fix: dark mode #50 #53 (#55)

* fix: dark mode #50 #53

* fix: dark mode class name

* chore: simply code

* chore: set empty valueDark

Author: BTBMan

src/dark-mode.ts

@@ -1,10 +1,23 @@
-import { useLocalStorage, useMutationObserver } from '@vueuse/core'
+import { useDark, useLocalStorage, useMutationObserver } from '@vueuse/core'
 
 const setDarkMode = () => {
   setTimeout(() => {
+    const isDark = useDark({ valueDark: '' })
     const vueuseColorScheme = useLocalStorage('vueuse-color-scheme', 'auto')
-    const colorMode = vueuseColorScheme.value === 'auto' ? 'dark' : ''
     const classList = Array.from(document.documentElement.classList)
+    let colorMode
+    if (vueuseColorScheme.value === 'auto') {
+      if (isDark.value)
+        colorMode = 'dark'
+      else
+        colorMode = ''
+    }
+    else if (vueuseColorScheme.value === 'dark') {
+      colorMode = 'dark'
+    }
+    else {
+      colorMode = ''
+    }
 
     if (classList.length && !classList.includes(colorMode)) {
       const classNames = colorMode === 'dark' ? 'htw-dark dark' : ''