:root{font-family:Inter,ui-sans-serif,system-ui,-apple-system,BlinkMacSystemFont,Segoe UI,sans-serif;color:#f9fafb;background:#0b1020}*{box-sizing:border-box}body{min-width:320px;min-height:100vh;margin:0;background:radial-gradient(circle at 20% 0%,#263b70 0,transparent 35rem),#0b1020}button{border:0;border-radius:10px;padding:.75rem 1.05rem;color:#07101e;background:#7dd3fc;font:inherit;font-weight:700;cursor:pointer}button:hover{background:#bae6fd}button.secondary{color:#dbeafe;background:#26324a}.app-shell{width:min(1120px,calc(100% - 2rem));margin:0 auto;padding:10vh 0 3rem}header{max-width:670px;margin-bottom:2rem}.eyebrow{margin:0 0 .75rem;color:#7dd3fc;font-size:.82rem;font-weight:800;letter-spacing:.12em;text-transform:uppercase}h1{margin:0;font-size:clamp(2rem,5vw,4.5rem);letter-spacing:-.06em;line-height:1}.subtitle{color:#b8c3da;line-height:1.55}.drop-zone{min-height:390px;border:2px dashed #435475;border-radius:20px;background:#111827b8;transition:.18s ease}.drop-zone.dragging{border-color:#7dd3fc;background:#0e749038;transform:scale(1.01)}.drop-zone.busy{pointer-events:none;opacity:.72}.empty-state{min-height:390px;display:grid;place-content:center;justify-items:center;gap:1rem;text-align:center;color:#d9e2f1}.empty-state p{font-size:1.2rem;margin:0}.empty-state small{color:#8392ad}.upload-icon{width:54px;height:54px;display:grid;place-items:center;border-radius:50%;color:#b8ecff;background:#173253;font-size:2rem}.result-state{padding:1.1rem}.comparison{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:1rem}figure{min-width:0;margin:0}figcaption{margin:0 0 .55rem;color:#b8c3da;font-size:.9rem}figure>img,.checkerboard{display:block;width:100%;min-height:260px;max-height:560px;object-fit:contain;border-radius:12px;background:#050812}.checkerboard{background-color:#d5dce9;background-image:linear-gradient(45deg,#b5bece 25%,transparent 25%),linear-gradient(-45deg,#b5bece 25%,transparent 25%),linear-gradient(45deg,transparent 75%,#b5bece 75%),linear-gradient(-45deg,transparent 75%,#b5bece 75%);background-size:24px 24px;background-position:0 0,0 12px,12px -12px,-12px 0}.checkerboard img{width:100%;height:100%;max-height:560px;object-fit:contain}.actions{display:flex;justify-content:center;gap:.75rem;margin:1.25rem 0 .25rem}.status{min-height:1.5rem;margin:1rem 0;color:#b8c3da;text-align:center}.status.error{color:#fda4af}@media(max-width:680px){.app-shell{padding-top:3rem}.comparison{grid-template-columns:1fr}figure>img,.checkerboard{min-height:200px}.actions{flex-direction:column}}