* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: Arial, sans-serif;
    background-color: #f0f0f0;
    padding: 0;
    margin: 0;
}

header {
    background-color: #333;
    padding: 15px 20px;
    border-bottom: 3px solid #0066cc;
}

header h1 {
    color: white;
    text-align: center;
    margin-bottom: 15px;
    font-size: 2em;
}

.menu {
    display: flex;
    justify-content: center;
    gap: 20px;
    flex-wrap: wrap;
}

.menu-link {
    color: #fff;
    text-decoration: none;
    font-size: 0.95em;
    font-weight: bold;
    padding: 5px 10px;
    border-bottom: 3px solid transparent;
    cursor: pointer;
    transition: all 0.3s;
}

.menu-link:hover {
    border-bottom: 3px solid #0066cc;
}

.menu-link.active {
    border-bottom: 3px solid #0066cc;
    color: #0066cc;
}

h2 {
    color: #555;
    text-align: center;
    margin-bottom: 30px;
}

h3 {
    color: #333;
    margin-bottom: 15px;
    border-bottom: 2px solid #333;
    padding-bottom: 5px;
}

.contenedor {
    max-width: 600px;
    margin: 20px 0 20px 20px;
    background-color: white;
    padding: 20px;
    border: 2px solid #333;
}

section {
    margin-bottom: 30px;
    padding: 15px;
    border: 1px solid #ccc;
    background-color: #f9f9f9;
    display: none;
    text-align: left;
}

section.active {
    display: block;
}

p {
    margin-bottom: 10px;
    line-height: 1.6;
    color: #333;
    margin-left: 10px;
}

strong {
    color: #0066cc;
}

label {
    display: block;
    margin-bottom: 8px;
    font-weight: bold;
    color: #333;
    margin-left: 10px;
}

input {
    width: calc(100% - 20px);
    padding: 8px;
    margin-bottom: 10px;
    border: 1px solid #999;
    font-size: 1em;
    margin-left: 10px;
}

button {
    padding: 10px 20px;
    background-color: #0066cc;
    color: white;
    border: none;
    font-size: 1em;
    cursor: pointer;
    width: auto;
    margin-left: 10px;
    margin-bottom: 10px;
}

button:hover {
    background-color: #0052a3;
}

button:disabled {
    background-color: #999;
    cursor: not-allowed;
}

.btn-reset {
    background-color: #cc6600;
}

.btn-reset:hover {
    background-color: #994d00;
}

#refuelMessage {
    margin-top: 15px;
    padding: 10px;
    border: 1px solid #ccc;
    display: none;
    white-space: pre-wrap;
    font-family: monospace;
    font-size: 0.9em;
}

#refuelMessage.success {
    background-color: #d4edda;
    color: #155724;
    border: 1px solid #28a745;
    display: block;
}

#refuelMessage.warning {
    background-color: #fff3cd;
    color: #856404;
    border: 1px solid #ffc107;
    display: block;
}

#refuelMessage.error {
    background-color: #f8d7da;
    color: #721c24;
    border: 1px solid #f5c6cb;
    display: block;
}

/* Estilos del Modal */
.modal {
    display: none;
    position: fixed;
    z-index: 1000;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.5);
}

.modal.active {
    display: flex;
    justify-content: center;
    align-items: center;
}

.modal-content {
    background-color: white;
    padding: 30px;
    border: 2px solid #333;
    border-radius: 5px;
    width: 90%;
    max-width: 500px;
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.2);
}

.modal-content h2 {
    margin-bottom: 20px;
    color: #333;
    text-align: center;
    border-bottom: 2px solid #0066cc;
    padding-bottom: 10px;
}

.modal-body {
    margin-bottom: 20px;
}

.modal-body p {
    margin-bottom: 12px;
    font-size: 1.05em;
    line-height: 1.8;
}

.modal-footer {
    text-align: center;
}

.btn-modal {
    padding: 12px 30px;
    background-color: #0066cc;
    color: white;
    border: none;
    font-size: 1em;
    cursor: pointer;
    width: auto;
    min-width: 150px;
    font-weight: bold;
}

.btn-modal:hover {
    background-color: #0052a3;
}

.btn-close {
    background-color: #ff6600;
}

.btn-close:hover {
    background-color: #cc5200;
}