[css-grid-1][css-grid-2] Replace article to main

[SiarheiBobryk]

Use main as a more suitable element in example 9.

Changes:

• Tweak the SVG image
• Use the main element in example 9 for CSS Grid Layout Module Level
  1 and CSS Grid Layout Module Level 2

Before:

After:

[tabatkins]

I'm fine with this change, but it looks like you did the SVG edits in a WYSIWIG editor, which totally trashed the file with metadata; I can't merge that. The SVG should be readable and easily editable by hand, so you can swap out just the one offending word; it uses proper centered positioning, so you won't even need to adjust the position of anything.

[SiarheiBobryk]

Thanks for your feedback @tabatkins!
I've used Inkscape for that. Please, could you suggest to me the best SVG editor (your opinion)?

[SiarheiBobryk]

so you can swap out just the one offending word;

@tabatkins it's done!

[SiarheiBobryk]

@tabatkins please check