diff --git a/src/build-output.test.ts b/src/build-output.test.ts
index f93562e1..eb2fe6b6 100644
--- a/src/build-output.test.ts
+++ b/src/build-output.test.ts
@@ -183,6 +183,7 @@ describe("Forgejo 15 native integration", () => {
     "repo/home_sidebar_top.tmpl",
     "repo/view_content.tmpl",
     "repo/view_list.tmpl",
+    "user/heatmap.tmpl",
   ];
 
   const unsupportedSelectorFamilies = [
@@ -461,6 +462,13 @@ describe("Forgejo 15 native integration", () => {
       expect(fs.existsSync(path.join(ROOT_DIR, "templates", template)), `missing template: ${template}`).toBe(true);
     }
   });
+
+  it("keeps the native dated fallback for zero-contribution heatmap tooltips", () => {
+    const heatmapTemplate = fs.readFileSync(path.join(ROOT_DIR, "templates", "user", "heatmap.tmpl"), "utf-8");
+
+    expect(heatmapTemplate).toContain("data-heatmap-data");
+    expect(heatmapTemplate).not.toContain("data-locale-contributions-zero");
+  });
 });
 
 describe("auto 主题 CSS 内容验证", () => {
diff --git a/styles/components/heatmap.ts b/styles/components/heatmap.ts
index 0f99512e..4526f955 100644
--- a/styles/components/heatmap.ts
+++ b/styles/components/heatmap.ts
@@ -53,7 +53,8 @@ const heatmap = css`
       outline: 0.5px solid ${themeVars.github.contribution.default.borderColor.num0};
       outline-offset: -0.5px;
       &:hover {
-        outline: 0.5px solid ${themeVars.color.text.self} !important;
+        outline: 1px solid ${themeVars.color.tooltip.text} !important;
+        outline-offset: -1px;
       }
       &[style="fill: var(--color-secondary-alpha-60);"] {
         fill: ${themeVars.github.contribution.default.bgColor.num0} !important;
@@ -80,6 +81,20 @@ const heatmap = css`
       }
     }
   }
+  /* Forgejo's heatmap tooltip is unthemed; scope the GitHub treatment to the heatmap page. */
+  body:has(#user-heatmap) .tippy-box:not([data-theme]) {
+    background-color: ${themeVars.color.tooltip.bg};
+    color: ${themeVars.color.tooltip.text};
+    border: 0;
+    font-size: 12px;
+    line-height: 19.5px;
+    .tippy-content {
+      font-size: 12px;
+      font-weight: 400;
+      line-height: 19.5px;
+      padding: 4px 8px;
+    }
+  }
 `;
 
 // 动态
diff --git a/templates/user/heatmap.tmpl b/templates/user/heatmap.tmpl
new file mode 100644
index 00000000..0a34ee87
--- /dev/null
+++ b/templates/user/heatmap.tmpl
@@ -0,0 +1,12 @@
+{{if .HeatmapData}}
+	<div id="user-heatmap" class="is-loading"
+		data-heatmap-data="{{JsonUtils.EncodeToString .HeatmapData}}"
+		data-locale-total-contributions="{{ctx.Locale.Tr "heatmap.number_of_contributions_in_the_last_12_months" (ctx.Locale.PrettyNumber .HeatmapTotalContributions)}}"
+		data-locale-contributions-format="{{ctx.Locale.Tr "heatmap.contributions_format"}}"
+		data-locale-contributions-one="{{ctx.Locale.Tr "heatmap.contributions_one"}}"
+		data-locale-contributions-few="{{ctx.Locale.Tr "heatmap.contributions_few"}}"
+		data-locale-more="{{ctx.Locale.Tr "heatmap.more"}}"
+		data-locale-less="{{ctx.Locale.Tr "heatmap.less"}}"
+		></div>
+	<div class="divider"></div>
+{{end}}