diff --git a/browse/css/base.css b/browse/css/base.css
index 17a96fd..65ec2b4 100644
--- a/browse/css/base.css
+++ b/browse/css/base.css
@@ -52,7 +52,7 @@ body {
     margin: 0.4rem 0;
 }
 
-.hidden { display: none !important; }
+/* .hidden lives in shared/base.css; no per-tool override needed. */
 
 /* Status bar — shows transient errors/info */
 .status-bar {
diff --git a/form/css/form.css b/form/css/form.css
index 9fda7b0..deb4f8e 100644
--- a/form/css/form.css
+++ b/form/css/form.css
@@ -1,5 +1,8 @@
 /* form/ — ZDDC generic form renderer.
-   Pulls theme tokens from shared/base.css; only adds form-specific layout. */
+   Form-specific layout only; theme tokens (--primary, --bg, --text,
+   --border, --bg-secondary, --text-muted, --font-mono, --radius) come
+   from shared/base.css. Button styles (.btn, .btn-primary,
+   .btn-secondary, .btn-sm) likewise inherit from shared. */
 
 .form-main {
     max-width: 800px;
@@ -10,20 +13,20 @@
 .form-status {
     padding: 0.75rem 1rem;
     margin-bottom: 1rem;
-    border-radius: 4px;
-    border: 1px solid var(--color-border);
+    border-radius: var(--radius);
+    border: 1px solid var(--border);
 }
 
 .form-status.is-error {
-    background: var(--color-bg-alt);
-    border-color: #c43;
-    color: #c43;
+    background: var(--bg-secondary);
+    border-color: var(--danger);
+    color: var(--danger);
 }
 
 .form-status.is-success {
-    background: var(--color-bg-alt);
-    border-color: #283;
-    color: #283;
+    background: var(--bg-secondary);
+    border-color: var(--success);
+    color: var(--success);
 }
 
 .form-root {
@@ -44,24 +47,24 @@
 }
 
 .form-field__label .required-mark {
-    color: #c43;
+    color: var(--danger);
     margin-left: 0.15rem;
 }
 
 .form-field__description {
     font-size: 0.85rem;
-    color: var(--color-text-muted, #666);
+    color: var(--text-muted);
 }
 
 .form-field__error {
     font-size: 0.85rem;
-    color: #c43;
+    color: var(--danger);
     margin-top: 0.15rem;
 }
 
 .form-field__help {
     font-size: 0.8rem;
-    color: var(--color-text-muted, #666);
+    color: var(--text-muted);
     font-style: italic;
 }
 
@@ -69,10 +72,10 @@
 .form-field__textarea,
 .form-field__select {
     padding: 0.5rem 0.65rem;
-    border: 1px solid var(--color-border);
-    border-radius: 4px;
-    background: var(--color-bg, #fff);
-    color: var(--color-text, #111);
+    border: 1px solid var(--border);
+    border-radius: var(--radius);
+    background: var(--bg);
+    color: var(--text);
     font: inherit;
     width: 100%;
     box-sizing: border-box;
@@ -86,14 +89,14 @@
 .form-field__input:focus,
 .form-field__textarea:focus,
 .form-field__select:focus {
-    outline: 2px solid var(--color-primary, #1e3a5f);
+    outline: 2px solid var(--primary);
     outline-offset: -1px;
 }
 
 .form-field--invalid .form-field__input,
 .form-field--invalid .form-field__textarea,
 .form-field--invalid .form-field__select {
-    border-color: #c43;
+    border-color: var(--danger);
 }
 
 .form-field__radio-group,
@@ -113,8 +116,8 @@
 }
 
 .form-fieldset {
-    border: 1px solid var(--color-border);
-    border-radius: 4px;
+    border: 1px solid var(--border);
+    border-radius: var(--radius);
     padding: 0.75rem 1rem 1rem;
     display: flex;
     flex-direction: column;
@@ -136,10 +139,10 @@
     display: flex;
     gap: 0.5rem;
     align-items: flex-start;
-    border: 1px solid var(--color-border);
-    border-radius: 4px;
+    border: 1px solid var(--border);
+    border-radius: var(--radius);
     padding: 0.5rem;
-    background: var(--color-bg-alt, #f6f6f8);
+    background: var(--bg-secondary);
 }
 
 .form-array__row-body {
@@ -165,41 +168,8 @@
     gap: 0.5rem;
 }
 
-.btn {
-    padding: 0.5rem 1rem;
-    border-radius: 4px;
-    border: 1px solid var(--color-border);
-    background: var(--color-bg, #fff);
-    color: var(--color-text, #111);
-    cursor: pointer;
-    font: inherit;
-}
-
-.btn:hover {
-    background: var(--color-bg-alt, #f6f6f8);
-}
-
-.btn-primary {
-    background: var(--color-primary, #1e3a5f);
-    color: #fff;
-    border-color: var(--color-primary, #1e3a5f);
-}
-
-.btn-primary:hover {
-    filter: brightness(1.1);
-}
-
-.btn-small {
-    padding: 0.2rem 0.5rem;
-    font-size: 0.85rem;
-}
-
-.btn[disabled] {
-    opacity: 0.5;
-    cursor: not-allowed;
-}
-
-/* Standalone welcome — shown when form.html is opened directly (no server-injected #form-context). */
+/* Standalone welcome — shown when form.html is opened directly (no
+   server-injected #form-context). */
 .form-welcome {
     max-width: 36rem;
     margin: 2rem auto;
diff --git a/form/js/array.js b/form/js/array.js
index 2737e1e..7074bce 100644
--- a/form/js/array.js
+++ b/form/js/array.js
@@ -54,7 +54,7 @@
                 const actions = u.h('div', { className: 'form-array__row-actions' });
                 const removeBtn = u.h('button', {
                     type: 'button',
-                    className: 'btn btn-small',
+                    className: 'btn btn-sm btn-secondary',
                     title: 'Remove this row',
                     onClick: function () { removeRow(rowEl); }
                 }, '×');
@@ -85,7 +85,7 @@
         if (addable) {
             const addBtn = u.h('button', {
                 type: 'button',
-                className: 'btn btn-small form-array__add',
+                className: 'btn btn-sm btn-secondary form-array__add',
                 onClick: function () { addRow(undefined); }
             }, '+ Add');
             wrap.appendChild(addBtn);
diff --git a/tests/form-safety.spec.js b/tests/form-safety.spec.js
index aee3b1a..50d4acc 100644
--- a/tests/form-safety.spec.js
+++ b/tests/form-safety.spec.js
@@ -108,8 +108,9 @@ test.describe('form/ — safety check-in renderer', () => {
         await page.locator('.form-array__add').click();
         await expect(page.locator('.form-array__row')).toHaveCount(2);
 
-        // Remove the first row.
-        await page.locator('.form-array__row').first().locator('button.btn-small').click();
+        // Remove the first row. Button now uses shared .btn-sm
+        // instead of the legacy form-local .btn-small class.
+        await page.locator('.form-array__row').first().locator('button.btn-sm').click();
         await expect(page.locator('.form-array__row')).toHaveCount(1);
     });