:root{font-family:system-ui,-apple-system,sans-serif;color:#1a1a2e;background:#f4f5f7}body{margin:0;display:flex;min-height:100vh;align-items:center;justify-content:center}.card{background:#fff;border-radius:8px;box-shadow:0 2px 12px #00000014;padding:2rem;width:320px}.card h1{font-size:1.25rem;margin:0 0 1rem}.card form{display:flex;flex-direction:column;gap:.75rem}.card input{padding:.5rem .75rem;border:1px solid #cbd2d9;border-radius:4px;font-size:1rem}.card button{padding:.6rem;border:none;border-radius:4px;background:#1a6feb;color:#fff;font-size:1rem;cursor:pointer}.card button:disabled{background:#9db8dd;cursor:default}.code-boxes{position:relative;display:flex;gap:.5rem;cursor:text}.code-box{flex:1;aspect-ratio:1;display:flex;align-items:center;justify-content:center;border:1px solid #cbd2d9;border-radius:4px;font-size:1.5rem;background:#fff}.code-box.active{border-color:#1a6feb}.code-hidden-input{position:absolute;top:0;right:0;bottom:0;left:0;width:100%;height:100%;opacity:0;border:none;padding:0}.error{color:#c0392b;font-size:.875rem;margin:0}.hint{color:#5a6472;font-size:.875rem;margin:0}