feat(theme-default): enhance color transitions (#321)

Author: ilharp

packages/@vuepress/plugin-search/src/client/styles/search.css

@@ -16,7 +16,7 @@
   line-height: 2rem;
   padding: 0 0.5rem 0 2rem;
   outline: none;
-  transition: all 0.2s ease;
+  transition: all ease 0.3s;
   background: var(--search-bg-color) url('search.svg') 0.6rem 0.5rem no-repeat;
   background-size: 1rem;
 }

packages/@vuepress/theme-default/src/client/styles/home.scss

@@ -70,6 +70,7 @@
 
   .features {
     border-top: 1px solid var(--c-border);
+    transition: border-top ease 0.3s;
     padding: 1.2rem 0;
     margin-top: 2.5rem;
     display: flex;

packages/@vuepress/theme-default/src/client/styles/layout.scss

@@ -34,7 +34,8 @@
   scrollbar-width: thin;
   scrollbar-color: var(--c-brand) var(--c-border);
   background-color: var(--c-bg-sidebar);
-  transition: background-color ease 0.3s, border-right-color ease 0.3s;
+  transition: transform ease 0.3s, background-color ease 0.3s,
+    border-right-color ease 0.3s;
   &::-webkit-scrollbar {
     width: 7px;
   }
@@ -160,7 +161,6 @@ h6 {
     top: 0;
     padding-top: var(--navbar-height);
     transform: translateX(-100%);
-    transition: transform 0.2s ease;
   }
 
   .page {

packages/@vuepress/theme-default/src/client/styles/normalize.scss

@@ -48,9 +48,7 @@ code {
   background-color: var(--c-bg-light);
   border-radius: 3px;
   overflow-wrap: break-word;
-  transition:
-    background-color ease 0.3s,
-    color ease 0.3s;
+  transition: background-color ease 0.3s, color ease 0.3s;
 }
 
 blockquote {

packages/@vuepress/theme-default/src/client/styles/page.scss

@@ -59,6 +59,7 @@
     min-height: 2rem;
     margin-top: 0;
     border-top: 1px solid var(--c-border);
+    transition: border-top ease 0.3s;
     padding-top: 1rem;
     overflow: auto;
   }

packages/@vuepress/theme-default/src/client/styles/sidebar.scss

@@ -14,6 +14,7 @@
   .navbar-links {
     display: none;
     border-bottom: 1px solid var(--c-border);
+    transition: border-bottom-color ease 0.3s;
     padding: 0.5rem 0 0.75rem 0;
 
     a {