harmonize gap rules, fix CSS for Grid block

Author: MarieComet

src/scss/03-base/_variables-css.scss

@@ -36,6 +36,7 @@
     /*
      * Spacing
      */
+    --spacing--block-default: 16px;
     --spacing--block-1: 16px;
     --spacing--block-2: 32px;
     --spacing--block-3: 48px;

src/scss/06-blocks/_gutenberg.scss

@@ -102,11 +102,16 @@
         margin-bottom: var(--spacing--block-1);
     }
 
+    :where(.is-layout-flex),
+    :where(.is-layout-grid) {
+        gap: get-gutter-width();
+    }
+
     // ----
     // Alignements verticaux
     // ----
     > *,
-    [class*="inner-container"] > * {
+    [class*="inner-container"]:not(.is-layout-grid) > * {
         margin-top: var(--spacing--block-1);
         margin-bottom: var(--spacing--block-1);
 

src/scss/06-blocks/core/_columns.scss

@@ -1,6 +1,5 @@
 .wp-block-columns {
     @include block-vertical-spacing();
-    gap: get-gutter-width() !important;
 
     .wp-block-column {
         &.has-background {

src/scss/06-blocks/core/_gallery.scss

@@ -1,3 +1,3 @@
-// .wp-block-gallery {
-//     ...
-// }
+.wp-block-gallery {
+    --wp--style--gallery-gap-default: #{get-gutter-width()} !important;
+}

src/scss/06-blocks/core/_group.scss

@@ -1,7 +1,9 @@
 .wp-block-group {
     $el: &;
 
-    display: flow-root;
+    &:not(.is-layout-grid) {
+        display: flow-root;
+    }
 
     &--no-inner-margin {
         #{$el}__inner-container {
@@ -21,7 +23,9 @@
 
 @include editor-only {
     .wp-block-group {
-        display: flow-root;
+        &:not(.is-layout-grid) {
+            display: flow-root;
+        }
 
         .wp-block-group.has-background > .block-editor-block-list__layout > [data-align="full"] {
             width: 100%;