:root{--bg: #FAFBFD;--card: #FFFFFF;--ink: #101A28;--muted: #46536A;--line: #E4E8F0;--primary: #2159C5;--primary-soft: #E5EDFB;--amber: #B9772A;--teal: #0E8C86;--rose: #B4463C;--radius: 14px;--shadow: 0 1px 3px rgba(16, 26, 40, .06), 0 4px 14px rgba(16, 26, 40, .05);--code-bg: #F1F4F9;--ink-faint: #7B8798}@media(prefers-color-scheme:dark){:root{--bg: #0B1017;--card: #131A24;--ink: #E8EDF4;--muted: #A4B0C0;--line: #263140;--primary: #6AA0F0;--primary-soft: #172A44;--shadow: 0 1px 3px rgba(0, 0, 0, .35), 0 4px 14px rgba(0, 0, 0, .25);--code-bg: #161E28;--ink-faint: #74808F}}*{box-sizing:border-box;margin:0;padding:0}html,body,#root{height:100%}body{background:var(--bg);color:var(--ink);font-family:Pretendard,Apple SD Gothic Neo,Malgun Gothic,system-ui,sans-serif;font-size:15px;line-height:1.6;-webkit-font-smoothing:antialiased}a{color:var(--primary);text-decoration:none}.container{max-width:960px;margin:0 auto;padding:24px 20px 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12px}.course-complete-label{order:-1;flex-basis:100%;white-space:normal}.course-complete-bar .btn{flex:1;justify-content:center;font-size:13px;padding:8px 10px}}.diagram{width:100%;height:auto;display:block;margin:4px 0}.card-completed{border-color:color-mix(in srgb,var(--teal) 45%,transparent)}.fold summary{cursor:pointer;font-size:13.5px;font-weight:700;color:var(--primary);list-style:none;-webkit-user-select:none;user-select:none}.fold summary:before{content:"▸ "}.fold[open] summary:before{content:"▾ "}.fold[open] summary{margin-bottom:10px}.success-text{color:var(--teal);font-size:14px;margin-top:10px}.is-selected{background:var(--primary-soft)}.lang-badge{display:inline-block;padding:2px 8px;border-radius:999px;font-size:12px;font-weight:600;border:1px solid var(--line)}.lang-badge--js{background:color-mix(in srgb,var(--amber) 12%,transparent);color:var(--amber)}.lang-badge--java{background:color-mix(in srgb,var(--primary) 12%,transparent);color:var(--primary)}.lang-badge--sql{background:color-mix(in srgb,var(--teal) 12%,transparent);color:var(--teal)}.sql-table{width:100%;border-collapse:collapse;font-size:13.5px}.sql-table th,.sql-table td{border:1px solid var(--line);padding:6px 10px;text-align:left}.sql-table th{background:var(--surface-2, var(--primary-soft));font-weight:700}.sql-setup{margin-top:10px;padding:12px;border:1px solid var(--line);border-radius:8px;background:var(--surface-2, var(--primary-soft));font-size:12.5px;line-height:1.6;overflow-x:auto;white-space:pre}.status-badge{display:inline-block;padding:2px 8px;border-radius:999px;font-size:12px;font-weight:600;border:1px solid var(--line);color:var(--muted)}.status-badge--passed{background:color-mix(in srgb,var(--teal) 14%,transparent);color:var(--teal);border-color:transparent}.status-badge--submitted{background:color-mix(in srgb,var(--amber) 14%,transparent);color:var(--amber);border-color:transparent}.status-badge--reviewed{background:var(--primary-soft);color:var(--primary);border-color:transparent}.coding-list{display:grid;gap:10px}.coding-item{display:flex;align-items:center;justify-content:space-between;gap:12px;text-decoration:none;color:inherit}.coding-item:hover{border-color:var(--primary)}.coding-item__main{display:flex;align-items:center;gap:14px;min-width:0}.coding-item__no{font-variant-numeric:tabular-nums;color:var(--ink-faint);font-weight:700}.coding-item__title{font-weight:600;margin-bottom:4px}.coding-item__meta{display:flex;align-items:center;gap:8px}.coding-item__difficulty{font-size:12px;color:var(--muted)}.coding-item__status{display:flex;align-items:center;gap:10px;flex-shrink:0}.coding-item__score{font-size:13px;font-variant-numeric:tabular-nums;color:var(--muted)}.coding-description{white-space:pre-wrap;line-height:1.7;margin:0}.coding-actions{display:flex;gap:8px;margin-top:12px;flex-wrap:wrap}.feedback-card{border-left:3px solid var(--primary)}.code-editor{display:flex;border:1px solid var(--line);border-radius:10px;overflow:hidden;background:var(--code-bg);font-family:ui-monospace,SFMono-Regular,Menlo,Consolas,monospace;font-size:13px;line-height:1.6}.code-editor__gutter{padding:12px 8px 12px 12px;text-align:right;color:var(--ink-faint);-webkit-user-select:none;user-select:none;overflow:hidden;border-right:1px solid var(--line);min-width:42px}.code-editor__area{flex:1;border:0;outline:none;resize:vertical;padding:12px;background:transparent;color:var(--ink);font:inherit;line-height:inherit;-moz-tab-size:2;tab-size:2;white-space:pre;overflow-wrap:normal;overflow-x:auto}.code-view{background:var(--code-bg);border:1px solid var(--line);border-radius:10px;padding:12px;overflow-x:auto;font-family:ui-monospace,SFMono-Regular,Menlo,Consolas,monospace;font-size:13px;line-height:1.6;margin:0 0 12px}.test-results{list-style:none;padding:0;margin:0;display:grid;gap:6px}.test-results li{display:flex;align-items:center;gap:10px;flex-wrap:wrap;padding:8px 10px;border-radius:8px;border:1px solid var(--line);font-size:14px}.test--pass{background:color-mix(in srgb,var(--teal) 8%,transparent)}.test--fail{background:color-mix(in srgb,var(--rose) 8%,transparent)}.test__mark{font-size:12px;font-weight:700;flex-shrink:0;padding:1px 7px;border-radius:999px}.test--pass .test__mark{background:var(--teal);color:#fff}.test--fail .test__mark{background:var(--rose);color:#fff}.test__name{flex:1;min-width:0}.test__detail{font-size:12px;color:var(--muted)}.test__detail code{background:var(--code-bg);padding:1px 5px;border-radius:4px}.ok{color:var(--teal)}.ng{color:var(--rose)}