feat(ui): LESS Integration

#15-Create-a-default-theme-with-Less- (#23)
Added LESS and created a light mode

Co-authored-by: LQ63 <lkhermann@web.de>
Reviewed-on: #23
Reviewed-by: Janis <janis-e@gmx.de>
Co-authored-by: lq64 <lq@blackhole.local>
Co-committed-by: lq64 <lq@blackhole.local>

knockoutwhistweb/public/stylesheets/main.css

@@ -1,102 +0,0 @@
-body {
-    background-image: url("/assets/images/background.png");
-}
-
-html, body {
-    height: 100vh;
-    margin: 0;
-}
-#sessions {
-    display: flex;
-    flex-direction: column;
-    justify-content: flex-start;
-    align-items: center;
-    text-align: center;
-}
-
-#sessions a, h1, p {
-    color: white;
-    font-size: 40px;
-    font-family: Arial;
-}
-#ingame {
-    display: flex;
-    flex-direction: column;
-    align-items: center;
-    justify-content: flex-end;
-    height: 100%;
-}
-#playercards {
-    display: flex;
-    flex-direction: row;
-    justify-content: center;
-    height: 20%
-}
-#cardsplayed {
-    display: flex;
-    flex-direction: row;
-    height: 10%;
-    min-height: 10%
-}
-#playedcardplayer {
-    display: flex;
-    flex-direction: column;
-    justify-content: flex-end;
-}
-#playedcardplayer p {
-    font-size: 12px;
-    height: 4%;
-}
-#playedcardplayer img {
-    height: 90%;
-}
-
-#firstCard {
-    display: flex;
-    flex-direction: row;
-    height: 20%;
-    width: 100%;
-    justify-content: space-between;
-}
-#firstCardObject {
-    display: flex;
-    flex-direction: column;
-    margin-right: 4%;
-}
-#firstCardObject img{
-    height: 90%;
-}
-#firstCardObject p{
-    height: 10%;
-    font-size: 20px;
-
-}
-#trumpsuit {
-    display: flex;
-    flex-direction: row;
-    margin-left: 4%;
-}
-#nextPlayers {
-    display: flex;
-    flex-direction: column;
-    align-items: center;
-    height: 0%;
-}
-#nextPlayers p {
-    margin-top: 0px;
-    margin-bottom: 0px;
-}
-#invisible {
-    visibility: hidden;
-}
-#selecttrumpsuit {
-    display: flex;
-    flex-direction: column;
-    align-items: center;
-    height: 100%;
-}
-#rules {
-    color: white;
-    font-size: 1.5em;
-    font-family: Arial;
-}