feat: add 3D toggle and adjust theme

src/App.css

@@ -23,6 +23,77 @@ footer {
   font-size: x-small;
 }
 
+.controls {
+  z-index: 9;
+  position: absolute;
+  top: 24;
+  left: 24;
+  padding: 16px;
+
+  .control {
+    display: flex;
+    flex-direction: row;
+
+    * {
+      margin: 0 4px;
+    }
+  }
+}
+
+/* The switch - the box around the slider */
+.switch {
+  position: relative;
+  width: 68px;
+  height: 34px;
+}
+
+/* Hide default HTML checkbox */
+.switch input {
+  opacity: 0;
+  width: 0;
+  height: 0;
+}
+
+/* The slider */
+.slider {
+  position: absolute;
+  cursor: pointer;
+  top: 0;
+  left: 0;
+  right: 0;
+  bottom: 0;
+  background-color: #ccc;
+  border-radius: 34px;
+  -webkit-transition: .4s;
+  transition: .4s;
+}
+
+.slider:before {
+  position: absolute;
+  content: "";
+  height: 26px;
+  width: 26px;
+  left: 4px;
+  bottom: 4px;
+  background-color: white;
+  border-radius: 50%;
+  -webkit-transition: .4s;
+  transition: .4s;
+}
+
+input:checked+.slider {
+  background-color: #2196F3;
+}
+
+input:focus+.slider {
+  box-shadow: 0 0 1px #2196F3;
+}
+
+input:checked+.slider:before {
+  -webkit-transform: translateX(26px);
+  -ms-transform: translateX(26px);
+  transform: translateX(26px);
+}
 
 .grey {
   color: #444;