/* Reset cơ bản */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background: linear-gradient(to right, #74ebd5, #ACB6E5);
    min-height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 20px;
}

/* Card chính */
.login-card {
    background-color: #ffffff;
    border-radius: 12px;
    box-shadow: 0 6px 20px rgba(0, 0, 0, 0.1);
    width: 100%;
    max-width: 400px;
    padding: 30px 25px;
    transition: all 0.3s ease-in-out;
}

/* Header */
.login-card__header {
    text-align: center;
    margin-bottom: 20px;
}

.login-card__heading {
    font-size: 24px;
    color: #333333;
    font-weight: 600;
}

/* Form control */
.form-group {
    margin-bottom: 18px;
    display: flex;
    flex-direction: column;
}

.form-group label {
    margin-bottom: 6px;
    color: #444;
    font-weight: 500;
}

.form-control {
    padding: 10px 12px;
    border: 1px solid #ccc;
    border-radius: 6px;
    font-size: 16px;
    outline: none;
    transition: border 0.2s;
}

.form-control:focus {
    border-color: #007bff;
    box-shadow: 0 0 3px rgba(0, 123, 255, 0.3);
}

/* Button */
.btn {
    padding: 10px 15px;
    font-size: 16px;
    border-radius: 6px;
    border: none;
    cursor: pointer;
    width: 100%;
    transition: background-color 0.3s;
}

.btn-primary {
    background-color: #007bff;
    color: white;
}

.btn-primary:hover {
    background-color: #0056b3;
}

/* Responsive nhỏ hơn */
@media (max-width: 480px) {
    .login-card {
        padding: 20px 15px;
    }

    .login-card__heading {
        font-size: 20px;
    }

    .form-control {
        font-size: 15px;
    }

    .btn {
        font-size: 15px;
    }
}
.loading-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(255, 255, 255, 0.7);
    z-index: 9999;
    display: flex;
    align-items: center;
    justify-content: center;
}

.spinner {
    width: 60px;
    height: 60px;
    border: 6px solid #f3f3f3;
    border-top: 6px solid #007bff;
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

@keyframes spin {
    to {
        transform: rotate(360deg);
    }
}

.hidden {
    display: none !important;
}