[web] Updates for CMS pages using BS5 and new site design GitOrigin-RevId: 08b66d1bfb3062a229f16a44efe70527f6fa67a7
[web] Begin to migrate `website-redesign.less` to BS5 GitOrigin-RevId: e3cf2162e819f7c137bbc2715dcd9a9fe6d72f3f