How to change the underline color of selected tab in angular-material?

Question

I am following tutorial to put md-tabs in the md-toolbar from here. But, My selected indicator tab is same color as the md-primarywhich make it invisible. Please see the image below.

But, when I change the color of the md-tabs to md-accent, it will show the indicator.

How do I change the color of the selected indicator tab?

Here is the code:

<md-toolbar class="md-whiteframe-5dp">
    <div class="md-toolbar-tools">
        <h2>Title</h2>
    </div>

    <md-tabs md-selected="tabs.selectedIndex">
        <md-tab id="tab1" aria-controls="tab1-content">Tab #1</md-tab>
        <md-tab id="tab2" aria-controls="tab2-content">Tab #2</md-tab>
        <md-tab id="tab3" aria-controls="tab3-content">Tab #3</md-tab>
    </md-tabs>
</md-toolbar>

<md-content layout-padding flex>
    <ng-switch on="tabs.selectedIndex" class="tabpanel-container">
        <div role="tabpanel" id="tab1-content" aria-labelledby="tab1" ng-switch-when="0" md-swipe-left="tabs.next()" md-swipe-right="tabs.previous()">
            View for Item #1<br />
            data.selectedIndex = 0
        </div>

    <div role="tabpanel" id="tab2-content" aria-labelledby="tab2" ng-switch-when="1" md-swipe-left="tabs.next()" md-swipe-right="tabs.previous()">
        View for Item #2<br />
        data.selectedIndex = 1
    </div>

    <div role="tabpanel" id="tab3-content" aria-labelledby="tab3" ng-switch-when="2" md-swipe-left="tabs.next()" md-swipe-right="tabs.previous()">
        View for Item #3<br />
        data.selectedIndex = 2
    </div>
    </ng-switch>
</md-content>

By the way, all the color are default.

Answer 1

The simplest way is to change via CSS :

md-tabs.md-default-theme md-ink-bar, md-tabs md-ink-bar {
    color: red !important;
    background-color:red !important;
}

But you can also check the § about theming in the documentation : https://material.angularjs.org/latest/Theming/01_introduction

Sometime the CSS is embedded and generated on the fly in style-tags, if this code doesn't work, try to force the color with !important.