diff --git a/apps/web_v1/public/favicon.svg b/apps/web_v1/public/favicon.svg
deleted file mode 100644
index e88854d..0000000
--- a/apps/web_v1/public/favicon.svg
+++ /dev/null
@@ -1,10 +0,0 @@
-<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 128 128" role="img" aria-labelledby="title">
-  <title id="title">森林AI</title>
-  <rect x="4" y="4" width="120" height="120" rx="28" fill="#165DFF"/>
-  <path d="M64 23C43 23 27 40 27 61c0 13 7 24 17 30h40c10-6 17-17 17-30 0-21-16-38-37-38Z" fill="#F4F8FF"/>
-  <path d="M64 99V65M64 76 47 61M64 82l18-16M64 68l12-13" fill="none" stroke="#F4F8FF" stroke-linecap="round" stroke-linejoin="round" stroke-width="10"/>
-  <path d="M42 58c6-15 29-22 45-7M39 69c12-11 38-13 50 2M48 78c9-5 24-6 33-1" fill="none" stroke="#165DFF" stroke-linecap="round" stroke-width="5"/>
-  <circle cx="47" cy="61" r="6" fill="#14B8A6"/>
-  <circle cx="76" cy="55" r="6" fill="#60A5FA"/>
-  <circle cx="82" cy="66" r="6" fill="#A7F3D0"/>
-</svg>
diff --git a/apps/web_v1/public/senlinai-icon.svg b/apps/web_v1/public/senlinai-icon.svg
index e88854d..1d0f141 100644
--- a/apps/web_v1/public/senlinai-icon.svg
+++ b/apps/web_v1/public/senlinai-icon.svg
@@ -1,5 +1,4 @@
-<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 128 128" role="img" aria-labelledby="title">
-  <title id="title">森林AI</title>
+<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 128 128">
   <rect x="4" y="4" width="120" height="120" rx="28" fill="#165DFF"/>
   <path d="M64 23C43 23 27 40 27 61c0 13 7 24 17 30h40c10-6 17-17 17-30 0-21-16-38-37-38Z" fill="#F4F8FF"/>
   <path d="M64 99V65M64 76 47 61M64 82l18-16M64 68l12-13" fill="none" stroke="#F4F8FF" stroke-linecap="round" stroke-linejoin="round" stroke-width="10"/>
diff --git a/apps/web_v1/scripts/structure-check.mjs b/apps/web_v1/scripts/structure-check.mjs
index 1a01c8a..b2a844e 100644
--- a/apps/web_v1/scripts/structure-check.mjs
+++ b/apps/web_v1/scripts/structure-check.mjs
@@ -48,6 +48,18 @@ const html = readFileSync('index.html', 'utf8')
 if (!html.includes('<html lang="zh-CN">')) failures.push('index language must be zh-CN')
 if (!html.includes('<title>森林AI</title>')) failures.push('document title must be 森林AI')
 if (!existsSync('public/senlinai-icon.svg')) failures.push('missing public/senlinai-icon.svg')
+if (!html.includes('href="/senlinai-icon.svg"')) failures.push('index must use senlinai-icon.svg as the canonical favicon')
+if (existsSync('public/favicon.svg')) failures.push('legacy public/favicon.svg must be removed; senlinai-icon.svg is the only brand asset')
+if (existsSync('public/senlinai-icon.svg')) {
+  const icon = readFileSync('public/senlinai-icon.svg', 'utf8')
+  if (icon.includes('<text') || icon.includes('<title')) failures.push('brand SVG must not include text or title metadata')
+  if (icon.includes('role=') || icon.includes('aria-labelledby=')) failures.push('brand SVG must not expose presentation ARIA')
+}
+const appStyles = readFileSync('src/App.css', 'utf8')
+if (!appStyles.includes('.brand-icon {')) failures.push('brand-icon must have an explicit base size')
+if (!appStyles.includes('.brand-lockup.large .brand-icon')) failures.push('login brand icon must have an explicit size')
+if (!appStyles.includes('.rail-brand {')) failures.push('rail brand button must have explicit layout')
+if (appStyles.includes('.brand-symbol')) failures.push('legacy brand-symbol styles must be removed')
 for (const file of ['src/pages/login.tsx', 'src/pages/projects/project-topbar.tsx', 'src/pages/projects/project-rail.tsx']) {
   const source = readFileSync(file, 'utf8')
   if (!source.includes('/senlinai-icon.svg')) failures.push(`${file} must use the brand icon`)
diff --git a/apps/web_v1/src/App.css b/apps/web_v1/src/App.css
index bce5986..4862596 100644
--- a/apps/web_v1/src/App.css
+++ b/apps/web_v1/src/App.css
@@ -113,23 +113,17 @@
   gap: 16px;
 }
 
-.brand-symbol {
+.brand-icon {
   width: 32px;
   height: 32px;
-  display: grid;
-  place-items: center;
-  border-radius: 8px;
-  background: var(--senlin-primary);
-  color: white;
-  font-weight: 800;
-  font-size: 18px;
+  display: block;
+  flex: 0 0 32px;
 }
 
-.brand-lockup.large .brand-symbol {
+.brand-lockup.large .brand-icon {
   width: 46px;
   height: 46px;
-  border-radius: 12px;
-  font-size: 24px;
+  flex-basis: 46px;
 }
 
 .brand-name {
@@ -332,6 +326,25 @@
   width: 48px;
 }
 
+.rail-brand {
+  width: 48px;
+  height: 48px;
+  min-width: 48px;
+  display: grid;
+  place-items: center;
+  padding: 0;
+  border: 0;
+  border-radius: 8px;
+  background: transparent;
+  cursor: pointer;
+}
+
+.rail-brand .brand-icon {
+  width: 32px;
+  height: 32px;
+  flex-basis: auto;
+}
+
 .dashboard-button,
 .create-project {
   width: 48px !important;
