Angular 6定义全局scss标题样式-Bootstrap

Question

I am trying to overwrite and define global heading styles for my Angular 6 application. If I do something like this in the styles.scss file, it works!

$h1-font-size: 50px;

but when I try to define $h1-font-size based on a screen size(media queries) it doesn't show the right font size, I have something like this ATM:

// screen size breakpoints

$grid-breakpoints: (
  xs: 0,
  sm: 576px,
  md: 768px,
  lg: 992px,
  xl: 1200px
);

// media queries xs, md and lg
@media only screen and (min-width: map-get($grid-breakpoints, xs)) {
    $h1-font-size: 12px;
}

@media only screen and (min-width: map-get($grid-breakpoints, md)) {
    $h1-font-size: 18px;
}

@media only screen and (min-width: map-get($grid-breakpoints, lg)) {
    $h1-font-size: 50px;
}

angular.json:

  "styles": [
              "node_modules/bootstrap/dist/css/bootstrap-reboot.css",
              "node_modules/bootstrap/dist/css/bootstrap-grid.css",
              "src/styles.scss",
              ...
            ],

bootstrap-scss._variables.scss file: scss file

$h1-font-size:                $font-size-base * 2.5 !default;
$h2-font-size:                $font-size-base * 2 !default;
$h3-font-size:                $font-size-base * 1.75 !default;
$h4-font-size:                $font-size-base * 1.5 !default;
$h5-font-size:                $font-size-base * 1.25 !default;
$h6-font-size:                $font-size-base !default;

styles.scss file:

/* You can add global styles to this file, and also import other style files */

@import '~bootstrap/scss/bootstrap-reboot';
@import '~bootstrap/scss/bootstrap-grid';
// Required
@import "~node_modules/bootstrap/scss/bootstrap";

/* Set global default font family */
$font-family-base: 'Source Sans Pro',
sans-serif;
body,
html {
    font-family: $font-family-base
}

$grid-breakpoints: ( xs: 0, sm: 576px, md: 768px, lg: 992px, xl: 1200px);
@media only screen and (min-width: map-get($grid-breakpoints, xs)) {
    $h1-font-size: 12px;
}

@media only screen and (min-width: map-get($grid-breakpoints, md)) {
    $h1-font-size: 12px;
}

@media only screen and (min-width: map-get($grid-breakpoints, lg)) {
    $h1-font-size: 50px;
}

Is it even possible? What's the best practice to overwrite boostrap-scss headings based on the screen size?

Link to the stackblitz example - https://stackblitz.com/edit/angular-scss-global-headings

Answer 1

The problem is that you assign a new vlaue to a variable depends on screen size but you never use it. Just select h1 and set a value. It worked with your stackblitz example

@media only screen and (min-width: map-get($grid-breakpoints, xs)) {
    $h1-font-size: 10px;
    h1 {
      font-size: $h1-font-size
      }
}

@media only screen and (min-width: map-get($grid-breakpoints, md)) {
    $h1-font-size: 30px;
    h1 {
      font-size: $h1-font-size
      }
}

@media only screen and (min-width: map-get($grid-breakpoints, lg)) {
    $h1-font-size: 50px;
    h1 {
      font-size: $h1-font-size
      } 
}