*,*:before,*:after{box-sizing:border-box;margin:0;padding:0}:root{--bg: #141518;--bg-panel: #1c1d21;--bg-raised: #242529;--bg-hover: #2c2d32;--border: rgba(255 255 255 / .1);--border-active: rgba(255 255 255 / .25);--text: #e8eaf0;--text-muted: rgba(232 234 240 / .55);--accent: #60a5fa;--accent-dim: rgba(96 165 250 / .18);--radius: 6px;--topbar-h: 52px;--tool-w: 188px;--canvas-display: 512px}body{background:var(--bg);color:var(--text);font-family:ui-sans-serif,system-ui,-apple-system,BlinkMacSystemFont,Segoe UI,sans-serif;font-size:13px;line-height:1.5;min-height:100vh}button,select,input{font:inherit;color:inherit}.app{display:flex;flex-direction:column;height:100vh;overflow:hidden}.app-main{flex:1;display:flex;gap:1px;background:var(--border);overflow:hidden}.topbar{flex-shrink:0;height:var(--topbar-h);display:flex;align-items:center;gap:16px;padding:0 16px;background:var(--bg-panel);border-bottom:1px solid var(--border);overflow-x:auto}.topbar-brand{display:flex;align-items:baseline;gap:8px;flex-shrink:0}.topbar-logo{font-size:11px;font-weight:700;text-transform:uppercase;letter-spacing:.1em;color:var(--accent)}.topbar-title{font-size:13px;font-weight:500;color:var(--text-muted)}.topbar-group{display:flex;align-items:center;gap:6px}.topbar-group--history,.topbar-group--actions{margin-left:auto}.topbar-group--actions{margin-left:0}.topbar-label{font-size:11px;color:var(--text-muted);white-space:nowrap}.topbar-select{padding:4px 8px;background:var(--bg-raised);border:1px solid var(--border);border-radius:var(--radius);cursor:pointer;-webkit-appearance:auto;-moz-appearance:auto;appearance:auto}.topbar-btn{height:30px;padding:0 12px;background:var(--bg-raised);border:1px solid var(--border);border-radius:var(--radius);cursor:pointer;white-space:nowrap;transition:background .15s,border-color .15s}.topbar-btn:hover{background:var(--bg-hover);border-color:var(--border-active)}.topbar-btn:disabled{opacity:.35;cursor:not-allowed}.topbar-btn--primary{background:var(--accent-dim);border-color:var(--accent);color:var(--accent)}.topbar-btn--primary:hover{background:#60a5fa47}.topbar-toggle{height:30px;padding:0 12px;background:var(--bg-raised);border:1px solid var(--border);border-radius:var(--radius);cursor:pointer;transition:background .15s,border-color .15s}.topbar-toggle--active{background:var(--accent-dim);border-color:var(--accent);color:var(--accent)}.tool-panel{width:var(--tool-w);flex-shrink:0;background:var(--bg-panel);overflow-y:auto;display:flex;flex-direction:column;gap:1px}.tool-section{padding:12px;background:var(--bg-panel);display:flex;flex-direction:column;gap:8px;border-bottom:1px solid var(--border)}.tool-section-title{font-size:10px;font-weight:700;text-transform:uppercase;letter-spacing:.08em;color:var(--text-muted)}.brush-grid{display:grid;grid-template-columns:1fr 1fr;gap:4px}.brush-btn{height:28px;padding:0 6px;background:var(--bg-raised);border:1px solid var(--border);border-radius:var(--radius);cursor:pointer;font-size:12px;text-align:center;white-space:nowrap;overflow:hidden;text-overflow:ellipsis;transition:background .1s,border-color .1s;display:flex;align-items:center;justify-content:center}.brush-btn:hover{background:var(--bg-hover);border-color:var(--border-active)}.brush-btn--active{background:var(--accent-dim);border-color:var(--accent);color:var(--accent)}.tool-slider{display:flex;flex-direction:column;gap:5px;cursor:default}.tool-slider-label{display:flex;justify-content:space-between;font-size:12px;color:var(--text-muted)}.tool-slider-value{font-variant-numeric:tabular-nums;color:var(--text)}.tool-slider input[type=range]{width:100%;accent-color:var(--accent);cursor:pointer}.tool-checkbox{display:flex;align-items:center;gap:6px;font-size:12px;cursor:pointer}.tool-checkbox input{accent-color:var(--accent);cursor:pointer}.paint-stage{position:relative;width:var(--canvas-display);height:var(--canvas-display);flex-shrink:0;background:repeating-conic-gradient(#1e2024,#1e2024 25%,#16181b 0%,#16181b 50%) 0 0 / 16px 16px;overflow:hidden;align-self:center;margin:auto}.paint-stage-ref{position:absolute;top:0;right:0;bottom:0;left:0;width:100%;height:100%;object-fit:cover;pointer-events:none;-webkit-user-select:none;user-select:none}.paint-stage-canvas{position:absolute;top:0;right:0;bottom:0;left:0;width:100%;height:100%;cursor:crosshair;display:block}.paint-stage-canvas--rgviz{filter:saturate(3) brightness(1.2)}.preview-panel{flex:1;min-width:0;background:var(--bg-panel);display:flex;flex-direction:column;overflow:hidden}.preview-viewport-wrap{flex:1;min-height:0;container-type:size;display:flex;align-items:center;justify-content:center;overflow:hidden}.preview-viewport{aspect-ratio:1 / 1;width:min(100cqw,100cqh);position:relative;background:#000;overflow:hidden}.preview-viewport>canvas{position:absolute!important;top:0!important;right:0!important;bottom:0!important;left:0!important;width:100%!important;height:100%!important}.preview-loading,.preview-error{position:absolute;top:0;right:0;bottom:0;left:0;display:flex;align-items:center;justify-content:center;font-size:12px;color:var(--text-muted)}.preview-error{color:#f87171}.preview-controls{flex-shrink:0;height:240px;overflow-y:auto;border-top:1px solid var(--border)}.preview-base-row{display:flex;flex-wrap:wrap;gap:4px}