fix: center pile

src/styles/components/_challenges.scss

@@ -296,8 +296,11 @@
   display: flex;
   flex-direction: row;
   justify-content: center;
-  margin-top: 1rem;
+  margin-top: 3rem;
   width: 100%;
+  @media #{$large-phone} {
+    margin-top: 1rem;
+  }
   .day-solo {
     display: flex;
     flex-direction: column;
@@ -353,6 +356,7 @@
   display: flex;
   flex-direction: row;
   align-items: center;
+  justify-content: center;
   width: 100%;
   .pile-section {
     display: grid;
@@ -479,7 +483,10 @@
         max-width: 53rem;
         &.--ongoing {
           @extend .cp-valid;
-          width: 60%;
+          width: 25%;
+          @media #{$large-phone} {
+            width: 60%;
+          }
         }
         .cp-left-button {
           margin-right: 0.25rem;