:root{--bg-primary:#f8f9fa;--bg-panel:#fff;--border-color:#dee2e6;--text-primary:#212529;--text-secondary:#6c757d;--accent:#06c;--accent-hover:#0052a3;--success:#28a745;--error:#dc3545;--font-ui:-apple-system,BlinkMacSystemFont,"Segoe UI","Roboto",sans-serif;--font-mono:"SF Mono","Monaco","Cascadia Code","Courier New",monospace}*{box-sizing:border-box;margin:0;padding:0}body{font-family:var(--font-ui);background:var(--bg-primary);color:var(--text-primary);display:flex;flex-direction:column;height:100vh;line-height:1.6}header{background:var(--bg-panel);border-bottom:1px solid var(--border-color);padding:1.5rem 2rem}header h1{margin-bottom:.25rem;font-size:1.75rem}header p{color:var(--text-secondary);margin-bottom:.5rem;font-size:.95rem}.header-links a{color:var(--accent);text-decoration:none;margin-right:1rem;font-size:.9rem}.header-links a:hover{text-decoration:underline}main{display:grid;grid-template-columns:2fr 1.5fr 1.5fr;overflow:hidden;flex:1;gap:0}.panel{background:var(--bg-panel);border-right:1px solid var(--border-color);display:flex;overflow:hidden;flex-direction:column}.panel:last-child{border-right:none}.panel-header{border-bottom:1px solid var(--border-color);display:flex;background:#fafbfc;justify-content:space-between;align-items: center;padding:1rem 1.25rem}.panel-header h2{text-transform:uppercase;letter-spacing:.05em;color:var(--text-secondary);font-size:.875rem;font-weight:600}.panel-content{overflow:auto;position:relative;flex:1}#editor{height:100%;font-size:14px}.cm-editor{height:100%}.cm-scroller{font-family:var(--font-mono)}.controls{border-top:1px solid var(--border-color);display:flex;background:#fafbfc;align-items: center;gap:.75rem;padding:1rem 1.25rem}select{border:1px solid var(--border-color);font-family:var(--font-ui);cursor:pointer;background:#fff;border-radius:4px;flex:1;padding:.5rem .75rem;font-size:.875rem}select:focus{outline:none;border-color:var(--accent)}button{background:var(--accent);color:#fff;font-family:var(--font-ui);cursor:pointer;border:none;border-radius:4px;padding:.5rem 1.25rem;transition:background .2s;font-size:.875rem;font-weight:500}button:hover{background:var(--accent-hover)}button:active{transform:translateY(1px)}textarea{font-family:var(--font-mono);resize:none;background:var(--bg-panel);border:none;width:100%;height:100%;padding:1rem;font-size:14px}textarea:focus{outline:none}#output{font-family:var(--font-mono);white-space:pre-wrap;word-wrap:break-word;padding:1rem;font-size:14px}#output.success{color:var(--success)}#output.error{color:var(--error)}footer{background:var(--bg-panel);border-top:1px solid var(--border-color);text-align:center;color:var(--text-secondary);padding:.75rem 2rem;font-size:.85rem}footer a{color:var(--accent);text-decoration:none}footer a:hover{text-decoration:underline}@media (max-width:1024px){main{grid-template-columns:1fr 1fr 1fr}}@media (max-width:768px){main{grid-template-columns:1fr;grid-template-rows:2fr 1fr 1fr}.panel{border-right:none;border-bottom:1px solid var(--border-color)}.panel:last-child{border-bottom:none}}.shortcut-hint{color:var(--text-secondary);font-size:.75rem;font-family:var(--font-mono)}