:root{--bg:#3a6ea5;--dialog:#ece9d8;--text:#000;--title:#0a246a;--title-text:#fff;--border:gray;--error:#c00;font-family:Tahoma,Verdana,Segoe UI,sans-serif}*{box-sizing:border-box}body{background:var(--bg);min-height:100vh;color:var(--text);margin:0}main{max-width:560px;margin:0 auto;padding:32px 16px}h1,.tagline{color:#fff;text-align:center}.dialog{background:var(--dialog);border:2px solid var(--border);border-radius:6px 6px 0 0;margin-top:24px;padding:0 16px 16px}.dialog h2{background:var(--title);color:var(--title-text);border-radius:4px 4px 0 0;margin:0 -16px 16px;padding:6px 12px;font-size:1rem}.error h2{background:var(--error)}.drop{border:2px dashed var(--border);text-align:center;cursor:pointer;padding:32px 16px;display:block}.drop.dragging{background:#fff}.drop input{opacity:0;width:1px;height:1px;position:absolute}.drop:focus-within{outline:2px solid var(--title);outline-offset:2px}.note{font-size:.85rem}progress{width:100%;height:20px}.buttons{flex-wrap:wrap;gap:8px;display:flex}button{font:inherit;min-height:32px;padding:6px 16px}