• Remove supports for Internet Explorer (IE).
• Supports only latest 10 versions of major browser from current.
• Use CSS @supports() to prevent some browsers that did not support some CSS features such as hsa( from (--variable) ...).

Rebuild from updated dependency packages.

• Fix CSS round() function missing third argument 1px.

Same features based on original Bootstrap 3.4.1 but use new CSS variables and CSS relative color syntax.