paper-gtk-theme/Paper/gtk-3.18/apps/_unity.scss

/********
* Unity *
*********/

$unity_color: #546e7a; /* Unity window border color */
$backdrop_unity_color: darken($unity_color,10%); /* Backdrop Unity window border color */
$unity_text_color: #dbdee0; /* Unity window text color */
$backdrop_unity_text_color: darken($unity_text_color,10%); /* Backdrop Unity window text color */
$unity_panel_color: darken($unity_color, 20%); /* Unity panel color #454D50 */
$backdrop_unity_panel_color: darken($unity_panel_color, 10%); /* Backdrop Unity panel color */

UnityDecoration {

  /* Border properties (top, right, bottom, left) */
  -UnityDecoration-extents: 28px 1px 1px 1px;/* the size of the decorations  */
  -UnityDecoration-input-extents: 10px;/* the extra size of the input areas */

  /* Shadows settings */
  -UnityDecoration-shadow-offset-x: 1px;/* Size property, the shadow x offset */
  -UnityDecoration-shadow-offset-y: 1px;/* Size property, the shadow y offset */
  -UnityDecoration-active-shadow-color: rgba (0, 0, 0, 0.647);/* Color property, active window shadow color */
  -UnityDecoration-active-shadow-radius: 8px;/* Size property, active window shadow radius */
  -UnityDecoration-inactive-shadow-color: rgba (0, 0, 0, 0.647);/* Color property, inactive windows shadow color */
  -UnityDecoration-inactive-shadow-radius: 5px;/* Size property, inactive windows shadow radius */

  /* Glow applied to the selected scaled window */
  -UnityDecoration-glow-size: 8px;/* Size property, size of glow */
  -UnityDecoration-glow-color: $selected_bg_color;/* Color property of the glow */

  /* Title settings */
  -UnityDecoration-title-indent: 10px;/* Size property, left indent of the title */
  -UnityDecoration-title-fade: 35px;/* Size property, space of the title that can be faded */
  -UnityDecoration-title-alignment: 0.0;/* Float from 0.0 to 1.0, to align the title */
  background-color: $unity_color;
  color: $unity_text_color;

  .top {
    padding: 0 5px 0 5px;
    border-radius: 4px 4px 0px 0px;
    box-shadow: none;
    border: 1px solid $unity_color;
    border-bottom-width: 0;
    background-color: $unity_color;
    color: $unity_text_color;
    border-top: 1px solid rgba(255,255,255,0.1);

    &:backdrop {
      border-bottom-width: 0;
      background-color: $backdrop_unity_color;
      color: $backdrop_unity_text_color;
      border-top: 1px solid rgba(255,255,255,0.1);
    }

    .menuitem {
      color: $unity_text_color;

      &:backdrop {
        background-color: $backdrop_unity_color;
        color: $backdrop_unity_text_color;
      }
    }
  }
}


UnityDecoration.left,
UnityDecoration.right {
  background-repeat: repeat-x;
  background-color: darken($unity_color, 0.6);
  background-size: 1px 120px;
  background-clip: border-box;
  background-image: linear-gradient(to bottom, 
                                    $unity_color,
                                    darken($unity_color, 0.6)
                                    );
}

UnityDecoration.bottom {
  background-size: 1px;
  background-repeat: repeat-x;
  background-color: darken($unity_color, 0.6);
}

UnityDecoration.left:backdrop,
UnityDecoration.right:backdrop,
UnityDecoration.bottom:backdrop {
  background-size: 1px;
  background-repeat: repeat-x;
  background-color: $backdrop_unity_color;
}


/**************
* Unity Panel *
***************/

UnityPanelWidget,
.unity-panel {
background-color: $unity_panel_color;
color: $unity_text_color;
}


UnityPanelWidget:backdrop,
.unity-panel:backdrop {
  background-color: $backdrop_unity_panel_color;
  color: $backdrop_unity_text_color;
}

.unity-panel.menuitem,
.unity-panel .menuitem {
  border-width: 0 1px;
  color: $unity_text_color;
}

.unity-panel.menubar,
.unity-panel .menubar {
  color: $unity_text_color;
}

.unity-panel.menu.menubar,
.unity-panel .menu .menubar {
  background-color: $unity_panel_color;
  color: $unity_text_color;
}

.unity-panel.menubar:backdrop,
.unity-panel .menubar *:backdrop {
  color: $backdrop_fg_color;
}

.unity-panel.menubar.menuitem,
.unity-panel.menubar .menuitem {
  padding: 3px 5px;
  border-width: 1px;
  border-style: solid;
  border: none;
  background: none;
  color: $unity_text_color;
  box-shadow: none;
}

.unity-panel.menubar.menuitem:hover,
.unity-panel.menubar .menuitem:hover {
  border-radius: 0;
  background-color: darken($unity_color, 1.05);
  color: $unity_text_color;
  box-shadow: none;
}

.unity-panel.menubar .menuitem *:hover {
  color: white;
  box-shadow: none;
}

.unity-panel.menubar .menuitem.separator,
.unity-panel.menubar.menuitem.separator {
  -GtkMenuItem-horizontal-padding: 0;
  -GtkWidget-separator-height: 1;
  border: none;
  color: $borders_color;
}

/* Force Quit */
SheetStyleDialog.unity-force-quit {
   background-color: $base_color;
}


@keyframes playbackmenuitem_spinner {
  to { -gtk-icon-transform: rotate(1turn); }
}

.menu IdoPlaybackMenuItem.menuitem:active {
  -gtk-icon-source: -gtk-icontheme("process-working-symbolic");
  animation: playbackmenuitem_spinner 1s infinite linear;
  color: $selected_bg_color;
}