✨ Closed #108, add animated transition when expand and collapse code block.

assets/css/_common/scaffolding/highlight/copy-code.scss

@@ -38,6 +38,7 @@
       line-height: 1;
       text-rendering: auto;
       padding-right: .25rem;      
+      transition: content 1s ease-in-out;
       
       &::before {
         content: "\f102";
@@ -61,9 +62,18 @@
 
   > .chroma {
     position: relative;
+    max-height: 500px;
+    opacity: 1;
+    visibility: visible;
+    transition: max-height 0.8s ease-in-out, opacity 0.7s ease-in-out; 
 
     &.hidden-code {
-      display: none;
+      max-height: 0;
+      opacity: 0;
+      visibility: hidden;
+
+      animation-name: slideInUp;
+      animation-duration: 1s;
     }
     
     pre {

assets/js/3rd/others/clipboard.js

@@ -18,8 +18,7 @@ NexT.plugins.others.clipboard = function () {
 
       element.addEventListener('mouseleave', () => {
         setTimeout(() => {
-          copyBtn.classList.remove('copied');
-          copyBtn.classList.remove('copieduncopied');
+          copyBtn.classList.remove('copied','uncopied');
         }, 300);
       });