fix(navbar): replace logo image with text label in the navbar

Author: httpdss

site/index.html

@@ -114,7 +114,7 @@
   <nav class="navbar">
     <div class="container navbar-content">
       <div class="navbar-brand">
-        <img src="/struct/images/logo.png" alt="STRUCT Logo" class="navbar-logo">
+        STRUCT:
       </div>
       <ul class="navbar-nav">
         <li><a href="#features">Features</a></li>