body {
            font-family: Arial, sans-serif;
            display: flex;
            justify-content: center;
            align-items: center;
            height: 100vh;
            margin: 0;
            background-color: #f4f4f4;
        }

        .login-box {
            background-color: #fff;
            padding: 40px;
            border-radius: 8px;
            box-shadow: 0 0 10px rgba(0,0,0,0.1);
            text-align: center;
        }

        .login-box h2 {
            margin: 0 0 20px;
            color: #333;
        }

        .user-box {
            position: relative;
            margin-bottom: 30px;
        }

        .user-box input {
            width: 100%;
            padding: 10px;
            border: none;
            outline: none;
            font-size: 18px;
            color: #333;
            background: transparent;
            z-index: 1;
        }

        .user-box label {
            position: absolute;
            top: 0;
            left: 0;
            padding: 10px;
            pointer-events: none;
            transition: 0.5s;
            color: #888;
        }

        .user-box input:focus ~ label,
        .user-box input:valid ~ label {
            top: -20px;
            left: 0;
            color: #333;
            font-size: 14px;
        }

        .login-box a {
            display: inline-block;
            position: relative;
            padding: 10px 20px;
            font-size: 18px;
            color: #fff;
            text-decoration: none;
            overflow: hidden;
            border-radius: 8px;
            background: linear-gradient(90deg, #333, #555);
            z-index: 0;
        }

        .login-box a span {
            position: absolute;
            display: block;
        }

        .login-box a span:nth-child(1) {
            top: 0;
            left: -100%;
            width: 100%;
            height: 2px;
            background: linear-gradient(90deg, transparent, #333);
        }

        .login-box a span:nth-child(2) {
            bottom: 0;
            right: -100%;
            width: 100%;
            height: 2px;
            background: linear-gradient(270deg, transparent, #333);
        }

        .login-box a span:nth-child(3) {
            bottom: -100%;
            left: 0;
            width: 2px;
            height: 100%;
            background: linear-gradient(180deg, transparent, #333);
        }

        .login-box a span:nth-child(4) {
            top: -100%;
            right: 0;
            width: 2px;
            height: 100%;
            background: linear-gradient(0deg, transparent, #333);
        }

        .login-box a:hover span:nth-child(1) {
            left: 100%;
        }

        .login-box a:hover span:nth-child(2) {
            right: 100%;
        }

        .login-box a:hover span:nth-child(3) {
            bottom: 100%;
        }

        .login-box a:hover span:nth-child(4) {
            top: 100%;
        }