vue-material-kit/src/assets/scss/material-kit/_utilities-extend.scss

@each $name, $value in $max-width-dim {
  .max-width-#{$name} {
    max-width: $value !important;
  }
}

@each $name, $value in $width-dim {
  .width-#{$name} {
    width: $value !important;
  }
}