feat: 首页改版

src/styles/global.css

@@ -2,12 +2,24 @@
 @import "css-reset.css";
 
 :root {
-  --layout-width: 980px;
-  --background: #ffffff;
+  --layout-width: 1080px;
+  --background: #f6f7f9;
+  --shadow: 0 2px 8px rgba(0, 0, 0, 0.06);
+  --shadow-hover: 0 8px 24px rgba(0, 0, 0, 0.10);
+  --card-bg: #ffffff;
+  --text: #2b2f36;
+  --text-secondary: #6b7280;
+  --border: #e5e7eb;
+  --primary: #2b2f36;
 }
 
 .dark {
   --background: #0a0a0a;
+  --card-bg: #161b22;
+  --text: #2b2f36;
+  --text-secondary: #e5e7eb;
+  --border: #e5e7eb;
+  --primary: #3d414a;
 }
 
 html,
@@ -18,7 +30,7 @@ body {
 }
 
 html {
-  background: #f8fafc;
+  background: var(--background);
 }
 
 html.dark {
@@ -37,6 +49,8 @@ main {
   width: 100%;
   margin: 0 auto;
   padding: 32px;
+  display: flex;
+  flex-direction: column;
 }
 
 @media (max-width: 768px) {