change theme from purple to blue

pdb-js/src/custom-theme.scss

@@ -0,0 +1,24 @@
+@import '~@angular/material/theming';
+// Plus imports for other components in your app.
+
+// Include the common styles for Angular Material. We include this here so that you only
+// have to load a single css file for Angular Material in your app.
+// Be sure that you only ever include this mixin once!
+@include mat-core();
+
+// Define the palettes for your theme using the Material Design palettes available in palette.scss
+// (imported above). For each palette, you can optionally specify a default, lighter, and darker
+// hue. Available color palettes: https://material.io/design/color/
+$candy-app-primary: mat-palette($mat-blue);
+$candy-app-accent:  mat-palette($mat-blue, A200, A100, A400);
+
+// The warn palette is optional (defaults to red).
+$candy-app-warn:    mat-palette($mat-red);
+
+// Create the theme object (a Sass map containing all of the palettes).
+$candy-app-theme: mat-light-theme($candy-app-primary, $candy-app-accent, $candy-app-warn);
+
+// Include theme styles for core and each component used in your app.
+// Alternatively, you can import and @include the theme mixins for each component
+// that you are using.
+@include angular-material-theme($candy-app-theme);