docs: fix the display of the mobile menu. (#570)

Signed-off-by: yuluo-yx <[email protected]>

Author: yuluo-yx

website/src/components/ScrollToTop/styles.module.css

@@ -45,7 +45,7 @@
   box-shadow: 0 8px 20px rgba(88, 166, 255, 0.5);
 }
 
-@media (max-width: 768px) {
+@media (max-width: 996px) {
   .scrollToTop {
     bottom: 1.5rem;
     right: 1.5rem;
@@ -54,6 +54,15 @@
   }
 }
 
+@media (max-width: 768px) {
+  .scrollToTop {
+    bottom: 5rem;
+    right: 1rem;
+    width: 45px;
+    height: 45px;
+  }
+}
+
 .scrollToTop::before {
   content: '';
   position: absolute;