@import url('https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600;700;800&display=swap');
*,*::before,*::after{box-sizing:border-box;margin:0;padding:0}
:root{--primary:#667EEA;--accent:#764BA2;--bg:#0F172A;--surface:#1E293B;--surface2:#334155;--text:#E2E8F0;--text-dim:#94A3B8;--border:#334155;--radius:12px;--font:'Inter',system-ui,sans-serif}
html{font-family:var(--font);background:var(--bg);color:var(--text);line-height:1.6}
body{min-height:100vh;display:flex;flex-direction:column}
.header{padding:.6rem 1rem;display:flex;align-items:center;justify-content:space-between;border-bottom:1px solid var(--border);flex-wrap:wrap;gap:.4rem}
.header h1{font-size:.95rem;font-weight:800;background:linear-gradient(135deg,var(--primary),var(--accent));-webkit-background-clip:text;-webkit-text-fill-color:transparent}
.header-actions{display:flex;gap:.3rem;align-items:center;flex-wrap:wrap}
.btn{padding:.3rem .6rem;border-radius:8px;font-size:.7rem;font-weight:600;cursor:pointer;border:none;transition:all .15s;font-family:var(--font)}
.btn-ghost{background:transparent;border:1px solid var(--border);color:var(--text-dim)}.btn-ghost:hover{background:var(--surface2);color:var(--text)}
.select-sm{padding:.3rem .4rem;border-radius:6px;border:1px solid var(--border);background:var(--surface);color:var(--text);font-size:.7rem;font-family:var(--font);outline:none}
.main{flex:1;display:grid;grid-template-columns:1fr 1fr;gap:0;overflow:hidden}
.panel-header{padding:.35rem .75rem;background:var(--surface);border-bottom:1px solid var(--border);font-size:.7rem;font-weight:700;color:var(--text-dim);display:flex;justify-content:space-between;align-items:center}
.editor-panel{display:flex;flex-direction:column;border-right:1px solid var(--border)}
.editor{flex:1;padding:.5rem;background:var(--bg);color:var(--text);font-family:'Courier New',monospace;font-size:.75rem;border:none;outline:none;resize:none;line-height:1.5;tab-size:2;white-space:pre}
.vars-bar{padding:.35rem .5rem;border-top:1px solid var(--border);display:flex;gap:.3rem;align-items:center;flex-wrap:wrap;background:var(--surface)}
.vars-label{font-size:.65rem;font-weight:700;color:var(--text-dim)}
.var-inp{padding:.2rem .4rem;border-radius:4px;border:1px solid var(--border);background:var(--surface2);color:var(--text);font-size:.7rem;width:90px;outline:none;font-family:var(--font)}
.preview-panel{display:flex;flex-direction:column}
.preview-container{flex:1;display:flex;justify-content:center;align-items:start;padding:.5rem;overflow:auto;background:#E5E7EB}
.preview-container.dark{background:#1a1a2e}
#preview-frame{border:none;height:100%;background:#fff;box-shadow:0 2px 16px rgba(0,0,0,.15);border-radius:4px;transition:width .3s}
.width-slider-wrap{padding:.3rem .75rem;border-top:1px solid var(--border);background:var(--surface)}
.slider{width:100%;appearance:none;background:var(--surface2);height:4px;border-radius:2px;outline:none}
.slider::-webkit-slider-thumb{appearance:none;width:14px;height:14px;border-radius:50%;background:var(--primary);cursor:pointer}
.width-display{font-size:.62rem;color:var(--primary);font-weight:600}
.toast{position:fixed;bottom:1.5rem;right:1.5rem;background:var(--surface);border:1px solid var(--primary);color:var(--primary);padding:.4rem .8rem;border-radius:8px;font-size:.72rem;z-index:200;transform:translateY(80px);opacity:0;transition:all .3s}
.toast.show{transform:translateY(0);opacity:1}
@media(max-width:768px){.main{grid-template-columns:1fr;grid-template-rows:1fr 1fr}.editor-panel{border-right:none;border-bottom:1px solid var(--border)}}