius:12px;padding:20px;margin-top:16px}.pending-dialog{width:min(560px,94vw)}.pending-dialog p{margin:16px 0}.pending-list{display:flex;gap:10px;flex-wrap:wrap}.working-image img{max-height:140px;width:auto}.question-navigation{flex-wrap:wrap}.question-footer{gap:12px;flex-wrap:wrap}.question-footer button{min-height:44px}@media(max-width:600px){.formula-fields{grid-template-columns:1fr}.answer-tools button{flex-grow:1}#upload-progress{flex-wrap:wrap}.formula-dialog{padding:16px}}@media(prefers-reduced-motion:reduce){*{scroll-behavior:auto!important}}

.assignment-footer{position:sticky;bottom:0;padding:12px 16px max(12px,env(safe-area-inset-bottom));background:#fff;border:1px solid var(--border);border-radius:14px;z-index:3;box-shadow:0 -6px 20px #17263b08}.response-card>.difficulty-control{margin:8px 0 20px;padding:0;border:0}.image-answer-menu{width:min(440px,94vw)}.image-answer-menu p{margin:12px 0 20px}.image-answer-actions{display:grid;gap:10px;margin-bottom:16px}.image-answer-actions button{min-height:48px}.image-answer-menu>button{min-height:44px}