@import "https://cdn.jsdelivr.net/npm/katex@0.16.11/dist/katex.min.css";
@import "https://cdn.jsdelivr.net/gh/orioncactus/pretendard@v1.3.9/dist/web/variable/pretendardvariable-dynamic-subset.min.css";
:root{--bg:#fff;--bg-subtle:#f8f9fa;--border:#e5e7eb;--border-strong:#d1d5db;--text-primary:#111827;--text-secondary:#6b7280;--text-muted:#9ca3af;--accent:#4f46e5;--accent-hover:#4338ca;--accent-light:#eef2ff;--success:#059669;--success-light:#ecfdf5;--warning:#d97706;--warning-light:#fffbeb;--danger:#dc2626;--danger-light:#fef2f2;--radius:6px;--shadow-sm:0 1px 2px #0000000a;--shadow:0 1px 3px #0000000f, 0 1px 2px #0000000a;--transition:.15s cubic-bezier(.4, 0, .2, 1)}*{box-sizing:border-box;margin:0;padding:0}html{height:100%}html,body{max-width:100vw;overflow-x:hidden}body{min-height:100%;color:var(--text-primary);background:var(--bg);-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale;flex-direction:column;font-family:Pretendard Variable,Pretendard,-apple-system,BlinkMacSystemFont,system-ui,sans-serif;font-size:15px;line-height:1.6;display:flex}a{color:inherit;text-decoration:none}.site-header{border-bottom:1px solid var(--border);background:var(--bg);z-index:100;justify-content:space-between;align-items:center;height:56px;padding:0 40px;display:flex;position:sticky;top:0}.site-logo{letter-spacing:-.5px;color:var(--text-primary);font-size:17px;font-weight:700}.site-logo span{color:var(--accent)}.main-container{flex:1;width:100%;max-width:1120px;margin:0 auto;padding:40px 24px}.section-title{letter-spacing:-.3px;margin-bottom:8px;font-size:22px;font-weight:700}.section-desc{color:var(--text-secondary);margin-bottom:28px;font-size:14px}.steps-bar{border-bottom:2px solid var(--border);align-items:center;gap:0;margin-bottom:40px;display:flex}.step-item{color:var(--text-muted);cursor:pointer;transition:color var(--transition);-webkit-user-select:none;user-select:none;white-space:nowrap;padding:12px 28px;font-size:14px;font-weight:500;position:relative}.step-item:after{content:"";height:2px;transition:background var(--transition);background:0 0;position:absolute;bottom:-2px;left:0;right:0}.step-item:hover{color:var(--text-secondary)}.step-item.active{color:var(--accent);font-weight:600}.step-item.active:after{background:var(--accent)}.step-item.completed{color:var(--success)}.step-item.completed:after{background:var(--success)}.step-number{border:1.5px solid;border-radius:50%;justify-content:center;align-items:center;width:22px;height:22px;margin-right:8px;font-size:12px;font-weight:600;display:inline-flex}.step-item.active .step-number{background:var(--accent);color:#fff;border-color:var(--accent)}.step-item.completed .step-number{background:var(--success);color:#fff;border-color:var(--success)}.upload-zone{border:1px solid var(--border);border-radius:var(--radius);text-align:center;transition:all var(--transition);cursor:pointer;background:var(--bg);padding:64px 40px}.upload-zone:hover,.upload-zone.drag-over{border-color:var(--accent);background:var(--accent-light);border-style:solid}.upload-zone-icon{color:var(--text-muted);transition:color var(--transition);margin-bottom:16px;font-size:40px}.upload-zone:hover .upload-zone-icon{color:var(--accent)}.upload-zone-text{color:var(--text-secondary);margin-bottom:6px;font-size:15px;font-weight:500}.upload-zone-sub{color:var(--text-muted);font-size:13px}.btn{border-radius:var(--radius);cursor:pointer;transition:all var(--transition);white-space:nowrap;border:none;align-items:center;gap:6px;padding:8px 