:root{--blue:#0076b8;--ink:#243345;--muted:#6f7c8e;--line:#dfe5eb;--green:#16764b;--green-bg:#e8f5ed;--yellow:#8a6500;--yellow-bg:#fff5bc;--red:#b02e34;--red-bg:#fff0f0;--lemon:#f2ef70}*{box-sizing:border-box}body{margin:0;font:15px/1.65 'Malgun Gothic','Apple SD Gothic Neo',sans-serif;color:var(--ink);background:#fff}button,input,textarea,select{font:inherit}button,a{touch-action:manipulation}a{color:var(--blue);text-decoration:none}a:hover{text-decoration:underline}button{cursor:pointer;border:1px solid #cdd5dd;border-radius:4px;padding:9px 16px;background:#fff;color:var(--ink)}button:hover{background:#f2f6f9}button:disabled{opacity:.5;cursor:not-allowed}button:focus-visible,a:focus-visible,input:focus-visible,textarea:focus-visible,select:focus-visible{outline:3px solid #62ade0;outline-offset:3px}.primary{background:var(--blue);border-color:var(--blue);color:white}.primary:hover{background:#00639d}.top{max-width:1320px;margin:auto;padding:25px 28px;border-bottom:1px solid var(--line);display:flex;align-items:center;gap:20px;flex-wrap:wrap}.brand{font-size:24px;font-weight:700;letter-spacing:-1px;white-space:nowrap}.brand span{font-weight:300}.brand i{font-style:normal;color:#72b8db;margin-left:8px}.course{color:var(--muted);font-size:13px}.top nav{margin-left:auto;display:flex;gap:22px;font-size:14px}main{max-width:1264px;margin:40px auto 80px;padding:0 28px;min-height:65vh}h1{font-weight:400;font-size:32px;line-height:1.4;margin:8px 0 28px}h2{font-size:23px;font-weight:500;margin:0 0 18px}h3{font-size:17px;font-weight:600;margin:0 0 14px}.eyebrow{font-size:12px;color:var(--blue);letter-spacing:1.5px;font-weight:700}.muted{color:var(--muted)}.lookup{max-width:520px;margin:75px auto}.lookup>p{margin-bottom:30px}.panel{border:1px solid var(--line);border-radius:6px;padding:28px;background:white}label{display:block;margin-bottom:18px;font-size:14px}input,textarea,select{display:block;width:100%;border:1px solid #cbd4df;border-radius:4px;padding:11px 12px;background:white;color:var(--ink);margin-top:6px}textarea{resize:vertical;min-height:110px}.lookup .primary{width:100%;margin-top:8px}.error-text{color:var(--red);min-height:24px}.row{display:flex;align-items:center;gap:12px;flex-wrap:wrap}.between{justify-content:space-between}.score-card{display:flex;align-items:center;justify-content:space-between;gap:20px;margin:25px 0;padding:32px;border-left:4px solid var(--blue);background:#f7fafd}.score-card h1{margin:0 0 4px;font-size:24px}.score{font-size:64px;line-height:1.2;font-variant-numeric:tabular-nums;color:var(--blue);font-weight:600;white-space:nowrap}.score small{font-size:22px;color:var(--muted);font-weight:400}.chart-panel{margin-top:30px}.chart-scroll{overflow:auto}.histogram{display:block;width:100%;min-width:640px;max-height:340px}.legend{display:flex;gap:20px;align-items:center;flex-wrap:wrap;font-size:13px;color:var(--muted)}.swatch{display:inline-block;width:14px;height:14px;background:#b8bec6;border:1px solid #9fa7b0;margin-right:6px;vertical-align:middle}.swatch.own{background:var(--lemon);border-color:#c2b73c}.feedback-action{margin:28px 0;display:flex;justify-content:center}.feedback-action button{min-width:200px}.review-layout{display:grid;grid-template-columns:minmax(0,1fr) 242px;gap:28px;align-items:start}.question-panel{min-width:0}.question-heading{border-bottom:1px solid var(--line);padding:22px 0;margin-bottom:24px}.question-heading h2{margin:8px 0 16px}.badge{display:inline-block;border-radius:4px;padding:3px 