:root {
    --primary-color: #007bff;
    --secondary-color: #6c757d;
    --success-color: #28a745;
    --danger-color: #dc3545;
    --light-color: #f8f9fa;
    --dark-color: #343a40;
    --background-color: #f4f7f6;
    --radius: 8px;
}

/* Reset & Base */
* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background-color: var(--background-color);
    color: var(--dark-color);
    line-height: 1.6;
}

.container {
    width: 90%;
    max-width: 960px;
    margin: 2rem auto;
    padding: 1rem;
}

/* --- Buttons --- */
.btn {
    display: inline-block;
    background: var(--primary-color);
    color: #fff;
    padding: 0.75rem 1.5rem;
    border: none;
    border-radius: var(--radius);
    cursor: pointer;
    text-decoration: none;
    font-size: 1rem;
    transition: all 0.3s ease;
}

.btn:hover {
    background: #0056b3;
    transform: translateY(-2px);
}

.btn-block {
    display: block;
    width: 100%;
}

.btn-secondary {
    background: var(--secondary-color);
}
.btn-secondary:hover {
    background: #5a6268;
}

.btn-danger {
    background: var(--danger-color);
}
.btn-danger:hover {
    background: #b02a37;
}

.btn-success {
    background: var(--success-color);
}
.btn-success:hover {
    background: #218838;
}

/* Tombol kembali */
.btn-back {
    background: #6c757d;
    color: #fff;
    padding: 0.75rem 1.5rem;
    border: none;
    border-radius: var(--radius);
    cursor: pointer;
    text-decoration: none;
    transition: background 0.3s ease;
}
.btn-back:hover {
    background: #5a6268;
}

/* --- Alerts --- */
.alert {
    padding: 1rem;
    margin-bottom: 1rem;
    border-radius: var(--radius);
    border: 1px solid transparent;
}

.alert-danger {
    color: #721c24;
    background-color: #f8d7da;
    border-color: #f5c6cb;
}

.alert-success {
    color: #155724;
    background-color: #d4edda;
    border-color: #c3e6cb;
}

/* --- Login Page --- */
.login-container {
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    background: linear-gradient(135deg, var(--primary-color), #0056b3);
}

.login-form {
    background: #fff;
    padding: 2.5rem;
    border-radius: var(--radius);
    box-shadow: 0 10px 20px rgba(0,0,0,0.1);
    width: 100%;
    max-width: 400px;
    text-align: center;
}

.login-form h2 {
    margin-bottom: 1.5rem;
    color: var(--dark-color);
}

.form-group {
    margin-bottom: 1rem;
    text-align: left;
}

.form-group label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: bold;
}

.form-control {
    width: 100%;
    padding: 0.75rem;
    border: 1px solid #ccc;
    border-radius: var(--radius);
    font-size: 1rem;
}

/* --- Voucher Page --- */
.voucher-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 1.5rem;
}

.voucher-card {
    background: #fff;
    border: 1px solid #ddd;
    border-radius: var(--radius);
    padding: 1.5rem;
    text-align: center;
    box-shadow: 0 4px 8px rgba(0,0,0,0.05);
    transition: transform 0.2s, box-shadow 0.2s;
}
.voucher-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 8px 16px rgba(0,0,0,0.1);
}
.voucher-card h3 {
    margin-bottom: 0.5rem;
}
.voucher-card .price {
    font-size: 1.8rem;
    font-weight: bold;
    color: var(--primary-color);
    margin-bottom: 0.5rem;
}
.voucher-card .duration {
    color: var(--secondary-color);
    margin-bottom: 1rem;
}

/* --- Modal --- */
.modal-overlay {
    display: none;
    position: fixed;
    top: 0; left: 0;
    width: 100%; height: 100%;
    background: rgba(0,0,0,0.6);
    z-index: 1000;
    justify-content: center;
    align-items: center;
    opacity: 0;
    transition: opacity 0.3s ease;
}
.modal-overlay.show {
    display: flex;
    opacity: 1;
}

.modal-content {
    background: #fff;
    padding: 2rem;
    border-radius: var(--radius);
    box-shadow: 0 10px 30px rgba(0,0,0,0.3);
    width: 90%;
    max-width: 500px;
    position: relative;
    transform: scale(0.9);
    transition: transform 0.3s ease;
}
.modal-overlay.show .modal-content {
    transform: scale(1);
}

.modal-close {
    position: absolute;
    top: 1rem; right: 1rem;
    background: none;
    border: none;
    font-size: 1.5rem;
    cursor: pointer;
    color: var(--secondary-color);
}

.modal-header {
    margin-bottom: 1.5rem;
    border-bottom: 1px solid #eee;
    padding-bottom: 1rem;
}
.modal-header h3 {
    margin: 0;
    color: var(--dark-color);
}

.modal-body .form-group {
    margin-bottom: 1rem;
}
.modal-body label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: bold;
}
.modal-body .form-control {
    width: 100%;
    padding: 0.75rem;
    border: 1px solid #ccc;
    border-radius: var(--radius);
    font-size: 1rem;
}

/* --- Selected Package --- */
.selected-package {
    background-color: var(--light-color);
    padding: 1rem;
    border-radius: var(--radius);
    margin-bottom: 1.5rem;
    text-align: center;
}
.selected-package .price {
    font-size: 1.5rem;
    font-weight: bold;
    color: var(--primary-color);
}

/* --- Status Page --- */
.status-container {
    background: white;
    padding: 2rem;
    border-radius: var(--radius);
    box-shadow: 0 5px 15px rgba(0,0,0,0.1);
    text-align: center;
}
.status-container h1 {
    color: var(--success-color);
    margin-bottom: 1rem;
}

/* --- Error/Failed Transaction Page --- */
.error-container {
    background: white;
    padding: 2rem;
    border-radius: var(--radius);
    box-shadow: 0 5px 15px rgba(0,0,0,0.1);
    text-align: center;
}
.error-container h1 {
    color: var(--danger-color);
    margin-bottom: 1rem;
}
.error-container p {
    margin-bottom: 1.5rem;
}

/* --- Responsive --- */
@media (max-width: 768px) {
    .container {
        width: 95%;
        margin: 1rem auto;
    }
    .login-form {
        padding: 1.5rem;
    }
}