scikit-learn · thomasjpfan · Dec 14, 2025 · Dec 4, 2025 · Dec 5, 2025 · Dec 9, 2025
diff --git a/doc/whats_new/upcoming_changes/sklearn.utils/32887.fix.rst b/doc/whats_new/upcoming_changes/sklearn.utils/32887.fix.rst
@@ -0,0 +1,6 @@
+- The parameter table in the HTML representation of all scikit-learn
+  estimators inheritiging from :class:`base.BaseEstimator`, displays
+  each parameter documentation as a tooltip. The last tooltip of a
+  parameter in the last table of any HTML representation was partially hidden.
+  This issue has been fixed.
+  By :user:`Dea María Léon <DeaMariaLeon>`
diff --git a/sklearn/utils/_repr_html/params.css b/sklearn/utils/_repr_html/params.css
@@ -83,6 +83,14 @@ a.param-doc-link:visited {
     padding: .5em;
 }
 
+@supports(anchor-name: --doc-link) {
+    a.param-doc-link,
+    a.param-doc-link:link,
+    a.param-doc-link:visited {
+    anchor-name: --doc-link;
+    }
+}
+
 /* "hack" to make the entire area of the cell containing the link clickable */
 a.param-doc-link::before {
     position: absolute;
@@ -109,6 +117,14 @@ a.param-doc-link::before {
     border: thin solid var(--sklearn-color-unfitted-level-3);
 }
 
+@supports(position-area: center right) {
+    .param-doc-description {
+    position-area: center right;
+    position: fixed;
+    margin-left: 0;
+    }
+}
+
 /* Fitted state for parameter tooltips */
 .fitted .param-doc-description {
     /* fitted */

diff --git a/sklearn/utils/_repr_html/params.py b/sklearn/utils/_repr_html/params.py
@@ -89,9 +89,12 @@ def _params_html_repr(params):
 
     PARAM_AVAILABLE_DOC_LINK_TEMPLATE = """
         <a class="param-doc-link"
+            style="anchor-name: --doc-link-{param_name};"
             rel="noreferrer" target="_blank" href="{link}">
             {param_name}
-            <span class="param-doc-description">{param_description}</span>
+            <span class="param-doc-description"
+            style="position-anchor: --doc-link-{param_name};">
+            {param_description}</span>
         </a>
     """
     estimator_class_docs = inspect.getdoc(params.estimator_class)

diff --git a/sklearn/utils/_repr_html/tests/test_params.py b/sklearn/utils/_repr_html/tests/test_params.py
@@ -108,10 +108,13 @@ class MockEstimator:
     html_param_a = (
         r'<td class="param">'
         r'\s*<a class="param-doc-link"'
+        r'\s*style="anchor-name: --doc-link-a;"'
         r'\s*rel="noreferrer" target="_blank"'
         r'\shref="mock_module\.MockEstimator\.html#:~:text=a,-int">'
         r"\s*a"
-        r'\s*<span class="param-doc-description">a: int<br><br>'
+        r'\s*<span class="param-doc-description"'
+        r'\s*style="position-anchor: --doc-link-a;">\s*a:'
+        r"\sint<br><br>"
         r"Description of a\.</span>"
         r"\s*</a>"
         r"\s*</td>"
@@ -120,10 +123,13 @@ class MockEstimator:
     html_param_b = (
         r'<td class="param">'
         r'.*<a class="param-doc-link"'
+        r'\s*style="anchor-name: --doc-link-b;"'
         r'\s*rel="noreferrer" target="_blank"'
         r'\shref="mock_module\.MockEstimator\.html#:~:text=b,-str">'
         r"\s*b"
-        r'\s*<span class="param-doc-description">b: str<br><br></span>'
+        r'\s*<span class="param-doc-description"'
+        r'\s*style="position-anchor: --doc-link-b;">\s*b:'
+        r"\sstr<br><br></span>"
         r"\s*</a>"
         r"\s*</td>"
     )