<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Document</title>
<link rel="stylesheet" href="style.css">
</head>
<body>
<div class="btn">
<Button>Hover Me!</Button>
<div class="box"></div>
<div class="box2"></div>
</div>
</body>
</html>
@import url("https://fonts.googleapis.com/css2?family=Poppins&display=swap");
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: "Poppins", sans-serif;
}
body {
    display: flex;
    justify-content: center;
    align-items: center;
    height: 100vh;
}
.btn {
    width: 130px;
    height: 40px;
    position: relative;
    display: flex;
    justify-content: center;
    align-items: center;
    position: relative;
}
.btn button {
    position: absolute;
    width: 100%;
    height: 100%;
    border: none;
    background: rgba(255, 255, 255, 0);
    backdrop-filter: blur(20px);
    color: rgba(0, 0, 0, 0.884);
    cursor: pointer;
    font-size: 0.95em;
    transition: all 0.4s;
    border-radius: 20px;
}
.btn button:hover {
    color: white;
}
.box,
.box2 {
    content: "";
    position: absolute;
    top: 10%;
    left: -1.5%;
    width: 100%;
    height: 100%;
    background: none;
    z-index: -2;
    border: 5px solid #0099f7;
    border-radius: 20px;
    transition: all 0.4s;
}
.btn button:hover ~ .box {
    background: #f11712;
    border: 5px solid #f11712;
    top: -10%;
    left: 1.5%;
}

External CSS

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External JavaScript

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