10px;font-size:13px;font-weight:600}.correct{background:var(--green-bg);color:var(--green);border-color:#a8d7bd}.partial{background:var(--yellow-bg);color:var(--yellow);border-color:#dbc96d}.incorrect{background:var(--red-bg);color:var(--red);border-color:#edb5b8}.ungraded{background:#f0f3f6;color:var(--muted)}.prose{white-space:pre-wrap;overflow-wrap:anywhere}.question-image{max-width:100%;max-height:520px;object-fit:contain}.navigator{position:sticky;top:20px}.number-grid{display:grid;grid-template-columns:repeat(5,1fr);gap:7px;margin:16px 0}.number-grid button{padding:6px 0;font-size:15px;min-height:49px;font-variant-numeric:tabular-nums}.number-grid small{display:block;font-size:11px;line-height:1.1}.number-grid [aria-current=step]{outline:2px solid var(--blue);outline-offset:2px}.number-grid +.legend{display:block;line-height:2}.option{padding:13px 16px;margin:8px 0;border:1px solid var(--line);border-left:4px solid transparent;display:flex;gap:14px;align-items:flex-start}.option.correct{border-left-color:var(--green)}.option.incorrect{border-left-color:var(--red)}.option code{white-space:pre-wrap}.option em{margin-left:auto;white-space:nowrap;font:12px/2 sans-serif}.explanation{border-top:1px solid var(--line);margin-top:26px;padding-top:22px}.code-grid{display:grid;grid-template-columns:minmax(0,1fr) minmax(0,1fr);gap:16px;margin:24px 0}.code-column{min-width:0}.code-column h3{font-weight:500}.code-lines{border:1px solid var(--line);background:#fafbfd;overflow:auto;max-height:620px}.code-line{display:flex;min-height:30px;min-width:max-content;font:13px/1.8 Consolas,'Courier New',monospace;padding:3px 8px 3px 0}.code-line .line-no{display:inline-block;text-align:right;min-width:35px;width:35px;color:#8591a1;user-select:none;padding-right:9px}.code-line code{white-space:pre;padding:0 12px 0 5px;color:inherit}.line-dot{flex:0 0 22px;width:22px;height:23px;border:0;background:transparent!important;padding:0;font-size:16px;color:inherit}.line-dot:disabled{opacity:1}.code-line.correct{background:#e8f5ed}.code-line.incorrect{background:#ffe8e8}.code-line.partial{background:#fff5c5}.line-reason{padding:18px 22px;margin:18px 0;border:1px solid var(--line);border-left-width:4px;min-height:75px}.line-reason:empty{display:none}.grade-tools{border:1px solid #cfdae6;border-radius:5px;padding:22px;margin:24px 0;background:#fbfcfe}.grade-tools .quick{display:flex;gap:10px;flex-wrap:wrap;margin-bottom:18px}.grade-tools input[type=number]{max-width:180px}.save-bar{display:flex;gap:10px;flex-wrap:wrap;margin-top:24px}.grade-tools label{margin-top:16px}.table-wrap{overflow:auto}table{border-collapse:collapse;width:100%;font-size:14px}th,td{padding:13px 12px;border-bottom:1px solid var(--line);text-align:left;white-space:nowrap}th{background:#f6f8fa;font-weight:500;color:#556575}td button{font-size:13px;padding:5px 10px}tr:hover td{background:#fbfcfd}.dashboard-stat{display:flex;gap:34px;margin:30px 0}.dashboard-stat strong{font-size:30px;display:block;font-weight:500;color:var(--blue)}.dashboard-stat span{color:var(--muted);font-size:13px}.student-picker{max-width:360px;margin-bottom:24px}.admin-actions{display:flex;gap:10px;flex-wrap:wrap;margin-bottom:22px}.warning-note{color:#815e16;background:#fff9e5;padding:12px 16px;border-left:3px solid #e4c362;font-size:14px}dialog{border:1px solid var(--line);border-radius:8px;padding:28px;max-width:560px;width:calc(100% - 32px);color:var(--ink)}dialog::backdrop{background:#20304466}dialog pre{white-space:pre-wrap;background:#f5f7fa;padding:12px;overflow-wrap:anywhere}#notice{position:fixed;bottom:24px;left:50%;transform:translateX(-50%);background:#233143;color:white;padding:12px 20px;border-radius:4px;z-index:50;display:none;max-width:90vw}footer{max-width:1264px;margin:auto;border-top:1px solid var(--line);padding:25px 28px;color:#7e8a99;font-size:13px}footer