style: update border-radius and padding values across components

- standardize border-radius from 8px to 6px for consistent styling
- adjust padding values from 1rem to 0.75rem for better visual hierarchy
- remove redundant overflow-y properties for cleaner code

docs/.vitepress/theme/components/appendix/browser-devtools/BrowserDevToolsDemo.vue

@@ -1523,7 +1523,7 @@ onUnmounted(() => {
 }
 .console-output {
   flex: 1;
-  overflow-y: auto;
+  
   font-family: Consolas, 'Lucida Console', monospace;
   font-size: 11px;
 }

docs/.vitepress/theme/components/appendix/browser-devtools/BrowserDevToolsLiveDemo.vue

@@ -400,7 +400,7 @@ const selectNode = (node) => {
 /* Virtual Page Preview */
 .virtual-page-container {
   border: 1px solid #d0d7de;
-  border-radius: 8px;
+  border-radius: 6px;
   overflow: hidden;
   background: #fff;
   box-shadow: 0 4px 12px rgba(0, 0, 0, 0.08);
@@ -471,7 +471,7 @@ const selectNode = (node) => {
 /* DevTools Simulator (Enhanced) */
 .browser-devtools-demo {
   border: 1px solid #d0d7de;
-  border-radius: 8px;
+  border-radius: 6px;
   background-color: #ffffff;
   color: #202124;
   font-family: 'Segoe UI', '.SFNSDisplay', 'Roboto', sans-serif;

docs/.vitepress/theme/components/appendix/browser-devtools/DevToolsConsoleDemo.vue

@@ -152,7 +152,7 @@ const runShortcut = (cmd) => {
 
 .console-body {
   height: 250px;
-  overflow-y: auto;
+  
   background-color: #f5f7fa;
   border: 1px solid #e4e7ed;
   border-radius: 4px;

docs/.vitepress/theme/components/appendix/browser-devtools/DevToolsElementsDemo.vue

@@ -154,7 +154,7 @@ const updateStyle = (prop, value) => {
 
 .dom-content, .style-content {
   padding: 10px;
-  overflow-y: auto;
+  
   flex: 1;
 }
 

docs/.vitepress/theme/components/appendix/browser-devtools/DevToolsSourcesDemo.vue

@@ -311,7 +311,7 @@ const flatNext = () => {
 .code-area {
   flex: 2;
   background: #f5f7fa;
-  overflow-y: auto;
+  
   font-family: monospace;
   border-right: 1px solid #dcdfe6;
 }