.tool-container{max-width:520px;margin:20px auto;padding:20px;border-radius:12px;background:#fefefe;box-shadow:0 4px 12px rgb(0 0 0 / .1);font-family:'Segoe UI',sans-serif}.tool-container h2{text-align:center;color:#444;margin-bottom:15px}.input-list{list-style:none;padding:0}.input-list li{margin:12px 0;display:flex;justify-content:space-between;align-items:center}.input-list label{flex:1.2}.input-list input{flex:1;padding:8px;border:1px solid #ccc;border-radius:6px}button{width:100%;padding:10px;background:#444;color:#fff;font-size:16px;border:none;border-radius:6px;cursor:pointer}button:hover{background:#222}#fuel-result{margin-top:15px;padding:12px;background:#f7f9fc;border-radius:8px;font-weight:700}