18px;font-family:inherit;font-size:14px;font-weight:500;display:inline-flex}.btn:disabled{opacity:.5;cursor:not-allowed}.btn-primary{background:var(--accent);color:#fff}.btn-primary:hover:not(:disabled){background:var(--accent-hover)}.btn-secondary{background:var(--bg);color:var(--text-primary);border:1px solid var(--border-strong)}.btn-secondary:hover:not(:disabled){background:var(--bg-subtle);border-color:var(--text-muted)}.btn-ghost{color:var(--text-secondary);background:0 0}.btn-ghost:hover:not(:disabled){background:var(--bg-subtle);color:var(--text-primary)}.btn-danger{background:var(--danger);color:#fff}.btn-danger:hover:not(:disabled){background:#b91c1c}.btn-sm{padding:5px 12px;font-size:13px}.btn-lg{padding:11px 24px;font-size:15px}.problem-list{flex-direction:column;gap:0;display:flex}.problem-row{border-bottom:1px solid var(--border);grid-template-columns:48px 1fr auto;align-items:start;gap:16px;padding:20px 0;display:grid}.problem-row:first-child{border-top:1px solid var(--border)}.problem-num{color:var(--text-primary);padding-top:2px;font-size:18px;font-weight:700}.problem-content{flex:1;min-width:0}.problem-question{color:var(--text-primary);margin-bottom:8px;font-size:15px;line-height:1.7}.problem-equation{background:var(--bg-subtle);border-left:3px solid var(--accent);border-radius:0 var(--radius) var(--radius) 0;margin:8px 0;padding:10px 16px;overflow-x:auto}.problem-answer{color:var(--text-secondary);margin-top:8px;font-size:13px}.problem-answer strong{color:var(--accent);font-weight:600}.problem-actions{flex-shrink:0;gap:4px;display:flex}.problem-preview{border:1px solid var(--border);border-radius:var(--radius);margin-top:14px;overflow:hidden}.problem-preview-label{background:var(--bg-subtle);border-bottom:1px solid var(--border);color:var(--text-muted);text-transform:uppercase;letter-spacing:.5px;padding:6px 14px;font-size:11px;font-weight:600}.problem-preview-body{padding:16px 20px;font-size:15px;line-height:1.85}.preview-question-text{margin-bottom:4px;display:block}.preview-options{flex-direction:column;gap:3px;margin-top:10px;display:flex}.preview-option-item{padding:2px 0;font-size:14px;line-height:1.7;display:block}.json-editor-panel{border:1px solid var(--border);border-radius:var(--radius);grid-template-columns:1fr 1fr;gap:0;min-height:400px;display:grid;overflow:hidden}.json-editor-left{border-right:1px solid var(--border)}.json-editor-header{background:var(--bg-subtle);border-bottom:1px solid var(--border);color:var(--text-secondary);justify-content:space-between;align-items:center;padding:10px 16px;font-size:13px;font-weight:600;display:flex}.json-textarea{resize:vertical;width:100%;min-height:360px;color:var(--text-primary);background:var(--bg);border:none;outline:none;padding:16px;font-family:SF Mono,Consolas,Monaco,monospace;font-size:13px;line-height:1.6}.json-textarea:focus{background:#fafbff}.json-preview{max-height:500px;padding:20px;overflow-y:auto}.toolbar{flex-wrap:wrap;justify-content:space-between;align-items:center;gap:12px;margin-bottom:20px;display:flex}.toolbar-group{align-items:center;gap:8px;display:flex}.exam-sheet{border:1px solid var(--border);color:#1a1a1a;background:#fff;max-width:800px;margin:0 auto;padding:40px 36px;font-size:14px;line-height:1.7}.exam-header{text-align:center;border-bottom:3px double #333;margin-bottom:0;padding-bottom:16px}.exam-school{color:#555;letter-spacing:2px;margin-bottom:4px;font-size:13px}.exam-title{letter-spacing:-.3px;margin:0 0 