* {
            margin: 0;
            padding: 0;
            box-sizing: border-box;
            font-family: Arial, sans-serif;
        }

        body {
            background: linear-gradient(135deg, #2b2f6a, #5a5ea8);
            min-height: 100vh;
            display: flex;
            align-items: center;
            justify-content: center;
        }

        .login-container {
            width: 900px;
            background: #fff;
            display: flex;
            border-radius: 8px;
            overflow: hidden;
            box-shadow: 0 10px 30px rgba(0,0,0,0.25);
        }

        .login-left {
            width: 40%;
            background: #2b2f6a;
            color: #fff;
            padding: 40px 25px;
            text-align: center;
        }

        .login-left i {
            font-size: 70px;
            margin: 20px 0;
        }

        .login-left h2 {
            font-size: 22px;
        }

        .login-left p {
            font-size: 14px;
            margin-top: 20px;
            line-height: 1.6;
        }

        .login-right {
            width: 60%;
            padding: 40px;
        }

        .login-right h3 {
            margin-bottom: 20px;
            color: #2b2f6a;
        }

        .form-group {
            margin-bottom: 18px;
        }

        .form-group label {
            display: block;
            margin-bottom: 6px;
            font-size: 14px;
            font-weight: bold;
        }

        .form-group input {
            width: 100%;
            padding: 10px;
            border: 1px solid #ccc;
            border-radius: 4px;
            font-size: 14px;
        }

        .captcha-box {
            display: flex;
            align-items: center;
            gap: 10px;
        }

        .captcha-text {
            background: #f1f1f1;
            padding: 10px 15px;
            font-weight: bold;
            letter-spacing: 3px;
            font-size: 18px;
            border-radius: 4px;
            color: #2b2f6a;
            user-select: none;
        }

        .refresh-btn {
            background: #2b2f6a;
            color: #fff;
            border: none;
            padding: 8px 10px;
            border-radius: 4px;
            cursor: pointer;
        }

        .login-btn {
            width: 100%;
            padding: 12px;
            background: #2b2f6a;
            color: #fff;
            border: none;
            border-radius: 4px;
            font-size: 15px;
            font-weight: bold;
            cursor: pointer;
        }

        .login-btn:hover {
            background: #3f44a3;
        }

        .login-footer {
            margin-top: 15px;
            font-size: 13px;
            color: #666;
            text-align: center;
        }

        .error {
            color: red;
            font-size: 13px;
            margin-bottom: 10px;
        }

        @media(max-width: 768px) {
            .login-container {
                flex-direction: column;
                width: 95%;
            }
            .login-left, .login-right {
                width: 100%;
            }
        }