Bootstrap/scss/_popover.scss

//
// Popovers
// --------------------------------------------------


.popover {
  position: absolute;
  top: 0;
  left: 0;
  z-index: $zindex-popover;
  display: none;
  max-width: $popover-max-width;
  padding: 1px;
  // Reset font and text properties given new insertion method
  font-family: $font-family-base;
  font-size: $font-size-base;
  font-weight: normal;
  line-height: $line-height-base;
  text-align: left;
  // Overrides for proper insertion
  white-space: normal;
  background-color: $popover-bg;
  background-clip: padding-box;
  border: 1px solid $popover-border-color;
  @include border-radius($border-radius-lg);
  @include box-shadow(0 5px 10px rgba(0,0,0,.2));
}

// Offset the popover to account for the popover arrow
.popover-top     { margin-top: -$popover-arrow-width; }
.popover-right   { margin-left: $popover-arrow-width; }
.popover-bottom  { margin-top: $popover-arrow-width; }
.popover-left    { margin-left: -$popover-arrow-width; }

.popover-title {
  padding: 8px 14px;
  margin: 0; // reset heading margin
  font-size: $font-size-base;
  background-color: $popover-title-bg;
  border-bottom: 1px solid darken($popover-title-bg, 5%);
  @include border-radius(($border-radius-lg - 1) ($border-radius-lg - 1) 0 0);
}

.popover-content {
  padding: 9px 14px;
}

// Arrows
//
// .popover-arrow is outer, .popover-arrow:after is inner

.popover-arrow {
  &,
  &:after {
    position: absolute;
    display: block;
    width: 0;
    height: 0;
    border-color: transparent;
    border-style: solid;
  }
}
.popover-arrow {
  border-width: $popover-arrow-outer-width;
}
.popover-arrow:after {
  content: "";
  border-width: $popover-arrow-width;
}

.popover-top > .popover-arrow {
  bottom: -$popover-arrow-outer-width;
  left: 50%;
  margin-left: -$popover-arrow-outer-width;
  border-top-color: $popover-arrow-outer-color;
  border-bottom-width: 0;
  &:after {
    bottom: 1px;
    margin-left: -$popover-arrow-width;
    content: "";
    border-top-color: $popover-arrow-color;
    border-bottom-width: 0;
  }
}
.popover-right > .popover-arrow {
  top: 50%;
  left: -$popover-arrow-outer-width;
  margin-top: -$popover-arrow-outer-width;
  border-right-color: $popover-arrow-outer-color;
  border-left-width: 0;
  &:after {
    bottom: -$popover-arrow-width;
    left: 1px;
    content: "";
    border-right-color: $popover-arrow-color;
    border-left-width: 0;
  }
}
.popover-bottom > .popover-arrow {
  top: -$popover-arrow-outer-width;
  left: 50%;
  margin-left: -$popover-arrow-outer-width;
  border-top-width: 0;
  border-bottom-color: $popover-arrow-outer-color;
  &:after {
    top: 1px;
    margin-left: -$popover-arrow-width;
    content: "";
    border-top-width: 0;
    border-bottom-color: $popover-arrow-color;
  }
}

.popover-left > .popover-arrow {
  top: 50%;
  right: -$popover-arrow-outer-width;
  margin-top: -$popover-arrow-outer-width;
  border-right-width: 0;
  border-left-color: $popover-arrow-outer-color;
  &:after {
    right: 1px;
    bottom: -$popover-arrow-width;
    content: "";
    border-right-width: 0;
    border-left-color: $popover-arrow-color;
  }
}