:root {
  --primary: #0EA5E9; --primary-hover: #0284C7; --secondary: #38BDF8;
  --accent: #F59E0B; --success: #10B981; --error: #EF4444;
  --bg: #0B1120; --bg-elevated: #111827; --bg-card: #1C2536;
  --bg-input: #0B1120; --text: #E0F2FE; --text-muted: #7DD3FC; --text-dim: #475569;
  --border: #1E293B; --border-hover: #334155; --radius: 12px; --radius-sm: 8px;
  --font: 'Inter', system-ui, sans-serif; --mono: monospace; --transition: 200ms ease;
}
*,*::before,*::after{box-sizing:border-box;margin:0;padding:0}
body{font-family:var(--font);background:var(--bg);color:var(--text);min-height:100vh;overflow:hidden}
.app{display:flex;flex-direction:column;height:100vh}

.header{display:flex;align-items:center;justify-content:space-between;padding:12px 20px;background:var(--bg-elevated);border-bottom:1px solid var(--border);gap:12px;flex-shrink:0;flex-wrap:wrap}
.header-left{display:flex;align-items:center;gap:12px}
.logo{font-size:1.3rem}
.header-title{font-size:1.05rem;font-weight:700;background:linear-gradient(135deg,var(--primary),var(--secondary));-webkit-background-clip:text;-webkit-text-fill-color:transparent;background-clip:text}
.header-right{display:flex;gap:8px;align-items:center}

.btn{display:inline-flex;align-items:center;gap:6px;padding:8px 14px;font-size:.8rem;font-weight:500;font-family:var(--font);border:none;border-radius:var(--radius-sm);cursor:pointer;transition:all var(--transition);white-space:nowrap}
.btn-primary{background:linear-gradient(135deg,var(--primary),var(--primary-hover));color:#fff;box-shadow:0 2px 8px rgba(14,165,233,.3)}
.btn-primary:hover{transform:translateY(-1px);box-shadow:0 4px 16px rgba(14,165,233,.4)}
.btn-ghost{background:transparent;color:var(--text-muted);border:1px solid var(--border)}
.btn-ghost:hover{background:var(--bg-card);color:var(--text);border-color:var(--border-hover)}
.btn-sm{padding:5px 10px;font-size:.72rem}

.main{display:grid;grid-template-columns:320px 1fr;flex:1;overflow:hidden;gap:1px;background:var(--border)}
.controls-panel{background:var(--bg);padding:14px;display:flex;flex-direction:column;gap:12px;overflow-y:auto}
.preview-panel{background:var(--bg);display:flex;flex-direction:column;align-items:center;justify-content:center;gap:12px;padding:20px;overflow:hidden}

.presets{display:flex;gap:4px;flex-wrap:wrap;align-items:center}
.presets-label{font-size:.65rem;font-weight:600;color:var(--text-dim)}
.preset-btn{padding:3px 8px;font-size:.6rem;font-family:var(--font);background:var(--bg-card);border:1px solid var(--border);border-radius:6px;color:var(--text-muted);cursor:pointer;transition:all var(--transition)}
.preset-btn:hover{border-color:var(--primary);color:var(--text)}

.sliders{display:flex;flex-direction:column;gap:8px}
.slider-group{display:flex;flex-direction:column;gap:2px}
.slider-header{display:flex;justify-content:space-between;align-items:center}
.slider-label{font-size:.68rem;font-weight:500;color:var(--text-muted)}
.slider-value{font-size:.65rem;font-weight:600;color:var(--secondary)}
.slider-reset{font-size:.5rem;cursor:pointer;color:var(--text-dim);background:none;border:none;padding:2px 4px}
.slider-reset:hover{color:var(--accent)}
input[type="range"]{width:100%;height:4px;appearance:none;background:var(--border);border-radius:2px;outline:none;cursor:pointer}
input[type="range"]::-webkit-slider-thumb{appearance:none;width:14px;height:14px;border-radius:50%;background:var(--primary);border:2px solid var(--bg);box-shadow:0 0 6px rgba(14,165,233,.4);cursor:pointer}

.preview-area{max-width:100%;max-height:60vh;border-radius:var(--radius);overflow:hidden;position:relative}
.preview-img{max-width:100%;max-height:55vh;display:block;border-radius:var(--radius);transition:filter .3s ease}

.css-output{margin-top:auto}
.css-label{font-size:.65rem;font-weight:600;color:var(--text-dim);margin-bottom:4px;display:block}
.code-block{padding:10px;font-family:var(--mono);font-size:.68rem;line-height:1.5;background:var(--bg-input);border:1px solid var(--border);border-radius:var(--radius-sm);color:var(--accent);overflow-x:auto;white-space:pre-wrap}

.upload-btn{display:inline-flex;cursor:pointer}

.toast{position:fixed;bottom:24px;left:50%;transform:translateX(-50%);padding:10px 20px;background:var(--bg-card);border:1px solid var(--primary);border-radius:var(--radius-sm);color:var(--secondary);font-size:.8rem;font-weight:500;z-index:200;animation:toast-in .3s ease}
@keyframes toast-in{from{opacity:0;transform:translateX(-50%) translateY(10px)}to{opacity:1;transform:translateX(-50%) translateY(0)}}
::-webkit-scrollbar{width:6px}::-webkit-scrollbar-track{background:transparent}::-webkit-scrollbar-thumb{background:var(--border);border-radius:3px}
@media(max-width:768px){.main{grid-template-columns:1fr;grid-template-rows:auto 1fr}}