2px;font-size:22px;font-weight:800}.exam-subtitle{color:#555;font-size:14px;font-weight:500}.exam-meta{color:#555;border-bottom:1px solid #ccc;justify-content:space-between;padding:8px 0;font-size:12px;display:flex}.exam-meta-left,.exam-meta-right{gap:16px;display:flex}.exam-info-row{border-bottom:2px solid #333;gap:12px;margin-bottom:20px;padding:10px 0 16px;display:flex}.exam-info-field{flex:1;align-items:center;gap:6px;display:flex}.exam-info-label{white-space:nowrap;font-size:13px;font-weight:700}.exam-info-blank{border-bottom:1px solid #999;flex:1;min-width:40px;height:20px}.exam-problems-grid{column-count:2;column-rule:1px solid #e0e0e0;column-gap:28px}.exam-problem{break-inside:avoid;page-break-inside:avoid;-webkit-column-break-inside:avoid;border-bottom:.5px solid #e8e8e8;width:100%;margin-bottom:4px;padding-bottom:16px;display:inline-block}.exam-problem:last-child{border-bottom:none}.exam-problem-header{align-items:baseline;gap:6px;margin-bottom:4px;display:flex}.exam-problem-num{flex-shrink:0;font-size:15px;font-weight:800}.exam-problem-points{color:#888;font-size:11px;font-weight:500}.exam-problem-body{padding-left:20px;font-size:13px;line-height:1.75}.exam-answer-box{border-left:2px solid var(--accent);background:#f5f5f5;border-radius:0 4px 4px 0;margin-top:10px;padding:8px 12px;font-size:12px}.exam-answer-label{color:var(--accent);margin-bottom:4px;font-weight:700}.form-group{flex-direction:column;gap:4px;display:flex}.form-label{color:var(--text-secondary);font-size:13px;font-weight:600}.form-input{border:1px solid var(--border);border-radius:var(--radius);color:var(--text-primary);background:var(--bg);transition:border-color var(--transition);outline:none;padding:8px 12px;font-family:inherit;font-size:14px}.form-input:focus{border-color:var(--accent)}.form-row{grid-template-columns:repeat(auto-fill,minmax(200px,1fr));gap:16px;margin-bottom:24px;display:grid}.loading-overlay{color:var(--text-secondary);flex-direction:column;justify-content:center;align-items:center;gap:16px;padding:60px 40px;display:flex}.spinner{border:3px solid var(--border);border-top-color:var(--accent);border-radius:50%;width:32px;height:32px;animation:.8s linear infinite spin}@keyframes spin{to{transform:rotate(360deg)}}.loading-text{font-size:14px;font-weight:500}.badge{border-radius:100px;align-items:center;gap:4px;padding:3px 10px;font-size:12px;font-weight:500;display:inline-flex}.badge-success{background:var(--success-light);color:var(--success)}.badge-info{color:#2563eb;background:#eff6ff}.badge-accent{background:var(--accent-light);color:var(--accent)}.badge-warning{background:var(--warning-light);color:var(--warning)}.badge-danger{background:var(--danger-light);color:var(--danger)}.empty-state{text-align:center;color:var(--text-muted);padding:60px 40px}.empty-state-icon{margin-bottom:12px;font-size:48px}.empty-state-text{font-size:15px;font-weight:500}.form-select{border:1px solid var(--border);border-radius:var(--radius);color:var(--text-primary);background:var(--bg) url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' viewBox='0 0 24 24' fill='none' stroke='%236b7280' stroke-width='2'%3E%3Cpath d='M6 9l6 6 6-6'/%3E%3C/svg%3E") no-repeat right 10px center;appearance:none;cursor:pointer;transition:border-color var(--transition);outline:none;padding:8px 32px 8px 12px;font-family:inherit;font-size:14px}.form-select:focus{border-color:var(--accent)}@page{size:A4;margin:12mm 10mm}@media