*,*:before,*:after{box-sizing:border-box}:root{--bg: #0f0f1a;--surface: #1a1a2e;--border: #2d2d44;--text: #f0f0f5;--muted: #9898b0;--accent: #6366f1;--accent-hover: #818cf8;--success: #4ade80;--error: #f87171;--radius: 12px}html,body{margin:0;padding:0;min-height:100%;background:var(--bg);color:var(--text);font-family:system-ui,-apple-system,Segoe UI,Roboto,sans-serif;-webkit-font-smoothing:antialiased}#root{min-height:100vh}.app{max-width:720px;margin:0 auto;padding:1rem 1rem 2rem;min-height:100vh;display:flex;flex-direction:column}.header{text-align:center;padding:.5rem 0 1rem}.header h1{margin:0;font-size:1.5rem;font-weight:700;letter-spacing:-.02em}.header p{margin:.25rem 0 0;color:var(--muted);font-size:.9rem}.banner{padding:.75rem 1rem;border-radius:var(--radius);margin-bottom:1rem;font-size:.875rem;text-align:center}.banner-info{background:#6366f126;border:1px solid rgba(99,102,241,.3);color:#a5b4fc}.banner-error{background:#f871711f;border:1px solid rgba(248,113,113,.3);color:var(--error)}.capture-section,.adjust-section,.result-section{flex:1;display:flex;flex-direction:column;gap:1rem}.preview-wrap{position:relative;width:100%;aspect-ratio:3 / 4;max-height:70vh;background:var(--surface);border-radius:var(--radius);overflow:hidden;border:1px solid var(--border)}.preview-video{width:100%;height:100%;object-fit:cover;display:block}.preview-placeholder{position:absolute;top:0;right:0;bottom:0;left:0;display:flex;align-items:center;justify-content:center;color:var(--muted);font-size:.9rem}.quad-overlay{position:absolute;top:0;right:0;bottom:0;left:0;width:100%;height:100%;pointer-events:none}.hint{text-align:center;color:var(--muted);font-size:.875rem;margin:0}.actions{display:flex;flex-wrap:wrap;gap:.75rem;justify-content:center}.btn{padding:.75rem 1.25rem;border-radius:10px;border:none;font-size:.95rem;font-weight:600;cursor:pointer;transition:background .15s,opacity .15s}.btn:disabled{opacity:.45;cursor:not-allowed}.btn-primary{background:var(--accent);color:#fff}.btn-primary:not(:disabled):hover{background:var(--accent-hover)}.btn-secondary{background:var(--surface);color:var(--text);border:1px solid var(--border)}.btn-secondary:not(:disabled):hover{background:#252540}.corner-editor{position:relative;width:100%;border-radius:var(--radius);overflow:hidden;border:1px solid var(--border);background:var(--surface);touch-action:none}.corner-editor img{width:100%;display:block;-webkit-user-select:none;user-select:none;pointer-events:none}.corner-editor svg{position:absolute;top:0;right:0;bottom:0;left:0;width:100%;height:100%}.corner-handle{cursor:grab;touch-action:none}.corner-handle:active{cursor:grabbing}.result-wrap{border-radius:var(--radius);overflow:hidden;border:1px solid var(--border);background:#fff}.result-image{width:100%;display:block}.footer{margin-top:auto;padding-top:2rem;text-align:center;color:var(--muted);font-size:.75rem}@media(min-width:600px){.header h1{font-size:1.75rem}.preview-wrap{aspect-ratio:4 / 3}}