The AMP HTML friendly: Do not use the `!important` qualifier

[ENDOH takanao]

Can not use the !important qualifier in the AMP HTML site.

https://www.ampproject.org/docs/reference/spec.html#important

Usage of the !important qualifier is not allowed. This is a necessary requirement to enable AMP to enforce its element sizing invariants.

https://github.com/cutestrap/cutestrap/blob/d9985d1/src/sass/support/_base.scss#L286

/* remove yellow from chrome auto-fill background */
input:-webkit-autofill,
textarea:-webkit-autofill,
select:-webkit-autofill {
  color: $gray1;
  -webkit-text-fill-color: $gray1;
  -webkit-box-shadow: 0 0 0px 1000px white inset !important;
}

[Tyler Childs]

Done in 2.0