print{.site-header,.steps-bar,.toolbar,.no-print{display:none!important}body{-webkit-print-color-adjust:exact;print-color-adjust:exact;margin:0;font-size:10pt}.main-container{max-width:100%;margin:0;padding:0}.exam-sheet{box-shadow:none;border:none;max-width:100%;padding:0;font-size:10pt;line-height:1.6}.exam-header{border-bottom:3px double #000;margin-bottom:0;padding-bottom:10px}.exam-title{font-size:18pt}.exam-school,.exam-subtitle{font-size:10pt}.exam-info-row{margin-bottom:14px;padding:6px 0 10px}.exam-problems-grid{column-count:2;column-rule:.5px solid #ccc;column-gap:18px}.exam-problem{break-inside:avoid;page-break-inside:avoid;-webkit-column-break-inside:avoid;width:100%;margin-bottom:2px;padding-bottom:10px;display:inline-block}.exam-problem-body{padding-left:16px;font-size:10pt;line-height:1.6}.exam-problem-num{font-size:12pt}.exam-problem-points{font-size:8pt}.exam-answer-box{-webkit-print-color-adjust:exact;print-color-adjust:exact;margin-top:6px;padding:6px 10px;font-size:9pt;background:#f5f5f5!important}.exam-choices{gap:4px;margin-top:4px}.katex{font-size:1em!important}}.tab-bar{border-bottom:1px solid var(--border);gap:0;margin-bottom:24px;display:flex}.tab-item{color:var(--text-muted);cursor:pointer;transition:all var(--transition);-webkit-user-select:none;user-select:none;border-bottom:2px solid #0000;margin-bottom:-1px;padding:10px 20px;font-size:14px;font-weight:500}.tab-item:hover{color:var(--text-secondary)}.tab-item.active{color:var(--accent);border-bottom-color:var(--accent)}.transform-options{background:var(--bg-subtle);border:1px solid var(--border);border-radius:var(--radius);grid-template-columns:repeat(auto-fill,minmax(220px,1fr));gap:12px;margin-bottom:24px;padding:20px;display:grid}.checkbox-label{cursor:pointer;color:var(--text-secondary);align-items:center;gap:8px;font-size:14px;display:flex}.checkbox-label input[type=checkbox]{accent-color:var(--accent);width:16px;height:16px}.item-renderer{line-height:1.8}.item-renderer--compact{line-height:1.9}.item-text-paragraph{text-indent:0;margin:6px 0;padding:0}.item-text-block{display:inline}.item-math-block{text-align:center;margin:12px 0}.item-blank{border-bottom:2px solid var(--text-primary);min-width:60px;margin:0 4px;display:inline-block}.item-figure-placeholder,.item-table-placeholder{text-align:center;color:var(--text-muted);border:1px dashed var(--border);border-radius:var(--radius);margin:12px 0;padding:24px;font-size:14px}.item-box{border:1px solid var(--border-strong);border-radius:var(--radius);margin:12px 0;padding:12px 16px}.choices-renderer{grid-template-columns:1fr;gap:4px 24px;margin-top:10px;display:grid}.choices-renderer.choices-cols-5{grid-template-columns:repeat(5,1fr)}.choices-renderer.choices-cols-2{grid-template-columns:repeat(2,1fr)}.choices-renderer.choices-cols-1{grid-template-columns:1fr}.choice-item{align-items:baseline;gap:6px;font-size:15px;line-height:1.8;display:flex}.choice-label{color:var(--text-secondary);flex-shrink:0}.choice-content{display:inline}.statements-renderer{border:1px solid var(--border-strong);border-radius:var(--radius);margin:12px 0;padding:12px 16px}.statement-item{text-align:left;align-items:baseline;gap:8px;line-height:1.8;display:flex}.statement-label{color:var(--text-primary);flex-shrink:0;font-weight:600}.statement-content{display:inline}@media (max-width:768px){.site-header{padding:0 16px}.main-container{padding:24px 16px}.json-editor-panel{grid-template-columns:1fr}.json-editor-left{border-right:none;border-bottom:1px solid var(--border)}.form-row{grid-template-columns:1fr}.exam-sheet{padding:24px}.step-item{padding:10px 16px;font-size:13px}}