/*   Tổng thể nền ảnh anime */
body {
    font-family: 'Poppins', sans-serif;
    background-image: url('https://4kwallpapers.com/images/walls/thumbs_3t/2537.jpg'); /*   Thay link ảnh nền tại đây */
    background-size: cover;
    background-position: center;
    background-repeat: no-repeat;
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    position: relative;
    overflow: hidden;
}

/*   Overlay nhẹ làm dịu ảnh */
body::after {
    content: "";
    position: absolute;
    inset: 0;
    background: rgba(255, 240, 250, 0.4);
    backdrop-filter: blur(3px);
    z-index: 0;
}

/*   Thẻ đăng nhập */
.login-card {
    width: 100%;
    max-width: 400px;
    border-radius: 20px;
    overflow: hidden;
    box-shadow: 0 10px 40px rgba(255,120,180,0.3);
    background: rgba(255,255,255,0.35);
    backdrop-filter: blur(18px);
    animation: fadeIn 1s ease forwards;
    z-index: 1;
}
@keyframes fadeIn {
    from { opacity: 0; transform: translateY(30px); }
    to { opacity: 1; transform: translateY(0); }
}

/*   Header */
.login-header {
    background: rgba(255,255,255,0.25);
    text-align: center;
    padding: 20px 15px;
    border-bottom: 1px solid rgba(255,255,255,0.3);
}
.login-header h2 {
    font-family: 'Pacifico', cursive;
    font-size: 1.9rem;
    color: #ff4f9a;
    margin-bottom: 5px;
    text-shadow: 0 1px 5px rgba(255,150,200,0.4);
}
.login-header p {
    color: #444;
    font-size: 0.95rem;
}

/*   Thân form trong suốt mờ (glassmorphism) */
.login-body {
    padding: 30px;
    background: rgba(255,255,255,0.25);
    backdrop-filter: blur(20px);
    border-top: 1px solid rgba(255,255,255,0.25);
    border-bottom-left-radius: 20px;
    border-bottom-right-radius: 20px;
}

/*   Input */
.form-label {
    font-weight: 600;
    font-size: 0.95rem;
    margin-bottom: 6px;
    color: #333;
}
.form-control {
    border-radius: 12px;
    padding: 10px 12px;
    border: 1px solid rgba(255,255,255,0.5);
    background: rgba(255,255,255,0.4);
    color: #333;
    transition: all 0.3s ease;
}
.form-control::placeholder {
    color: rgba(80,80,80,0.7);
}
.form-control:focus {
    border-color: #ff7fb5;
    box-shadow: 0 0 0 0.2rem rgba(255,130,180,0.25);
    background: rgba(255,255,255,0.6);
}

/*   Nút đăng nhập */
.btn-login {
    border-radius: 25px;
    padding: 10px 0;
    background: linear-gradient(135deg, #ff94c2 0%, #ffaee3 100%);
    border: none;
    color: white;
    font-weight: 600;
    font-size: 1rem;
    transition: all 0.3s ease;
    box-shadow: 0 5px 15px rgba(255,120,180,0.25);
}
.btn-login:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 22px rgba(255,120,180,0.4);
}

/*   Thông báo */
.alert {
    border-radius: 10px;
    font-size: 0.9rem;
    padding: 10px 15px;
    background: rgba(255,255,255,0.6);
    backdrop-filter: blur(8px);
}

/*   Link */
.text-center a {
    color: #ff4f9a;
    text-decoration: none;
    font-weight: 500;
}
.text-center a:hover {
    text-decoration: underline;
}

/*   Responsive */
@media (max-width: 576px) {
    .login-card { margin: 0 15px; }
    .login-body { padding: 25px 20px; }
}