hugo-battheme/static/js/darkmode.js

const checkbox = document.getElementById('darkmode-toggle');
const body = document.querySelector("body");

if (localStorage.getItem('dark')) {
    switchToDark()
} else {
    switchToLight()
}
checkbox.checked = localStorage.getItem('dark')

checkbox.addEventListener("click", function () {
    localStorage.setItem("dark", this.checked)
    if (this.checked) {
        switchToDark()
    } else {
        switchToLight()
    }
})

function switchToLight() {
    // for some reason this needs to be set to null 
    // i am losing my mind
    localStorage.removeItem("dark")
    body.classList.add('light')
}

function switchToDark() {
    body.classList.remove('light')
}