Settings UI: fix main pane layout for Safety check bottom spacing (#36328)

* Update settings_ui.ts

* [settings-section]: Add bottom margin

---------

Co-authored-by: Jay Harris <jay.harris@outlook.co.nz>

browser/resources/settings/br/settings_section.ts

@@ -15,6 +15,7 @@ RegisterStyleOverride(
       }
 
       #header .title {
+        margin-top: calc(var(--cr-section-vertical-margin) - var(--leo-spacing-xl)) !important;
         font-size: var(--leo-typography-heading-h4-font-size) !important;
         font-weight: 600 !important;
         padding-top: var(--leo-spacing-xl) !important;
@@ -22,6 +23,11 @@ RegisterStyleOverride(
         margin-bottom: 0 !important;
         letter-spacing: 0 !important;
       }
+
+      #card {
+        margin-bottom: var(--leo-spacing-xl);
+      }
+
       :host(:not(.expanded)) #card {
         box-shadow: var(--leo-effect-elevation-01) !important;
         background-color: var(--leo-color-container-background) !important;

browser/resources/settings/br/settings_ui.ts

@@ -82,9 +82,7 @@ RegisterStyleOverride(
       }
       #main {
         margin: 0 var(--leo-spacing-m) var(--leo-spacing-m) 0;
-        height: calc(100% - 40px);
         background: var(--leo-color-page-background);
-        padding-bottom: var(--leo-spacing-2xl);
         border-radius: var(--leo-radius-xl) var(--leo-radius-m) var(--leo-radius-m) var(--leo-radius-xl);
         overflow: auto;
       }