MD Settings: Fix alignment issues after adding left/right padding to md-select.

ui/webui/resources/html/md_select_css.html

Index: ui/webui/resources/html/md_select_css.html
diff --git a/ui/webui/resources/html/md_select_css.html b/ui/webui/resources/html/md_select_css.html
index 59f97c7e58b24232771cff478505b0e1aada921b..0c483beffdd2ad6b7a9946b6138db8d86d210800 100644
--- a/ui/webui/resources/html/md_select_css.html
+++ b/ui/webui/resources/html/md_select_css.html
@@ -12,6 +12,7 @@
       .md-select {
         --md-arrow-width: 0.9em;
         -webkit-appearance: none;
+        -webkit-margin-end: calc(-1 * var(--md-side-padding));
         /* Ensure that the text does not overlap with the down arrow. */
         -webkit-padding-end: calc(var(--md-side-padding) +
             var(--md-arrow-width) * 1.8);
@@ -28,7 +29,7 @@
         outline: none;
         padding-bottom: 4px;
         padding-top: 3px;
-        width: var(--md-select-width, 200px);
+        width: calc(var(--md-select-width, 200px) + 2 * var(--md-side-padding));
       }
 
       /* Mirroring paper-dropdown-menu disabled style. */
@@ -45,9 +46,12 @@
 
       /* Persistent underline */
       .md-select-underline {
+        -webkit-margin-end: 0;
+        -webkit-margin-start: var(--md-side-padding);
         border-top: 1px solid var(--paper-grey-300);
         display: block;
-        margin: 0 var(--md-side-padding);
+        margin-bottom: 0;
+        margin-top: 0;
       }
 
       /* Focus underline */