ionic-framework/scss/ionic/structure/_bar.scss

// Use Flexbox for our header and footer bars
.bar {
  @include disable-user-select();

  display: -webkit-box;
  display: box;

  position: fixed;
  left: 0;
  right: 0;
  z-index: 10;
  width: 100%;
  height: $barHeight;
  padding: $barPaddingPortrait;
  box-sizing: border-box;



  // Title inside of a bar is centered
  .title {
    position: absolute;
    z-index: 0;

    top: 0;
    left: 0;
    right: 0;

    line-height: $barHeight;

    margin: 0;
    //padding: $barPaddingVertical 0px;

    min-width: 30px;

    // Go into ellipsis if too small
    text-overflow: ellipsis;

    text-align: center;
    white-space: nowrap;
    font-size: $barTitleFontSize;

  }


  .title a {
    color: inherit;
  }

  .button {
    @include box-flex(0);
    background-color: transparent;
    line-height: $barButtonLineHeight;
    font-size: 12px;
    padding: 4px 12px;
  }

  .button-bar {
    line-height: $barButtonBarLineHeight;
  }

  .button-bar + .button, .button + .button-bar {
    margin-left: 5px;
  }

  // Place the last button in a bar on the right of the bar
  .title + .button:last-child,
  > .button + .button:last-child,
  > .button.pull-right,
  .title + .buttons {
    position: absolute;
    top: 5px;
    right: 5px;
  }
}


// Header at top
.bar-header {
  top: 0;
}

// Footer at bottom
.bar-footer {
  bottom: 0;
}

// Don't render padding if the bar is just for tabs
.bar-tabs {
  padding: 0;
}

.bar-header-secondary {
  top: $barHeight;
}
.bar-footer-secondary {
  bottom: $barHeight;
}

/* Pad top/bottom of content so it doesn't hide behind .bar-title and .bar-tab.
   Note: For these to work, content must come after both bars in the markup */
.has-header {
  top: $barHeight;
}

.has-footer {
  bottom: $barHeight;
}