/* --- RESET & BASE --- */
body {
    font-family: "Open Sans", sans-serif;
    line-height: 1.7;
    /* Menggunakan gradasi biru laut dalam ke biru gelap */
    background: linear-gradient(135deg, #001a2d 0%, #004e75 100%);
    background-attachment: fixed;
    color: #ffffff;
    margin: 0;
    -webkit-font-smoothing: antialiased;
}

/* --- CONTAINER GLASS EFFECT --- */
.container {
    /* Background biru laut transparan (Sea Blue Glass) */
    background: rgba(0, 191, 255, 0.07); 
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    /* Border dengan warna biru muda transparan */
    border: 1px solid rgba(0, 255, 255, 0.15);
    border-radius: 15px;
    padding: 20px;
    /* Bayangan lebih lembut berwarna biru gelap */
    box-shadow: 0 8px 32px 0 rgba(0, 0, 0, 0.4);
    margin-top: 20px;
}

/* --- TYPOGRAPHY --- */
h1, h2, .text-main-1 {
    font-family: "Montserrat", sans-serif;
    font-weight: 600;
    /* Warna Biru Cyan/Azure yang cerah */
    color: #00d4ff !important; 
    text-transform: uppercase;
    /* Efek glow biru */
    text-shadow: 0 0 15px rgba(0, 212, 255, 0.5);
}

h1 { font-size: 1.5rem; text-align: center; }
h2.nk-decorated-h-2 { font-size: 1.75rem; display: flex; align-items: center; }

/* Garis dekorasi biru laut */
.nk-decorated-h-2::after {
    content: "";
    flex: 1;
    border-bottom: 4px solid #0077be;
    margin-left: 20px;
    transform: translateY(2px);
}

/* --- NAVIGATION TABS (SEA BLUE GLASS) --- */
.nav-tabs {
    border-bottom: none;
    display: flex;
    flex-wrap: wrap;
    gap: 5px;
}

.nav-tabs .nav-link {
    background: rgba(255, 255, 255, 0.05);
    color: #fff !important;
    border: 1px solid rgba(255, 255, 255, 0.1);
    padding: 10px 15px;
    text-transform: uppercase;
    font-weight: 600;
    font-size: 0.8rem;
    transition: 0.3s;
    border-radius: 5px;
}

.nav-tabs .nav-link.active {
    /* Biru laut yang menyala saat aktif */
    background: rgba(0, 119, 190, 0.6) !important;
    border-color: #00d4ff;
    box-shadow: 0 0 10px rgba(0, 212, 255, 0.3);
}

/* --- BUTTONS (REGISTER & LOGIN) --- */
.link-container {
    display: flex;
    justify-content: center;
    gap: 10px;
    margin: 20px 0;
}

.link-container a {
    width: 50%;
    text-align: center;
    padding: 15px;
    font-weight: bold;
    text-transform: uppercase;
    color: #ffffff;
    text-decoration: none;
    border-radius: 12px;
    transition: 0.3s;
}

/* Tombol DAFTAR - Deep Ocean Glass */
.register-button {
    /* Biru Cerah transparan */
    background: rgba(0, 150, 255, 0.3); 
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    
    border: 1px solid rgba(0, 255, 255, 0.4);
    box-shadow: 0 8px 25px rgba(0, 119, 190, 0.4), 
                inset 0 0 15px rgba(255, 255, 255, 0.1);
    
    color: #ffffff;
    text-shadow: 0 2px 4px rgba(0, 0, 0, 0.3);
    position: relative;
    overflow: hidden;
}

/* Animasi kilauan cahaya putih (seperti riak air) */
.register-button::after {
    content: "";
    position: absolute;
    top: -50%;
    left: -60%;
    width: 30%;
    height: 200%;
    background: rgba(255, 255, 255, 0.4);
    transform: rotate(35deg);
    transition: all 0.6s ease;
}

.register-button:hover::after {
    left: 120%;
}

/* Tombol LOGIN - Ice Crystal Glass */
.login-button {
    background: rgba(255, 255, 255, 0.1);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    
    border: 1px solid rgba(255, 255, 255, 0.2);
    box-shadow: 0 8px 32px 0 rgba(0, 0, 0, 0.2);
    
    color: #00d4ff; /* Teks warna cyan agar kontras */
    transition: all 0.3s ease;
}

.login-button:hover {
    background: rgba(0, 212, 255, 0.15);
    border: 1px solid #00d4ff;
    transform: translateY(-3px);
}

/* Efek umum saat ditekan */
.register-button:active, .login-button:active {
    transform: scale(0.96);
}

/* Logo Shadow - Blue Glow */
center img {
    filter: drop-shadow(0 0 15px rgba(0, 212, 255, 0.6));
}