:root{--bg-primary: #0d1117;--bg-secondary: #161b22;--bg-tertiary: #21262d;--text-primary: #f0f6fc;--text-secondary: #8b949e;--accent: #58a6ff;--accent-hover: #79b8ff;--success: #3fb950;--border: #30363d;--shadow: rgba(0, 0, 0, .4)}*{margin:0;padding:0;box-sizing:border-box}body{font-family:Inter,-apple-system,BlinkMacSystemFont,Segoe UI,sans-serif;background:var(--bg-primary);color:var(--text-primary);min-height:100vh;overflow:hidden}#app{display:flex;height:100vh}#controls{width:320px;min-width:320px;background:var(--bg-secondary);border-right:1px solid var(--border);padding:24px;overflow-y:auto;display:flex;flex-direction:column;gap:16px}#controls h1{font-size:1.5rem;font-weight:600;background:linear-gradient(135deg,var(--accent),#a371f7);-webkit-background-clip:text;-webkit-text-fill-color:transparent;background-clip:text;margin-bottom:8px}#controls h2{font-size:.875rem;font-weight:500;color:var(--text-secondary);text-transform:uppercase;letter-spacing:.05em;padding-bottom:8px;border-bottom:1px solid var(--border)}.unit-toggle{display:flex;gap:4px;background:var(--bg-tertiary);padding:4px;border-radius:8px;width:fit-content}.unit-btn{padding:6px 16px;border:none;border-radius:6px;background:transparent;color:var(--text-secondary);font-size:.875rem;font-weight:500;cursor:pointer;transition:all .15s}.unit-btn.active{background:var(--accent);color:#fff}.unit-btn:hover:not(.active){background:var(--border);color:var(--text-primary)}.input-row{display:flex;align-items:center;gap:10px}.input-row input[type=range]{flex:1}.num-input{width:70px;padding:6px 8px;border:1px solid var(--border);border-radius:6px;background:var(--bg-tertiary);color:var(--text-primary);font-size:.875rem;font-weight:600;text-align:right}.num-input:focus{outline:none;border-color:var(--accent);box-shadow:0 0 0 2px #58a6ff33}.num-input::-webkit-inner-spin-button,.num-input::-webkit-outer-spin-button{-webkit-appearance:none;margin:0}.num-input{-moz-appearance:textfield;-webkit-appearance:textfield;appearance:textfield}.unit{font-size:.75rem;color:var(--text-secondary);min-width:24px}.control-group{display:flex;flex-direction:column;gap:8px}.control-group label{font-size:.875rem;color:var(--text-secondary);display:flex;justify-content:space-between;align-items:center}.control-group.checkbox label{flex-direction:row;gap:10px;cursor:pointer;color:var(--text-primary)}.control-group input[type=range]{-webkit-appearance:none;-moz-appearance:none;appearance:none;width:100%;height:6px;background:var(--bg-tertiary);border-radius:3px;outline:none;cursor:pointer}.control-group input[type=range]::-webkit-slider-thumb{-webkit-appearance:none;-moz-appearance:none;appearance:none;width:18px;height:18px;background:var(--accent);border-radius:50%;cursor:pointer;transition:transform .15s,box-shadow .15s}.control-group input[type=range]::-webkit-slider-thumb:hover{transform:scale(1.1);box-shadow:0 0 0 4px #58a6ff33}.control-group input[type=checkbox]{width:18px;height:18px;accent-color:var(--accent);cursor:pointer}.control-group .value{font-size:.875rem;font-weight:600;color:var(--accent);min-width:40px;text-align:right}.toggle-group{display:flex;gap:4px;background:var(--bg-tertiary);padding:3px;border-radius:6px}.toggle-btn{flex:1;padding:6px 12px;background:transparent;color:var(--text-secondary);border:none;border-radius:4px;font-size:.85rem;font-weight:500;cursor:pointer;transition:all .2s}.toggle-btn:hover{background:#ffffff0d}.toggle-btn.active{background:var(--accent);color:#fff}.tag-options{padding-left:12px;border-left:2px solid