Improve Logo Visibility in Light and Dark Modes (#283)

* Add dark mode support

* fix: improve logo visibility in light and dark themes

This commit addresses two logo visibility issues:
1. User logos are now displayed on a white background in dark theme
   to provide proper contrast
2. Feature icons on the homepage (particularly namespace logo) now
   have a subtle drop shadow to improve visibility against light
   backgrounds

Author: AryanVBW

src/components/HomepageFeatures/styles.module.css

@@ -101,13 +101,13 @@
   border-top:0;
   transform: rotate(150deg);
 }
-
 .imgItem{
   width:auto;
   height:35%;
   margin-bottom:30px;
+  
+  filter: drop-shadow(0px 2px 4px rgba(0, 0, 0, 0.3));
 }
-
 .itemDes{
   width:100%;
   display:flex;

src/components/UserLogos/index.module.css

@@ -17,6 +17,12 @@
     display: flex;
     justify-content: center;
     align-items: center;
+    background-color: #ffffff;
+}
+
+[data-theme='dark'] .link {
+    background-color: #ffffff;
+    border: 1px solid #3a3a3a;
 }
 
 .imgWrapper img {