You want to be the best, you MUST put the long yards in! Nothing comes easy in life so stop wishing and start DOING! So many people would rather bitch and moan than help themselves. Dont be one of those negative drainers, start today, make a small change and keep going forwards with this attitude!
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contain

The contain CSS property allows an author to indicate that an element and its contents are, as much as possible, independent of the rest of the document tree. This allows the browser to recalculate layout, style, paint, size, or any combination of them for a limited area of the DOM and not the entire page, leading to obvious performance benefits.
contain css reference