[css-forms] Use :is() for UA sheet.

This is more compact, and reveals that <input type=reset> was forgotten
in a couple places.

Author: emilio

css-forms-1/Overview.bs

@@ -238,7 +238,7 @@ spec:css-forms-1; type:value; for:/; text:::placeholder
         </pre>
 
         See [[#date-time-pseudos]]
-        
+
         </td>
       </tr>
       <tr>
@@ -366,7 +366,7 @@ spec:css-forms-1; type:value; for:/; text:::placeholder
       the portion that allows the user to adjust the progress of the control.
 
       NOTE: It is typically natively rendered as a circle in most user agents.
-    
+
     <dt><dfn>::slider-track</dfn>
     <dd>
       The ''::slider-track'' pseudo-element represents the portion containing
@@ -479,7 +479,7 @@ spec:css-forms-1; type:value; for:/; text:::placeholder
     <dd>
       The ''::step-control'' pseudo-element represents
       the portion of a number input that contains the up and down buttons.
-    
+
     <dt><dfn>::step-up</dfn>
     <dd>
       The ''::step-up'' pseudo-element represents
@@ -543,7 +543,7 @@ spec:css-forms-1; type:value; for:/; text:::placeholder
     <dd>
       The ''::field-component'' pseudo-element represents
       the portions of the control that contain the date/time component values.
-    
+
     <dt><dfn>::field-separator</dfn>
     <dd>
       The ''::field-separator'' pseudo-element represents
@@ -701,7 +701,7 @@ spec:css-forms-1; type:value; for:/; text:::placeholder
 
   <pre class=propdef>
   Name: slider-orientation
-  Value: auto | left-to-right | right-to-left | top-to-bottom | bottom-to-top 
+  Value: auto | left-to-right | right-to-left | top-to-bottom | bottom-to-top
   Initial: auto
   Inherited: no
   Percentages: n/a
@@ -803,7 +803,7 @@ spec:css-forms-1; type:value; for:/; text:::placeholder
   </div>
 
 <h2 class="no-num non-normative" id="basic-appearance-stylesheet">Appendix A: Basic Appearance User Agent Stylesheet</h2>
-  
+
   ISSUE: Move to HTML.
 
   ISSUE: This section needs refining with implementation.
@@ -968,10 +968,7 @@ Selects are only button-like when they're a [drop-down box](https://html.spec.wh
 button,
 ::file-selector-button,
 select,
-input[type="color"],
-input[type="button"],
-input[type="reset"],
-input[type="submit"] {
+input:is([type="color"], [type="button"], [type="reset"], [type="submit"]) {
   border: 1px solid currentColor;
   background-color: transparent;
   color: inherit;
@@ -1009,27 +1006,21 @@ input[type="submit"] {
 
 button:enabled:hover,
 select:enabled:hover,
-input[type="color"]:enabled:hover,
-input[type="button"]:enabled:hover,
-input[type="submit"]:enabled:hover,
+input:is([type="color"], [type="button"], [type="reset"], [type="submit"]):enabled:hover,
 input[type="file"]:enabled::file-selector-button:hover {
   background-color: color-mix(currentColor 10%, transparent);
 }
 
 button:enabled:active,
 select:enabled:active,
-input[type="color"]:enabled:active,
-input[type="button"]:enabled:active,
-input[type="submit"]:enabled:active,
+input:is([type="color"], [type="button"], [type="reset"], [type="submit"]):enabled:active,
 input[type="file"]:enabled::file-selector-button:active {
   background-color: color-mix(currentColor 20%, transparent);
 }
 
 button:disabled,
 select:disabled,
-input[type="color"]:disabled,
-input[type="button"]:disabled,
-input[type="submit"]:disabled,
+input:is([type="color"], [type="button"], [type="reset"], [type="submit"]):disabled,
 input[type="file"]:disabled::file-selector-button {
   color: color-mix(currentColor 50%, transparent);
 }