fix <button> style affecting buttons across the whole website

now the push-button style is opt-in, in case you need it

content/netcanv.dj

@@ -309,21 +309,21 @@ Here is an interactive visualisation of how the immediate-mode layout system wor
     <div class="controls">
         <p>Stack</p>
         <div class="category">
-            <button name="push-h">Push Horizontal</button>
-            <button name="push-v">Push Vertical</button>
-            <button name="pop">Pop</button>
+            <button class="push" name="push-h">Push Horizontal</button>
+            <button class="push" name="push-v">Push Vertical</button>
+            <button class="push" name="pop">Pop</button>
             <hr>
-            <button name="reset">Reset</button>
+            <button class="push" name="reset">Reset</button>
         </div>
         <p>Rectangle</p>
         <div class="category">
-            <button name="space">Space</button>
-            <button name="pad">Pad</button>
-            <button name="fit">Fit</button>
+            <button class="push" name="space">Space</button>
+            <button class="push" name="pad">Pad</button>
+            <button class="push" name="fit">Fit</button>
         </div>
         <p>Drawing</p>
         <div class="category">
-            <button name="fill">Fill</button>
+            <button class="push" name="fill">Fill</button>
         </div>
     </div>
 

static/css/main.css

@@ -415,9 +415,9 @@ hr {
     margin-bottom: 2em;
 }
 
-/* Buttons */
+/* Push buttons */
 
-button {
+button.push {
     padding: 0.2rem 1.2rem;
 
     border: 1px solid var(--border-2);