var(--bg-tertiary);margin-left:8px}.actions{margin-top:auto;padding-top:16px;display:flex;flex-direction:column;gap:10px}.split-btn-group{position:relative;display:flex;border-radius:8px;overflow:visible}.split-btn-main{flex:1;display:flex;align-items:center;justify-content:center;gap:8px;padding:12px 16px;background:linear-gradient(135deg,var(--accent),#a371f7);color:#fff;border:none;border-radius:8px 0 0 8px;font-size:.9rem;font-weight:600;cursor:pointer;transition:opacity .15s,transform .15s}.split-btn-main:hover{opacity:.9}.split-btn-main:disabled{opacity:.5;cursor:not-allowed}.split-btn-arrow{display:flex;align-items:center;justify-content:center;width:36px;background:linear-gradient(135deg,#4a94e8,#9363e0);color:#fff;border:none;border-left:1px solid rgba(255,255,255,.2);border-radius:0 8px 8px 0;cursor:pointer;transition:opacity .15s}.split-btn-arrow:hover{opacity:.85}.slicer-btn{flex:1;display:flex;align-items:center;justify-content:center;gap:8px;padding:12px 16px;background:var(--bg-tertiary);color:var(--text-primary);border:1px solid var(--border);border-right:none;border-radius:8px 0 0 8px;font-size:.9rem;font-weight:500;cursor:pointer;transition:background .15s,border-color .15s}.slicer-btn:hover{background:var(--border);border-color:var(--text-secondary)}.slicer-arrow{background:var(--bg-tertiary);color:var(--text-secondary);border:1px solid var(--border);border-left:none}.slicer-arrow:hover{background:var(--border)}.dropdown-menu{display:none;position:absolute;bottom:calc(100% + 6px);left:0;right:0;background:var(--bg-secondary);border:1px solid var(--border);border-radius:8px;padding:4px;box-shadow:0 8px 24px #0006;z-index:100}.dropdown-menu.open{display:block}.dropdown-item{display:flex;align-items:center;gap:8px;width:100%;padding:10px 12px;background:none;color:var(--text-primary);border:none;border-radius:6px;font-size:.875rem;font-weight:500;cursor:pointer;text-align:left;transition:background .1s}.dropdown-item:hover{background:var(--bg-tertiary)}.dropdown-item.active{color:var(--accent)}.dropdown-item.active:after{content:"✓";margin-left:auto;font-size:.75rem}#status{font-size:.75rem;color:var(--text-secondary);text-align:center;padding:8px;background:var(--bg-tertiary);border-radius:6px}#status.loading{color:var(--accent)}#status.ready{color:var(--success)}#status.error{color:#f85149}#viewer-container{flex:1;position:relative;background:linear-gradient(180deg,var(--bg-primary) 0%,#1a1f26 100%)}#viewer-container canvas{display:block}.loading-overlay{position:absolute;top:0;right:0;bottom:0;left:0;display:flex;align-items:center;justify-content:center;background:#0d1117cc;-webkit-backdrop-filter:blur(4px);backdrop-filter:blur(4px)}.spinner{width:48px;height:48px;border:3px solid var(--border);border-top-color:var(--accent);border-radius:50%;animation:spin 1s linear infinite}@keyframes spin{to{transform:rotate(360deg)}}.dimension-label{background:transparent;color:#fff;padding:0;border-radius:0;font-size:12px;font-weight:500;font-family:Inter,-apple-system,BlinkMacSystemFont,sans-serif;white-space:nowrap;text-shadow:0 1px 3px rgba(0,0,0,.8);pointer-events:none;-webkit-user-select:none;user-select:none}.dimension-label.secondary{background:#8b949ed9;font-size:10px}.help-overlay{position:absolute;bottom:10px;right:10px;background:#0006;padding:8px 12px;border-radius:6px;color:var(--text-secondary);font-size:.75rem;font-family:Inter,-apple-system,BlinkMacSystemFont,sans-serif;pointer-events:none;-webkit-user-select:none;user-select:none;z-index:10;display:flex;flex-direction:column;gap:4px;text-align:right;-webkit-backdrop-filter:blur(2px);backdrop-filter:blur(2px);border:1px solid rgba(255,255,255,.05)}.help-item{display:flex;justify-content:flex-end;gap:8px;width:100%}.help-item .key{font-weight:600;color:var(--text-primary);opacity:.9}