body {
    font-family: Arial, sans-serif;
    margin: 0;
    padding: 0;
}
html .container {
    height: 100vh;
    padding: 25px;
    text-align: center;
}
html .container input[type='checkbox'] {
    opacity: 0;
    position: absolute;
}
html .container button,
html .container #checkboxLabel {
    border: none;
    border-radius: 5px;
    cursor: pointer;
    display: inline-block;
    padding: 10px 20px;
}
html[data-theme='dark'] .container {
    background-color: #333;
    color: #fff;
}
html[data-theme='dark'] .container button,
html[data-theme='dark'] .container #checkboxLabel {
    background-color: #F6F6F6;
    color: #333;
}
html:not([data-theme='dark']) .container {
    background-color: #fff;
    color: #333;
}
html:not([data-theme='dark']) .container button,
html:not([data-theme='dark']) .container #checkboxLabel {
    background-color: #A1A1A1;
    color: #ffffff;
}