:root{--bg:#0f1117;--surface:#1a1d27;--surface-2:#22263a;--border:#2e3148;--text:#c9cdd8;--text-dim:#6b7280;--accent:#6366f1;--accent-hover:#4f46e5;--radius:12px;color:var(--text);background:var(--bg);font-family:system-ui,Segoe UI,Roboto,sans-serif;font-size:16px}*,:before,:after{box-sizing:border-box;margin:0;padding:0}[hidden]{display:none!important}body{min-height:100svh}.topbar{z-index:10;-webkit-backdrop-filter:blur(12px);backdrop-filter:blur(12px);border-bottom:1px solid var(--border);background:#0f1117d9;justify-content:space-between;align-items:center;height:52px;padding:0 24px;display:flex;position:sticky;top:0}.topbar-brand{color:#fff;letter-spacing:-.02em;align-items:center;gap:8px;font-size:.95rem;font-weight:700;display:flex}.topbar-brand svg{color:var(--accent)}.topbar-tag{color:var(--accent);letter-spacing:.02em;text-transform:uppercase;background:#6366f11f;border:1px solid #6366f14d;border-radius:999px;padding:3px 10px;font-size:.72rem;font-weight:600}#app{flex-direction:column;gap:40px;width:100%;max-width:780px;margin:0 auto;padding:56px 24px 96px;display:flex}header{text-align:center;border-bottom:1px solid var(--border);flex-direction:column;align-items:center;gap:14px;padding-bottom:8px;display:flex}.header-icon{background:var(--surface);border:1px solid var(--border);width:64px;height:64px;color:var(--accent);border-radius:16px;justify-content:center;align-items:center;display:flex}h1{color:#fff;letter-spacing:-.03em;margin:0;font-size:2.4rem;font-weight:700}.subtitle{color:var(--text-dim);max-width:480px;font-size:.95rem;line-height:1.6}.feature-pills{flex-wrap:wrap;justify-content:center;gap:8px;display:flex}.pill{background:var(--surface);border:1px solid var(--border);color:var(--text-dim);border-radius:999px;align-items:center;gap:5px;padding:5px 12px;font-size:.8rem;display:inline-flex}.pill svg{color:var(--accent);flex-shrink:0}h2{color:#fff;font-size:1.1rem;font-weight:600}#upload-zone{border:2px dashed var(--border);border-radius:var(--radius);text-align:center;cursor:pointer;-webkit-user-select:none;user-select:none;flex-direction:column;align-items:center;gap:12px;padding:60px 24px;transition:border-color .2s,background .2s;display:flex}#upload-zone:hover,#upload-zone.drag-over{border-color:var(--accent);background:#6366f10f}#upload-zone:focus-visible{outline:2px solid var(--accent);outline-offset:2px}.upload-icon{color:var(--text-dim)}.upload-label{color:var(--text);font-size:1.05rem;font-weight:500}.upload-hint{color:var(--text-dim);font-size:.85rem}#preview-section{flex-direction:column;gap:20px;display:flex}#video-preview{border-radius:var(--radius);background:#000;width:100%;max-height:380px;display:block}.controls-panel{background:var(--surface);border:1px solid var(--border);border-radius:var(--radius);flex-direction:column;gap:20px;padding:24px;display:flex}.info-row{color:var(--text-dim);align-items:center;gap:8px;font-size:.9rem;display:flex}.info-row svg{flex-shrink:0}.chunk-row{flex-wrap:wrap;align-items:center;gap:12px;display:flex}.chunk-row label{color:var(--text);font-weight:500}.chunk-row input[type=number]{background:var(--surface-2);border:1px solid var(--border);color:#fff;text-align:center;-moz-appearance:textfield;border-radius:8px;width:80px;padding:8px 12px;font-size:1rem}.chunk-row input[type=number]::-webkit-inner-spin-button{opacity:1}.chunk-row input[type=number]::-webkit-outer-spin-button{opacity:1}.chunk-row input[type=number]:focus{border-color:var(--accent);outline:none}.unit{color:var(--text-dim)}.segment-count{color:var(--accent);font-size:.9rem;font-weight:600}#split-btn{background:var(--accent);color:#fff;cursor:pointer;letter-spacing:.01em;border:none;border-radius:8px;align-self:flex-start;padding:11px 28px;font-size:.95rem;font-weight:600;transition:background .15s,opacity .15s}#split-btn:hover:not(:disabled){background:var(--accent-hover)}#split-btn:disabled{opacity:.35;cursor:not-allowed}#progress-section{background:var(--surface);border:1px solid var(--border);border-radius:var(--radius);flex-direction:column;gap:12px;padding:24px;display:flex}progress{background:var(--surface-2);border:none;border-radius:4px;width:100%;height:8px;display:block}progress::-webkit-progress-bar{background:var(--surface-2);border-radius:4px}progress::-webkit-progress-value{background:var(--accent);border-radius:4px;transition:width .25s}progress::-moz-progress-bar{background:var(--accent);border-radius:4px}.progress-text{color:var(--text-dim);font-size:.875rem}#results-section{flex-direction:column;gap:16px;display:flex}.download-grid{grid-template-columns:repeat(auto-fill,minmax(180px,1fr));gap:12px;display:grid}.segment-card{background:var(--surface);border:1px solid var(--border);border-radius:var(--radius);flex-direction:column;gap:6px;padding:16px;text-decoration:none;transition:border-color .15s,background .15s;display:flex}.segment-card:hover{border-color:var(--accent);background:var(--surface-2)}.segment-num{color:var(--accent);text-transform:uppercase;letter-spacing:.06em;font-size:.7rem;font-weight:700}.segment-range{color:#fff;font-size:.95rem;font-weight:500}.segment-size{color:var(--text-dim);font-size:.8rem}.segment-dl{color:var(--accent);margin-top:4px;font-size:.8rem}