:root{--bg: #fafafa;--surface: #ffffff;--text: #1a1a1a;--text-secondary: #666;--accent: #2563eb;--accent-hover: #1d4ed8;--border: #e0e0e0;--error: #dc2626;--radius: 8px}@media(prefers-color-scheme:dark){:root{--bg: #0a0a0a;--surface: #141414;--text: #e5e5e5;--text-secondary: #888;--accent: #3b82f6;--accent-hover: #60a5fa;--border: #2a2a2a;--error: #ef4444}}*{margin:0;padding:0;box-sizing:border-box}body{font-family:-apple-system,BlinkMacSystemFont,Segoe UI,system-ui,sans-serif;background:var(--bg);color:var(--text);max-width:600px;margin:0 auto;padding:48px 20px;line-height:1.5}header{margin-bottom:32px}h1{font-size:1.5rem;font-weight:600;letter-spacing:-.02em}.subtitle{color:var(--text-secondary);font-size:.875rem;margin-top:4px}#drop-zone{border:2px dashed var(--border);border-radius:var(--radius);padding:48px 24px;text-align:center;cursor:pointer;transition:border-color .15s,background-color .15s}#drop-zone:hover,#drop-zone.drag-over{border-color:var(--accent);background-color:#2563eb0a}.drop-label{font-size:.9375rem;color:var(--text-secondary)}.drop-or{font-size:.8125rem;color:var(--text-secondary);margin:8px 0}button{display:inline-flex;align-items:center;padding:8px 16px;background:var(--accent);color:#fff;border:none;border-radius:var(--radius);cursor:pointer;font-size:.875rem;font-family:inherit;transition:background .15s}button:hover{background:var(--accent-hover)}#controls{margin-top:20px;padding:16px;background:var(--surface);border:1px solid var(--border);border-radius:var(--radius)}.control-row{margin-bottom:12px}.control-heading{display:block;font-size:.875rem;color:var(--text-secondary);margin-bottom:8px}.quality-options{display:grid;gap:8px}.quality-option{display:grid;grid-template-columns:16px minmax(0,1fr);column-gap:10px;row-gap:2px;align-items:center;padding:8px 10px;border:1px solid var(--border);border-radius:var(--radius);cursor:pointer;transition:border-color .15s,background-color .15s}.quality-option:hover{border-color:var(--accent)}.quality-option input{margin:0;accent-color:var(--accent)}.quality-label{font-size:.875rem;font-weight:600}.quality-option .hint{grid-column:2}.quality-option.selected{border-color:var(--accent);background:#2563eb0d}.hint{font-size:.75rem;color:var(--text-secondary)}.control-actions{display:flex;align-items:center;justify-content:space-between;margin-top:16px}#file-count{font-size:.875rem;color:var(--text-secondary)}#progress-section{margin-top:20px}.progress-bar-container{height:4px;background:var(--border);border-radius:2px;overflow:hidden}#progress-bar{height:100%;background:var(--accent);width:0%;transition:width .3s ease;border-radius:2px}.progress-info{display:flex;justify-content:space-between;margin-top:8px;font-size:.8125rem;color:var(--text-secondary)}#cancel-btn{margin-top:12px;background:transparent;color:var(--text-secondary);border:1px solid var(--border)}#cancel-btn:hover{background:var(--border)}#results{margin-top:20px}.results-header{display:flex;align-items:center;justify-content:space-between;margin-bottom:12px}#results-summary{font-size:.875rem;color:var(--text-secondary)}.result-row{display:flex;align-items:center;gap:12px;padding:8px 0;border-bottom:1px solid var(--border);font-size:.8125rem}.file-name{flex:1;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}.file-size{color:var(--text-secondary);flex-shrink:0}.download-btn{padding:4px 10px;font-size:.75rem}.error-row .file-name{color:var(--error)}.error-msg{color:var(--error);font-size:.75rem}footer{margin-top:48px;text-align:center}footer p{font-size:.75rem;color:var(--text-secondary)}