body {
            background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
            min-height: 100vh;
            display: flex;
            align-items: center;
        }

        .login-card {
            background: rgba(255, 255, 255, 0.95);
            border-radius: 20px;
            box-shadow: 0 8px 32px rgba(0, 0, 0, 0.1);
            transition: transform 0.3s ease;
            margin: 20px;
        }

        .login-card:hover {
            transform: translateY(-5px);
        }

        .form-control {
            border: none;
            border-bottom: 2px solid #ddd;
            border-radius: 0;
            padding-left: 40px;
            transition: all 0.3s ease;
        }

        .form-control:focus {
            box-shadow: none;
            border-bottom-color: #667eea;
        }

        .input-group-text {
            position: absolute;
            z-index: 4;
            background: transparent;
            border: none;
            top: 50%;
            left: 12px;
            transform: translateY(-50%);
            color: #666;
            pointer-events: none;
        }

        .error-message {
            color: #dc3545;
            font-size: 0.875em;
            opacity: 0;
            max-height: 0;
            transition: all 0.3s ease;
        }

        .error-message.show {
            opacity: 1;
            max-height: 20px;
        }

        .btn-login {
            background: linear-gradient(135deg, #667eea, #764ba2);
            border: none;
            padding: 12px 30px;
            transition: all 0.3s ease;
        }

        .btn-login:hover {
            transform: translateY(-2px);
            box-shadow: 0 5px 15px rgba(0, 0, 0, 0.2);
        }

        @keyframes shake {
            0% { transform: translateX(0); }
            25% { transform: translateX(10px); }
            50% { transform: translateX(-10px); }
            75% { transform: translateX(10px); }
            100% { transform: translateX(0); }
        }

        .shake {
            animation: shake 0.4s ease-in-out;
        }