/* --- Pengaturan Dasar & Latar Belakang Animasi --- */
body {
    font-family: 'Poppins', sans-serif;
    margin: 0;
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    background: linear-gradient(-45deg, #0a0808, #8e7b83, #23a6d5, #23d5ab);
    background-size: 400% 400%;
    animation: gradientBG 15s ease infinite;
}

@keyframes gradientBG {
    0% { background-position: 0% 50%; }
    50% { background-position: 100% 50%; }
    100% { background-position: 0% 50%; }
}

/* --- Kontainer Login Utama --- */
.login-container {
    padding: 20px;
}

.login-box {
    width: 100%;
    max-width: 400px;
    padding: 40px;
    background-color: rgba(255, 255, 255, 0.1);
    backdrop-filter: blur(10px);
    border-radius: 15px;
    border: 1px solid rgba(255, 255, 255, 0.2);
    box-shadow: 0 8px 32px 0 rgba(0, 0, 0, 0.37);
    text-align: center;
    color: #ffffff;
}

h2 {
    margin-top: 0;
    margin-bottom: 10px;
    font-size: 2rem;
    font-weight: 600;
}

.login-box p {
    margin-bottom: 30px;
    font-size: 0.9rem;
    opacity: 0.8;
}

/* --- Grup Input & Form --- */
.input-group {
    text-align: left;
    margin-bottom: 20px;
}

.input-group label {
    display: block;
    margin-bottom: 5px;
    font-size: 0.9rem;
    font-weight: 600;
}

.input-group input {
    width: 100%;
    padding: 12px 15px;
    border: 1px solid rgba(255, 255, 255, 0.3);
    background-color: rgba(255, 255, 255, 0.15);
    border-radius: 8px;
    color: #ffffff;
    font-family: 'Poppins', sans-serif;
    font-size: 1rem;
    transition: box-shadow 0.3s ease;
}

.input-group input::placeholder {
    color: rgba(255, 255, 255, 0.7);
}

.input-group input:focus {
    outline: none;
    box-shadow: 0 0 0 3px rgba(35, 166, 213, 0.5);
}

/* --- Tombol & Pesan Error --- */
.login-button {
    width: 100%;
    padding: 15px;
    border: none;
    background-color: #23a6d5;
    color: #ffffff;
    font-size: 1.1rem;
    font-weight: 600;
    border-radius: 8px;
    cursor: pointer;
    transition: background-color 0.3s ease;
    margin-top: 10px;
}

.login-button:hover {
    background-color: #2980b9;
}

.error-message {
    background-color: rgba(231, 60, 126, 0.8);
    color: #fff;
    padding: 10px;
    border-radius: 5px;
    margin-bottom: 20px !important;
    font-size: 0.9rem !important;
    opacity: 1 !important;
}

/* --- CSS UNTUK TOMBOL KEMBALI --- */
.back-link {
    display: block;
    margin-top: 20px;
    color: #ffffff;
    text-decoration: none;
    font-size: 0.9rem;
    opacity: 0.8;
    transition: opacity 0.3s ease;
}

.back-link:hover {
    opacity: 1;
    text-decoration: underline;
}

/* --- CSS BARU: MEDIA QUERY UNTUK RESPONSIVE --- */
@media (max-width: 480px) {
    .login-container {
        padding: 10px;
    }

    .login-box {
        padding: 25px;
    }

    h2 {
        font-size: 1.8rem;
    }
}