:root{--bg-color: #0f172a;--card-bg: #1e293b;--text-primary: #f8fafc;--text-secondary: #94a3b8;--accent-primary: #3b82f6;--accent-hover: #2563eb;--success: #22c55e;--error: #ef4444;--border: #334155}*{box-sizing:border-box}body{margin:0;padding:0;font-family:Inter,-apple-system,BlinkMacSystemFont,sans-serif;background-color:var(--bg-color);color:var(--text-primary);-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale}#root{min-height:100vh}.app-container{max-width:900px;margin:0 auto;padding:1.5rem;min-height:100vh;display:flex;flex-direction:column}.loading-screen{min-height:100vh;display:flex;flex-direction:column;align-items:center;justify-content:center;gap:1rem}.spinner{width:40px;height:40px;border:3px solid var(--border);border-top-color:var(--accent-primary);border-radius:50%;animation:spin 1s linear infinite}@keyframes spin{to{transform:rotate(360deg)}}header{text-align:center;margin-bottom:1.5rem}h1{margin:0;font-size:1.75rem;font-weight:800;background:linear-gradient(to right,#60a5fa,#3b82f6);-webkit-background-clip:text;-webkit-text-fill-color:transparent}.subtitle{color:var(--text-secondary);margin:.5rem 0 0;font-size:.9rem}main{flex:1}.steps-indicator{display:flex;align-items:center;justify-content:center;margin-bottom:2rem;gap:.5rem;flex-wrap:wrap}.step{display:flex;flex-direction:column;align-items:center;gap:.25rem}.step-num{width:32px;height:32px;border-radius:50%;background:var(--card-bg);border:2px solid var(--border);display:flex;align-items:center;justify-content:center;font-weight:600;font-size:.875rem;color:var(--text-secondary)}.step.active .step-num{background:var(--accent-primary);border-color:var(--accent-primary);color:#fff}.step.completed .step-num{background:var(--success);border-color:var(--success);color:#fff}.step-label{font-size:.7rem;color:var(--text-secondary)}.step.active .step-label{color:var(--accent-primary)}.step.completed .step-label{color:var(--success)}.step-line{width:24px;height:2px;background:var(--border);margin-bottom:1rem}.card{background:var(--card-bg);border:1px solid var(--border);border-radius:1rem;padding:1.25rem}.content-area{display:flex;flex-direction:column;gap:1.5rem}.error-message{color:var(--error);padding:.75rem 1rem;background:#ef44441a;border-radius:.5rem;font-size:.875rem;text-align:center}.upload-section{display:flex;flex-direction:column;align-items:center;gap:1rem;padding:3rem 1.5rem;text-align:center}.upload-icon{color:var(--text-secondary)}.upload-section h2{margin:0;font-size:1.25rem}.hint{color:var(--text-secondary);margin:0;font-size:.875rem}.button{padding:.75rem 1.5rem;border-radius:.5rem;font-weight:600;cursor:pointer;border:none;transition:all .2s;text-decoration:none;display:inline-flex;align-items:center;justify-content:center;gap:.5rem;font-size:.9rem}.button:disabled{opacity:.5;cursor:not-allowed}.primary{background:var(--accent-primary);color:#fff}.primary:hover:not(:disabled){background:var(--accent-hover)}.secondary{background:transparent;border:1px solid var(--border);color:var(--text-primary)}.secondary:hover:not(:disabled){background:var(--border)}.success{background:var(--success);color:#fff}.success:hover:not(:disabled){background:#16a34a}.small{padding:.5rem 1rem;font-size:.8rem}.full-width{width:100%}.extract-section{display:flex;flex-direction:column;gap:1.5rem;align-items:center}.preview-card{display:flex;flex-direction:column;align-items:center;gap:.75rem;width:100%;max-width:500px;margin:0 auto}.video-preview{width:100%;max-height:50vh;border-radius:.5rem;background:#000}.label{font-size:.8rem;color:var(--text-secondary);font-weight:500}.upscale-section{display:flex;flex-direction:column;gap:1.5rem}.frames-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(200px,1fr));gap:1rem}.frames-grid .preview-card img{width:100%;max-height:200px;object-fit:contain;border-radius:.5rem;background:#000}.upscale-instructions{text-align:center}.upscale-instructions h3{margin:0 0 .5rem;font-size:1rem}.upscale-instructions p{color:var(--text-secondary);margin:0 0 1rem;font-size:.875rem}.generate-section{display:flex;flex-direction:column;gap:1.5rem}.config-card{display:flex;flex-direction:column;gap:1rem}.config-card h3{margin:0;font-size:1rem}.control-group{display:flex;flex-direction:column;gap:.5rem}.control-group label{font-size:.875rem;color:var(--text-secondary)}input[type=range]{width:100%;height:6px;-webkit-appearance:none;background:var(--bg-color);border-radius:3px;outline:none}input[type=range]::-webkit-slider-thumb{-webkit-appearance:none;width:18px;height:18px;background:var(--accent-primary);border-radius:50%;cursor:pointer}.result-section{display:flex;flex-direction:column;gap:1.5rem}.result-section .preview-card{max-width:600px;margin:0 auto}.actions{display:flex;gap:1rem;justify-content:center;flex-wrap:wrap}.progress-bar{height:4px;background:var(--border);border-radius:2px;overflow:hidden}.progress-fill{height:100%;background:var(--accent-primary);transition:width .3s ease}footer{text-align:center;padding:1.5rem 0 0;margin-top:auto}footer p{margin:0;font-size:.75rem;color:var(--text-secondary)}@media(max-width:600px){.app-container{padding:1rem}h1{font-size:1.5rem}.steps-indicator{gap:.25rem}.step-line{width:16px}.step-num{width:28px;height:28px;font-size:.8rem}.step-label{font-size:.65rem}.upload-section{padding:2rem 1rem}.frames-grid{grid-template-columns:1fr}.actions{flex-direction:column}.button{width:100%}}