<h1>Mancuoj</h1>
<button id="bt">
  Click it 🔥
</button>
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@import url("https://fonts.googleapis.com/css2?family=Poppins:wght@300&display=swap");
$dark-color: #111;
$light-color: #eee;
$bg-color: #4c6fff;
body {
  margin: 0;
  padding: 0;
  height: 100vh;
  display: flex;
  justify-content: center;
  align-items: center;
  font-family: Poppins, serif;
}
h1 {
  margin-right: 20px;
}
button {
  width: 100px;
  height: 40px;
  border: 2px solid $bg-color;
  border-radius: 16px;
  outline: none;
}
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.dark {
  background-color: $dark-color;
  color: $light-color;
}
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const changeTheme = () => {
  const bt = document.getElementById("bt");
  const body = document.body;
  bt.addEventListener("click", () => {
    if (body.className === "dark") {
      body.classList.remove("dark");
    } else {
      body.className = "dark";
    }
  });
};
changeTheme();