layer-selection uses more Tailwind

- Tailwind for border radius, same as other elements
- Tailwind for placement

index.css

@@ -95,14 +95,10 @@ a {
 }
 
 #layer-selection {
-    position: absolute;
-    bottom: 1em;
-    left: 1em;
     z-index: 9000;
     background-color: var(--background-color);
     color: var(--foreground-color);
 
-    border-radius: 1em;
     cursor: pointer;
     box-shadow: 0 0 10px var(--shadow-color);
 }
@@ -142,7 +138,6 @@ a {
 }
 
 .layer-selection-toggle {
-    border-radius: 1em;
     display: flex;
     flex-direction: column-reverse;
     background: var(--subtle-detail-color);

index.html

@@ -57,7 +57,7 @@
     <div id="help-button-mobile"></div>
 </div>
 
-<div id="layer-selection"></div>
+<div id="layer-selection" class="absolute bottom-3 left-3 rounded-3xl overflow-hidden"></div>
 
 <div id="centermessage">Loading MapComplete, hang on...</div>