remove unused/outdated/legacy css file

web/css/app3d-legacy.less

@@ -1,165 +0,0 @@
-@tab-border-color: #2c2c2c;
-@menu-border-radius: 3px;
-@suppressed-color: #888;
-
-.no-selection {
-  user-select: none;
-  -webkit-user-select: none;
-  -moz-user-select: none;
-  -ms-user-select: none;
-}
-
-.history-selected, .history-selected:hover {
-  background-color: #780000;
-}
-
-.button .fa {
-  line-height: 1.5;
-}
-
-.aux-win {
-  color: #fff;
-  background-color: rgba(40,40,40,0.95);
-  border: solid 1px #000;
-  border-radius: @menu-border-radius
-}
-
-.menu {
-  position: absolute;
-  .aux-win;
-  /* this element can't have neither padding nor margin to be properly positioned as menu */
-}
-
-.menu-container {
-  padding: 5px 0 5px 0;
-}
-
-.menu-item {
-  padding: 5px 5px 5px 2px;
-  cursor: pointer;
-  text-transform: capitalize;
-  white-space: nowrap;
-}
-
-.menu-item .menu-text {
-  padding-right: 5px;
-}
-
-.menu-item:hover {
-  background-color: #0074D9;
-}
-
-.menu-flat-bottom {
-  border-radius: @menu-border-radius @menu-border-radius 0 0;
-}
-
-.menu-flat-top {
-  border-radius: 0 0 @menu-border-radius @menu-border-radius;
-}
-
-.menu-separator {
-  border-top: solid 1px #777;
-}
-
-.menu-item .fa {
-  margin-left: -16px;
-  padding-right: 3px;
-}
-
-.action-disabled {
-  color: @suppressed-color - 30;
-}
-
-.menu-item.action-disabled {
-  color: @suppressed-color;
-}
-
-.menu-item .action-hotkey-info {
-  float: right;
-  padding-left: 15px;
-  color: @suppressed-color;
-  font-size: 9px;
-  margin-top: 1px;
-}
-
-.icon16-left {
-  background-position-y: center;
-  background-position-x: 5px;
-  background-repeat: no-repeat;
-  background-size: 16px 16px;
-  padding-left: 25px;
-}
-
-.message-sink {
-  display: none;
-  position: absolute;
-  max-width: 400px;
-  padding: 2px 5px 2px 5px;
-  .aux-win;
-  color: #ccc;
-  white-space: nowrap;
-  z-index: 999;
-}
-
-.action-info > div {
-  padding: 3px 0 3px 0;
-}
-.action-info-hotkey {
- text-align: right;
- font-style: italic;
- color: @suppressed-color;  
-}
-
-.action-info-hint {
-  font-style: italic;
-  color: #E1A4A4;
-}
-
-.solid-list .solid-item {
-  background-image: url('../img/3d/solid32.png');
-}
-
-.solid-list .sketch-item {
-  padding-left : 50px;
-  background-position-x: 30px;
-  background-image: url('../img/3d/sketch32.png');
-}
-
-.modification-item {
-  word-wrap: break-word;
-  word-break: break-all;
-}
-
-.modification-button {
-  line-height: 27px;
-  font-size: 1.3rem;
-  padding: 0 3px 0 3px;
-  &:hover {
-    color: yellowgreen;
-  }
-}
-
-.modification-button.danger {
-  &:hover {
-    color: red;
-  }
-}
-
-.modification-button.action-disabled {
-  &:hover {
-    .action-disabled;
-  }
-}
-
-.modification-right-buttons {
-  display: none;
-}
-
-.history-selected .modification-right-buttons, .modification-item:hover .modification-right-buttons {
-  display: initial;
-}
-
-.errors-message {
-  padding: 5px;
-  color: lightgoldenrodyellow;
-}