chrome/browser/resources/ntp/most_visited.css

/* Most Visited */

#most-visited {
  position: relative;
  padding: 0;
  height: 366px;
  margin-top: -10px;
  -webkit-user-select: none;
}

.thumbnail-container {
  position: absolute;
  color: hsl(213, 90%, 24%);
  text-decoration: none;
  -webkit-transition: left .15s, right .15s, top .15s;
  text-decoration: none;
}

.thumbnail-container:focus {
  outline: none;
}

.thumbnail,
.thumbnail-container > .title {
  width: 207px; /* natural size is 196 */
  height: 129px; /* 136 */
  -webkit-transition: width .15s, height .15s;
}

.thumbnail-container > .title {
  line-height: 16px;
  height: 16px;
  margin: 0;
  margin-top: 4px;
  font-size: 100%;
  font-weight: normal;
  padding: 0 3px;
  opacity: 1;
  -webkit-transition: opacity .15s, width .15s;
  color: black;
}

.thumbnail-wrapper {
  display: block;
  background-size: 212px 132px;
  background: no-repeat 4px 4px;
  background-color: white;
  border-radius: 5px;
  -webkit-transition: background-size .15s;
  position: relative;
}

.filler * {
  visibility: hidden;
}

.filler {
  pointer-events: none;
}

.filler .thumbnail-wrapper {
  visibility: visible;
  border: 3px solid hsl(213, 60%, 92%);
}

.filler .thumbnail {
  visibility: inherit;
  border: 1px solid white;
  padding: 0;
  background-color: hsl(213, 60%, 92%);
}

.edit-bar {
  display: -webkit-box;
  -webkit-box-orient: horizontal;
  -webkit-box-align: stretch;
  padding: 3px;
  padding-bottom: 0;
  height: 17px; /* 23 - 2 * 3 */
  cursor: move;
  font-size: 100%;
  line-height: 17px;
  background: hsl(213, 54%, 95%);
  border-top-left-radius: 4px;
  border-top-right-radius: 4px;
  position: relative;
  margin-top: 21px;
  margin-bottom: -21px;
  -webkit-transition: margin .15s, background .15s;
}

.edit-bar > * {
  display: block;
  position: relative;
}

.thumbnail-container:focus .edit-bar,
.thumbnail-container:hover .edit-bar {
  margin-top: 0;
  margin-bottom: 0;
  -webkit-transition-delay: .5s, 0s;

  /* We need background-color as well to get the fade out animation correct */
  background-color: hsl(213, 66%, 57%);
  background-image: -webkit-gradient(linear, left top, left bottom,
                                     from(hsl(213, 87%, 67%)),
                                     to(hsl(213, 66%, 57%)));
}

.edit-bar > .spacer {
  -webkit-box-flex: 1;
}

.edit-bar > .pin,
.edit-bar > .remove {
  width: 16px;
  height: 16px;
  cursor: pointer;
  background-image: no-repeat 50% 50%;
}

.edit-bar > .pin {
  background-image: url('ntp_pin_off.png');
}

.edit-bar > .pin:hover {
  background-image: url('ntp_pin_off_h.png');
}

.edit-bar > .pin:active {
  background-image: url('ntp_pin_off_p.png');
}

.pinned .edit-bar > .pin {
  background-image: url('ntp_pin_on.png');
}

.pinned .edit-bar > .pin:hover {
  background-image: url(ntp_pin_on_h.png');
}

.pinned .edit-bar > .pin:active {
  background-image: url(ntp_pin_on_p.png');
}

.edit-bar > .remove {
  background-image: url('ntp_close.png');
}

.edit-bar > .remove:hover {
  background-image: url('ntp_close_h.png');
}

.edit-bar > .remove:active {
  background-image: url('ntp_close_p.png');
}

.thumbnail-container > .title > div {
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  background: no-repeat 0 50%;
  background-size: 16px;
  padding-left: 20px; /* we cannot use padding start here because even if we set
                         the direction we always want the icon on the same side
                      */
  padding-right: 0;
}

html[dir=rtl] .thumbnail-container > .title > div {
  background-position-x: 100%;
  padding-left: 0;
  padding-right: 20px;
  text-align: right;
}

.thumbnail {
  border: 3px solid hsl(213, 63%, 93%);
  padding: 1px;
  border-radius: 5px;
  display: block;
  -webkit-box-shadow: 0px 2px 2px hsla(0, 0%, 0%, 0);
  -webkit-transition: width .15s, height .15s, border-color .15s,
      border-top-left-radius .15s, border-top-right-radius .15s,
      -webkit-box-shadow .15s;
}

.edit-mode-border {
  border-radius: 4px;

  /* when dragged over we move this */
  position: relative;
  -webkit-transition: top .15s, left .15s;
}

.thumbnail-container:focus .thumbnail,
.thumbnail-container:hover .thumbnail {
  border-color: hsl(213, 66%, 57%);
  -webkit-box-shadow: 0px 2px 2px hsla(0, 0%, 0%, 0);
  -webkit-border-top-left-radius: 0;
  -webkit-border-top-right-radius: 0;

  background-image: -webkit-gradient(linear, left top, left bottom,
    from(hsla(0, 0%, 0%, 0)),
    color-stop(0.85, hsla(0, 0%, 47%, 0)),
    to(hsla(0, 0%, 47%, 0.2))
    );

  /* delay border radius transition as much as the edit bar slide delay */
  -webkit-transition-delay: 0, 0, 0, .5s, .5s, 0;
}

.thumbnail-container:focus > .edit-mode-border,
.thumbnail-container:hover > .edit-mode-border {
  background-color: hsl(213, 66%, 57%);
  -webkit-box-shadow: 0px 2px 2px hsla(0, 0%, 0%, .5);
}

.dragging,
.dragging * {
  -webkit-transition: none !important;
}

.dragging > .title {
  opacity: 0;
}

@-webkit-keyframes 'fade-in' {
  0% {
    opacity: 0;
  }

  100% {
    opacity: 1;
  }
}

.fade-in {
  -webkit-animation: 'fade-in' .15s;
}

@media (max-width: 940px) {
  #most-visited {
    height: 294px;
  }

  .thumbnail,
  .thumbnail-container > .title {
    width: 150px;
    height: 93px;
  }

  .thumbnail-container > .title {
    height: auto;
  }

  .thumbnail-wrapper {
    background-size: 150px 93px;
  }
}