:root {
            --primary-color: #0d6efd;
            --primary-darker: #0b5ed7;
            --background-color: #f0f2f5;
            --card-background: #ffffff;
            --text-color: #495057;
            --heading-color: #212529;
        }

        /* --- GANTI DENGAN BLOK INI --- */
        body {
            min-height: 100vh; /* Menggunakan vh (viewport height) agar lebih andal */
            background-color: var(--background-color);
            background-image: linear-gradient(to top, #accbee 0%, #e7f0fd 100%);
            font-family: 'Poppins', sans-serif;
            display: flex;
            align-items: center;
            justify-content: center;
            padding: 2rem 1rem; 
        }

        .login-container {
            width: 100%;
            max-width: 480px;
        }
        
        .login-card {
            background-color: var(--card-background);
            border: none;
            border-radius: 16px;
            box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
            overflow: hidden;
            position: relative;
        }

        .login-card-header {
            text-align: center;
            padding: 2.5rem 1.5rem;
            background: linear-gradient(135deg, var(--primary-color), var(--primary-darker));
            color: white;
        }
        
        /* --- PERUBAHAN CSS DI SINI --- */
        .logo-placeholder {
            width: auto;
            max-width: 120px; 
            height: auto;
            margin-bottom: 1.25rem;
            margin-left: auto;   /* Tambahkan baris ini */
            margin-right: auto;  /* Tambahkan baris ini */
        }
        
        .logo-placeholder img {
            /* Menghapus border-radius agar gambar tidak dipaksa bulat */
            max-width: 100%;
            height: auto;
        }
        /* --- AKHIR PERUBAHAN CSS --- */

        .header-title {
            font-size: 2rem;
            font-weight: 700;
            margin-bottom: 0;
            line-height: 1.2;
        }
        
        .header-subtitle {
            font-size: 1.2rem;
            font-weight: 500;
            color: rgba(255, 255, 255, 0.95);
            margin-bottom: 0.5rem;
        }

        .header-system-title {
            font-size: 1rem;
            font-weight: 400;
            opacity: 0.9;
        }

        .admin-login-btn {
            position: absolute;
            top: 1rem;
            right: 1rem;
            background: rgba(255, 255, 255, 0.15);
            border: 1px solid rgba(255, 255, 255, 0.3);
            color: white;
            font-weight: 500;
            border-radius: 20px;
            padding: 0.4rem 0.8rem;
            font-size: 0.8rem;
        }
        .admin-login-btn:hover {
            background-color: rgba(255,255,255,0.3);
            color: white;
        }

        .login-card-body {
            padding: 2rem 2.5rem;
        }

        .form-label {
            font-weight: 600;
            color: var(--heading-color);
            margin-bottom: 0.5rem;
        }
        .form-label i {
            margin-right: 8px;
            width: 16px;
        }
        
        .form-control-lg {
            font-size: 1rem;
            padding: 0.9rem 1.2rem;
            border-radius: 8px;
        }
        .form-control-lg:focus {
             box-shadow: 0 0 0 0.25rem rgba(13, 110, 253, 0.25);
             border-color: var(--primary-color);
        }

        .input-group-text {
            cursor: pointer;
        }

        .btn-primary {
            padding: 0.9rem 1.5rem;
            font-size: 1.1rem;
            font-weight: 600;
        }
        
        .footer-text {
            font-size: 0.85rem;
            text-align: center;
            padding: 1.5rem 1rem;
            color: #6c757d;
        }
        
        .modal-header {
            background-color: #343a40;
            color: white;
        }
        .modal-header .btn-close {
            filter: invert(1) grayscale(100%) brightness(200%);
        }