span{float:right}.empty{padding:40px;text-align:center;color:var(--muted)}.question-switch{margin-top:24px;display:flex;justify-content:space-between}.only-print{display:none}@media(max-width:800px){.top{padding:16px;gap:8px}.top nav{width:100%;margin:8px 0 0;gap:20px}.course{margin-left:auto}main{padding:0 16px;margin-top:25px}.review-layout{grid-template-columns:1fr}.navigator{position:static;grid-row:1;padding:16px}.number-grid{grid-template-columns:repeat(10,1fr);gap:5px}.number-grid button{font-size:13px}.navigator .legend{display:flex}.code-grid{grid-template-columns:1fr}.panel{padding:20px}.score-card{padding:22px;flex-wrap:wrap}.score{font-size:52px}.lookup{margin:40px auto}.dashboard-stat{gap:22px}.brand{font-size:21px}}@media print{.top nav,.admin-actions,.grade-tools,.save-bar,.feedback-action,#notice,button{display:none!important}main{padding:0;margin:0}.navigator{position:static}.review-layout{display:block}.score-card{break-inside:avoid}.code-lines{max-height:none}.only-print{display:block}}

/* Range feedback and student preview. Only the question navigator is sticky. */
.top .course{margin-left:auto}
.lookup{max-width:440px}
.lookup h1,.lookup>p{text-align:center}
.lookup h1{margin-bottom:12px}
[hidden]{display:none!important}
.sr-only{position:absolute;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;clip-path:inset(50%);white-space:nowrap;border:0}
.preview-bar{display:flex;align-items:center;justify-content:space-between;gap:16px;padding:14px 18px;margin-bottom:26px;background:#f0f7fc;border:1px solid #c9dfee;border-radius:5px;color:#256087}
.preview-bar span{font-weight:600}
.preview-bar button{background:#fff;font-size:14px}
.review-total{margin:0 0 18px;font-size:14px}
.navigator{padding:22px;z-index:5}
.navigator h3{font-size:20px;font-weight:400;margin-bottom:17px}
.number-grid{margin:0;gap:7px}
.number-grid button{min-height:40px;border-radius:0;line-height:1.3}
.number-grid button.correct:hover{background:#d4eddf}
.number-grid button.partial:hover{background:#ffec90}
.number-grid button.incorrect:hover{background:#ffd5d7}
.number-grid [aria-current=step]{outline-width:2px;outline-offset:1px}
.code-lines{overscroll-behavior:contain;scroll-padding:12px}
.code-line{border-left:3px solid transparent}
.code-line.correct{border-left-color:#3c9a6b}
.code-line.partial{border-left-color:#c9a526}
.code-line.incorrect{border-left-color:#d45b60}
.code-line[role=button]{cursor:pointer}
.code-line[role=button]:focus-visible{outline:2px solid var(--blue);outline-offset:-2px}
.code-line .line-no{flex:0 0 40px;min-width:40px;width:40px;font:inherit;text-align:right;padding:0 10px 0 2px;border:0;border-radius:0;background:transparent;color:#71839a;line-height:24px;user-select:none}
.code-line button.line-no{cursor:ns-resize;touch-action:none}
.code-line button.line-no:hover{background:#c7e4f6;color:#16497a}
.code-line.range-selected{background:#1b579b!important;color:white;border-left-color:#173f75}
.code-line.range-selected .line-no{color:white}
.range-selectable ::selection{background:#154f96;color:white}
.range-help{font-size:13px;margin:12px 0 10px}
#manual-range{font-size:13px;padding:6px 10px}
.range-editor{margin-top:16px;padding:18px;background:#f7faff;border:1px solid #b9cfe2;border-top:3px solid #2775b0;border-radius:4px}
.range-fields{display:flex;align-items:center;gap:12px;max-width:240px}
.range-fields label{flex:1;min-width:0;margin:0 0 15px}
.range-fields input{padding:6px 10px}
.range-colors{display:flex;gap:8px;flex-wrap:wrap;margin:0 0 16px}
.range-colors button{padding:7px 12px;font-size:13px}
.range-colors [aria-pressed=true]{outline:2px solid currentColor;outline-offset:2px}
.range-editor textarea{min-height:100px;font-size:14px;line-height:1.7}
.range-editor label{margin-bottom:10px}
.range-editor .error-text:empty{display:none}
