XWavJmP

index.html

<div class="login-box">
  <h2>Login</h2>
  <form id="frm" name="frm" action="/login" method="post">
    <div class="user-box">
      <input type="text" name="username" required>
      <label>Username</label>
    </div>
    <div class="user-box">
      <input type="password" name="password" required>
      <label>Password</label>
    </div>
    <a href="#" onclick="frm.submit();">
      <span></span>
      <span></span>
      <span></span>
      <span></span>
      Submit
    </a>
  </form>
</div>

style.scss

html {
    height: 100%;
}
body {
    margin: 0;
    padding: 0;
    font-family: sans-serif;
    background: linear-gradient(#141e30, #243b55);
}
.login-box {
    position: absolute;
    top: 50%;
    left: 50%;
    width: 400px;
    padding: 40px;
    transform: translate(-50%, -50%);
    background: rgba(0, 0, 0, 0.5);
    box-sizing: border-box;
    box-shadow: 0 15px 25px rgba(0, 0, 0, 0.6);
    border-radius: 10px;
    h2 {
        margin: 0 0 30px;
        padding: 0;
        color: #fff;
        text-align: center;
    }
    .user-box {
        position: relative;
        input {
            width: 100%;
            padding: 10px 0;
            font-size: 16px;
            color: #fff;
            margin-bottom: 30px;
            border: none;
            border-bottom: 1px solid #fff;
            outline: none;
            background: transparent;
            &:focus {
                ~ {
                    label {
                        top: -20px;
                        left: 0;
                        color: #03e9f4;
                        font-size: 12px;
                    }
                }
            }
            &:valid {
                ~ {
                    label {
                        top: -20px;
                        left: 0;
                        color: #03e9f4;
                        font-size: 12px;
                    }
                }
            }
        }
        label {
            position: absolute;
            top: 0;
            left: 0;
            padding: 10px 0;
            font-size: 16px;
            color: #fff;
            pointer-events: none;
            transition: 0.5s;
        }
    }
    form {
        a {
            position: relative;
            display: inline-block;
            padding: 10px 20px;
            color: #03e9f4;
            font-size: 16px;
            text-decoration: none;
            text-transform: uppercase;
            overflow: hidden;
            transition: 0.5s;
            margin-top: 40px;
            letter-spacing: 4px;
        }
    }
    a {
        &:hover {
            background: #03e9f4;
            color: #fff;
            border-radius: 5px;
            box-shadow: 0 0 5px #03e9f4, 0 0 25px #03e9f4, 0 0 50px #03e9f4,
                0 0 100px #03e9f4;
        }
        span {
            position: absolute;
            display: block;
            &:nth-child(1) {
                top: 0;
                left: -100%;
                width: 100%;
                height: 2px;
                background: linear-gradient(90deg, transparent, #03e9f4);
                animation: btn-anim1 1s linear infinite;
            }
            &:nth-child(2) {
                top: -100%;
                right: 0;
                width: 2px;
                height: 100%;
                background: linear-gradient(180deg, transparent, #03e9f4);
                animation: btn-anim2 1s linear infinite;
                animation-delay: 0.25s;
            }
            &:nth-child(3) {
                bottom: 0;
                right: -100%;
                width: 100%;
                height: 2px;
                background: linear-gradient(270deg, transparent, #03e9f4);
                animation: btn-anim3 1s linear infinite;
                animation-delay: 0.5s;
            }
            &:nth-child(4) {
                bottom: -100%;
                left: 0;
                width: 2px;
                height: 100%;
                background: linear-gradient(360deg, transparent, #03e9f4);
                animation: btn-anim4 1s linear infinite;
                animation-delay: 0.75s;
            }
        }
    }
}
@keyframes btn-anim1 {
    0% {
        left: -100%;
    }
    50%,
    100% {
        left: 100%;
    }
}
@keyframes btn-anim2 {
    0% {
        top: -100%;
    }
    50%,
    100% {
        top: 100%;
    }
}
@keyframes btn-anim3 {
    0% {
        right: -100%;
    }
    50%,
    100% {
        right: 100%;
    }
}
@keyframes btn-anim4 {
    0% {
        bottom: -100%;
    }
    50%,
    100% {
        bottom: 100%;
    }
}

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XWavJmP

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