Good to know about Bootstrap

• Container

  Whatever is enclosed inside <div class="container"></div> will be restricted to the same width as the rest of the Web page.

• Material Design

  Indeed, If you have interest where I found this colors you can visit www.android.com and then look up their documentation for material design and there, they have suggestions for how colors can be used in your Android application but the same thing applies even to a website.

• Column classes

  • col, col-x, col-auto
  • col-xx-x
  • order-xx-first/last
  • offset-xx-x

• Button class btn-block