diff --git a/public/index.html b/public/index.html
index 777b9e3..9831c85 100644
--- a/public/index.html
+++ b/public/index.html
@@ -20,6 +20,30 @@
     });
   }catch(_){ }
 
+  // Apply the workspace's saved brand/sidebar theme before first paint, straight from the
+  // localStorage cache. Without this the page briefly shows the hardcoded "Standard Purple"
+  // :root fallback until app-runtime.js's theme module loads and corrects it - a visible
+  // color flash on every load for any workspace that isn't actually using that preset.
+  try{
+    const rawTheme=localStorage.getItem('sunBrandThemeV1');
+    if(rawTheme){
+      const parsed=JSON.parse(rawTheme)||{};
+      const root=document.documentElement.style;
+      const isHex=v=>/^#[0-9a-f]{6}$/i.test(String(v||''));
+      if(parsed.ui&&typeof parsed.ui==='object'){
+        Object.entries(parsed.ui).forEach(([k,v])=>{
+          if(isHex(v))root.setProperty(`--sun-ui-${k.replace(/[A-Z]/g,m=>'-'+m.toLowerCase())}`,v);
+        });
+      }
+      if(parsed.sidebar&&typeof parsed.sidebar==='object'){
+        const sideMap={background:'--sun-sidebar-bg',background2:'--sun-sidebar-bg2',glow:'--sun-sidebar-glow',border:'--sun-sidebar-border',icons:'--sun-sidebar-icons',iconBackground:'--sun-sidebar-icon-bg',text:'--sun-sidebar-text',muted:'--sun-sidebar-muted',activeBackground:'--sun-sidebar-active-bg',activeText:'--sun-sidebar-active-text',activeIcon:'--sun-sidebar-active-icon',indicator:'--sun-sidebar-indicator',toolsBackground:'--sun-sidebar-tools-bg',toolsBorder:'--sun-sidebar-tools-border',collapseBackground:'--sun-sidebar-collapse-bg',collapseText:'--sun-sidebar-collapse-text',badgeBackground:'--sun-sidebar-badge-bg',badgeText:'--sun-sidebar-badge-text'};
+        Object.entries(sideMap).forEach(([k,cssVar])=>{
+          if(isHex(parsed.sidebar[k]))root.setProperty(cssVar,parsed.sidebar[k]);
+        });
+      }
+    }
+  }catch(_){ }
+
   window.sunFetchWithTimeout=window.sunFetchWithTimeout||async function(url,options={},timeout=8000){
     const controller=new AbortController();
     const timer=setTimeout(()=>controller.abort(),Math.max(1000,Number(timeout)||8000));