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#00000026}.iso-info-wrapper{position:fixed;top:1rem;right:1rem;z-index:1000}.iso-info-trigger{width:36px;height:36px;border-radius:50%;border:1px solid rgba(255,255,255,.25);background:#ffffff1f;color:#fff;font-family:Georgia,Times New Roman,serif;font-size:1.2rem;font-style:italic;line-height:1;cursor:pointer;transition:background .15s ease,color .15s ease}.iso-info-trigger:hover{background:#fff;color:#1ca5bd}.drag-ghost{position:fixed;width:80px;height:80px;pointer-events:none;opacity:.75;z-index:2000}.toolbar{width:200px;background:#fffffff2;border-radius:15px;padding:15px;box-shadow:0 8px 32px #0003;overflow-y:auto}.toolbar h2{color:#333;margin-bottom:12px;font-size:1.2em;text-align:center}.blocks-container{display:flex;flex-direction:column;gap:8px}.toolbar-hint{font-size:.8em;color:#555;margin:-4px 0 10px;text-align:center;line-height:1.3}.block-item{width:100%;background:#fff;border:2px solid #ddd;border-radius:10px;padding:10px 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#0003;position:relative;overflow:hidden;touch-action:none;-webkit-user-select:none;user-select:none}.snap-alternative{position:absolute;width:16px;height:16px;border-radius:50%;background:#4ade80;border:2px solid #16a34a;cursor:pointer;z-index:900;animation:snap-pulse 1s ease-in-out infinite;transition:transform .15s ease}.snap-alternative:hover{transform:scale(1.4);background:#22c55e}@keyframes snap-pulse{0%,to{box-shadow:0 0 #4ade8099}50%{box-shadow:0 0 0 6px #4ade8000}}.snap-hint{position:absolute;bottom:8px;left:50%;transform:translate(-50%);background:#000000b3;color:#4ade80;font-size:.8em;padding:6px 14px;border-radius:8px;white-space:nowrap;z-index:950;pointer-events:none;animation:hint-fade-in .3s ease}@keyframes hint-fade-in{0%{opacity:0;transform:translate(-50%) translateY(4px)}to{opacity:1;transform:translate(-50%) translateY(0)}}.canvas.pannable{cursor:grab}.canvas.panning{cursor:grabbing}.canvas-hints{position:absolute;bottom:12px;left:14px;max-width:55%;display:flex;flex-direction:column;align-items:flex-start;gap:5px;pointer-events:none;-webkit-user-select:none;user-select:none}.canvas-hints span{font-size:.85em;color:#475569;background:#f1f5f9eb;border:1px solid #e2e8f0;border-radius:999px;padding:5px 14px}.controls{position:absolute;bottom:10px;right:10px;display:flex;gap:6px;z-index:100}.controls button{background:#ffffffe6;border:1.5px solid #1ca5bd;color:#1ca5bd;padding:6px 14px;border-radius:16px;font-size:.8em;font-weight:600;cursor:pointer;transition:all .2s ease;box-shadow:0 2px 8px #0000001a;white-space:nowrap}.controls button:hover{background:#1ca5bd;color:#fff;box-shadow:0 4px 12px #1ca5bd66}.controls button:active{transform:scale(.96)}.name-section{display:grid;grid-template-columns:1fr 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#c3e6cb}.feedback.incorrect{background:#f8d7da;color:#721c24;border:2px solid #f5c6cb}.challenge-panel{background:#fffffff2;border-radius:15px;padding:20px;box-shadow:0 4px 16px #0000001a;display:flex;flex-direction:column;gap:15px}.difficulty-bar{display:flex;align-items:center;gap:12px;flex-wrap:wrap}.difficulty-label{font-weight:600;color:#555;font-size:.95em}.difficulty-pills{display:flex;gap:6px}.pill{padding:6px 16px;border-radius:20px;border:2px solid #1ca5bd;background:#fff;color:#1ca5bd;font-size:.9em;font-weight:600;cursor:pointer;transition:all .2s ease}.pill:hover{background:#eaf6f9}.pill.active{background:#1ca5bd;color:#fff}.new-challenge-btn{margin-left:auto;padding:8px 20px;border-radius:20px;border:2px solid #17879b;background:#17879b;color:#fff;font-size:.9em;font-weight:600;cursor:pointer;transition:all .2s ease}.new-challenge-btn:hover{background:#5a3780;transform:translateY(-1px);box-shadow:0 4px 12px #17879b4d}.challenge-task{text-align:center}.task-instruction{font-size:1.1em;font-weight:600;color:#333}.target-name{font-size:1.8em;font-weight:700;color:#1ca5bd;margin:8px 0}.task-hint{font-size:.95em;color:#888}.challenge-action{display:flex;justify-content:center}.name-input-row{display:flex;gap:10px;align-items:center;flex-wrap:wrap;justify-content:center}.name-input-row