@mixin theme-variables($theme) {
    @if $theme =='light' {
        // Evangelion Unit-02.
        --primary-color: #d12e36;  // Contrast ratio: 5.05:1
    }
    @else if $theme == 'dark' {
        // Evangelion Unit-01.
        --primary-color: #c09bd9;  // Contrast ratio: 7.01:1
    }
}

:root {
    @include theme-variables('light');
}

[data-theme='dark'] {
    @include theme-variables('dark');
}

@media (prefers-color-scheme: dark) {
    :root:not([data-theme='light']) {
        @include theme-variables('dark');
    }
}