[BEAM-14311] [Website] Home Page Improvements - Margins & Width

[bullet03]

[BEAM-14311]

• change width of h1 and h2 in header section
• change space (margin and padding) between sections

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Can one of the admins verify this patch?

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Can one of the admins verify this patch?

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Can one of the admins verify this patch?

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Can one of the admins verify this patch?

[bullet03]

R: @AydarZaynutdinov

[dariabezkorovaina]

@bullet03 got some feedback, please reduce the whitespace between sections even more (for How Does It Work section: ~ margin-top: 20px, margin-bottom: 30px) and the rest of the sections should have the same margins, too.

[nausharipov]

LGTM.

[dariabezkorovaina]

@pcoet can you please approve these minor changes, too?
Reduced whitespaces and adjusted header section as per Aizhamal's request.

[dariabezkorovaina]

@pabloem and this PR #17388 is to be merged AFTER #17444 is merged (#17444 should be merged first), please help with this one, too, if you can:)

[pabloem]

lgtm thanks!