update home logo and backgroud

Author: cywang1905

docs/assets/cover/wall-page-8.jpg

@@ -10,7 +10,7 @@ extra_css:
 theme:
   name: material
   language: zh
-  logo: assets/slime-logo.png
+  logo: assets/slime-logo-home.png
   favicon: assets/todo.png
   custom_dir: overrides
   icon:

docs/assets/cover/wall-page-9.jpg

@@ -6,7 +6,7 @@
   <section class="home-container">
     <div class="background"></div>
     <div class="animated-gradient">
-      <img src="assets/cover/wall-page-3.jpg" style="display: none;"/>
+      <img src="assets/cover/wall-page-8.jpg" style="display: none;"/>
     </div>
     <div class="md-grid md-typeset">
       <div class="mdx-hero" style="margin-top:-100px">