.range-editor .row button{font-size:13px;padding:8px 12px}
.range-notes{margin:25px 0}
.range-note{border:1px solid var(--line);border-left:4px solid;margin:12px 0;padding:14px 18px;border-radius:4px}
.range-note.correct{border-left-color:#3c9a6b}
.range-note.partial{border-left-color:#c9a526}
.range-note.incorrect{border-left-color:#d45b60}
.range-note p{margin:7px 0 0;font-size:14px}
.range-note button{font-size:12px;padding:3px 9px;background:#ffffffa6}
.range-note .note-location{font-weight:600;font-size:14px;color:inherit;border:0;background:transparent;padding:0;text-decoration:underline;text-underline-offset:4px}
.code-hover-hint{position:fixed;z-index:80;max-width:min(360px,calc(100vw - 24px));padding:14px 17px;border:1px solid;border-radius:6px;box-shadow:0 5px 22px #20304426;pointer-events:none;font-size:13px;line-height:1.7;overflow-wrap:anywhere}
.code-hover-hint p{margin:5px 0 0;white-space:pre-wrap}
.inline-code-note{position:sticky;left:0;width:100%;min-width:0;padding:16px;border:1px solid;border-left:0;border-right:0;font:14px/1.75 'Malgun Gothic',sans-serif;overflow-wrap:anywhere}
.inline-code-note p{margin:8px 0 13px}
.inline-code-note button{font-size:13px;padding:6px 12px;background:#fff}
@media(max-width:800px){
 .navigator{position:sticky;top:0;grid-row:1;padding:10px 12px;border-radius:0;box-shadow:0 3px 8px #2433450b;background:#fffffff5;backdrop-filter:blur(8px)}
 .navigator h3{font-size:14px;margin:0 0 7px}
 .number-grid{grid-template-columns:repeat(10,minmax(0,1fr));gap:5px}
 .number-grid button{min-height:34px;font-size:13px}
 .review-layout{gap:12px}
 .code-grid{gap:24px}
 .code-line{font-size:12px}
 .code-lines{max-height:460px}
 .range-editor{padding:15px}
 .preview-bar{padding:12px;gap:12px;align-items:flex-start}
 .preview-bar span{font-size:14px}
 .preview-bar button{font-size:12px;padding:7px 10px}
 .code-hover-hint{display:none}
}
@media print{.preview-bar,.navigator,.range-editor,.range-help,#manual-range,.code-hover-hint{display:none!important}.range-note{break-inside:avoid}.inline-code-note{position:static}}
.feedback-image-editor{margin-top:24px;border-top:1px solid var(--line);padding-top:18px}
.feedback-image-editor h4{margin:0 0 12px;font-size:16px;font-weight:500}
.image-dropzone{border:1px dashed #acbccd;background:#fff;padding:20px;text-align:center;border-radius:5px}
.image-dropzone.drag-over,.image-dropzone:focus{background:#edf7ff;border-color:var(--blue)}
.image-dropzone p{margin:10px 0 5px;font-size:13px}.image-dropzone small{color:var(--muted)}
#image-upload-status:empty{display:none}
.feedback-gallery{display:grid;grid-template-columns:repeat(auto-fit,minmax(min(100%,280px),1fr));gap:18px;margin-top:18px}
.feedback-gallery:empty{display:none}
.feedback-figure{margin:0;padding:12px;border:1px solid var(--line);background:white;border-radius:5px;min-width:0}
.feedback-image-open{display:block;width:100%;padding:0;border:0;background:#f8fafc;cursor:zoom-in;line-height:0}
.feedback-image-open img{width:100%;max-height:420px;object-fit:contain}
.feedback-figure figcaption{margin-top:10px;font-size:14px}.feedback-figure label{font-size:13px}
.feedback-figure .image-remove{font-size:13px;padding:5px 10px;color:var(--red);margin-top:8px}
#feedback-image-dialog{max-width:1100px;width:calc(100vw - 32px);max-height:94vh;overflow:auto;padding:20px}
#feedback-image-dialog h2{font-size:20px;margin:0}.feedback-image-large{display:block;max-width:100%;height:auto;margin:20px auto 0}
@media(max-width:800px){.feedback-gallery{grid-template-columns:1fr}.image-dropzone{padding:16px}.feedback-image-open img{max-height:360px}}
@media print{.feedback-gallery{display:block}.feedback-figure{break-inside:avoid}.feedback-image-open{display:block!important}}