input{padding:10px 16px;font-size:1.1em;border:2px solid #ddd;border-radius:8px;min-width:220px}.name-input-row input:focus{outline:none;border-color:#1ca5bd}.check-btn{padding:10px 24px;border-radius:25px;border:none;background:#1ca5bd;color:#fff;font-size:1em;font-weight:600;cursor:pointer;transition:all .2s ease}.check-btn:hover{background:#17879b;transform:translateY(-1px)}.solution-btn{padding:10px 20px;border-radius:25px;border:2px solid #f59e0b;background:#fff;color:#b45309;font-size:.9em;font-weight:600;cursor:pointer;transition:all .2s ease}.solution-btn:hover{background:#fef3c7}.challenge-feedback{text-align:center;padding:12px 20px;border-radius:10px;font-weight:600;font-size:1em}.challenge-feedback.correct{background:#d4edda;color:#155724;border:2px solid #c3e6cb}.challenge-feedback.incorrect{background:#f8d7da;color:#721c24;border:2px solid #f5c6cb}.isomer-progress{display:flex;flex-direction:column;gap:10px}.progress-header{display:flex;align-items:center;gap:12px;font-weight:600;color:#555;font-size:.95em}.progress-bar{flex:1;height:10px;background:#e5e7eb;border-radius:5px;overflow:hidden}.progress-fill{height:100%;background:linear-gradient(90deg,#1ca5bd,#17879b);border-radius:5px;transition:width .4s ease}.found-list{display:flex;flex-wrap:wrap;gap:8px}.found-tag{display:inline-block;padding:5px 14px;border-radius:20px;background:#d4edda;color:#155724;font-size:.9em;font-weight:600;border:1px solid #c3e6cb}.challenge-solution{text-align:center;padding:12px 20px;border-radius:10px;background:#e8f4fd;color:#1e5f8b;border:2px solid #b6d4ea;font-size:1em}.kim-info-backdrop{position:fixed;inset:0;background:#0f172a80;display:flex;align-items:center;justify-content:center;z-index:10000;padding:1rem;font-family:var(--font-body, "IBM Plex Sans", system-ui, -apple-system, sans-serif)}.kim-info-card{background:var(--surface, #ffffff);border:1px solid var(--border, #e2e8f0);border-radius:var(--radius-lg, 12px);box-shadow:0 12px 30px #0003;padding:1.5rem;max-width:560px;width:100%;max-height:calc(100vh - 2rem);overflow-y:auto;color:var(--ink, #1a1a1a)}.kim-info-header{display:flex;align-items:flex-start;justify-content:space-between;gap:1rem;margin-bottom:1rem}.kim-info-title{margin:0;font-family:var(--font-display, "Instrument Serif", Georgia, serif);font-size:1.75rem;font-weight:400;line-height:1.2;color:var(--ink, #1a1a1a)}.kim-info-close{background:transparent;border:1px solid var(--border, #e2e8f0);color:var(--ink-soft, #475569);width:32px;height:32px;border-radius:var(--radius, 8px);font-size:1.4rem;line-height:1;cursor:pointer;flex-shrink:0;transition:background .15s ease,color .15s ease}.kim-info-close:hover{background:var(--surface-soft, #f8fafc);color:var(--ink, #1a1a1a)}.kim-info-close:focus-visible{outline:2px solid var(--cyan, #06b6d4);outline-offset:2px}.kim-info-section{margin-top:1rem}.kim-info-section:first-of-type{margin-top:0}.kim-info-section-title{margin:0 0 .5rem;font-family:var(--font-body, "IBM Plex Sans", system-ui, sans-serif);font-size:.85rem;font-weight:600;text-transform:uppercase;letter-spacing:.06em;color:var(--cyan-light, #1ca5bd)}.kim-info-list{margin:0;padding-left:1.25rem;font-size:.95rem;line-height:1.55;color:var(--ink, #1a1a1a)}.kim-info-list li{margin-bottom:.4rem}.kim-info-list li:last-child{margin-bottom:0}.kim-info-list strong{font-weight:600}.kim-info-bubble{position:absolute;top:calc(100% + 10px);right:0;z-index:9000;background:var(--ink, #1a1a1a);color:#fff;font-family:var(--font-body, "IBM Plex Sans", system-ui, -apple-system, sans-serif);font-size:.85rem;line-height:1.35;padding:.55rem .8rem;border-radius:var(--radius, 8px);box-shadow:0 6px 18px #0000002e;max-width:240px;cursor:pointer;animation:kim-info-bubble-in .22s ease-out}.kim-info-bubble-caret{position:absolute;top:-5px;right:10px;width:10px;height:10px;background:var(--ink, #1a1a1a);transform:rotate(45deg);border-radius:1px}@keyframes kim-info-bubble-in{0%{opacity:0;transform:translateY(-6px)}to{opacity:1;transform:translateY(0)}}