grid-colorをtransition

src/app.css

@@ -6,6 +6,10 @@
     syntax: "<color>";
     inherits: true;
 }
+@property --grid-color {
+    syntax: "<color>";
+    inherits: true;
+}
 
 /* theme color */
 body, body.light {

src/routes/(DefaultStyle)/+layout.svelte

@@ -77,7 +77,7 @@
         & header {
             background-color: var(--theme-color);
             height: 100%;
-            transition: height .4s, transform .4s background-color 1s;
+            transition: height .4s, transform .4s, background-color 1s;
             &.hide {
                 height: 40px;
                 @media(width<1000px) {

src/routes/(DefaultStyle)/[slug]/grid.svelte

@@ -34,6 +34,7 @@
         flex-direction: column;
         position: relative;
         background-color: var(--grid-color);
+        transition: background-color 1s;
         &:hover {
             img {
                 transform: scale(1.03);

src/routes/(DefaultStyle)/footer.svelte

@@ -33,6 +33,7 @@
         font-family: "Source Code Pro", "Monaco", "Consolas", monospace;
         height: fit-content;
         background-color: var(--theme-color);
+        transition: background-color 1s;
         color: white;
 
         & a {

src/routes/(DefaultStyle)/post/[slug]/+page.svelte

@@ -120,6 +120,7 @@
 		}
 		& #side>* {
 			background-color: var(--grid-color);
+			transition: background-color 1s;
 			border-radius: 8px;
 			box-shadow: 0 0 6px #1111;
 			overflow: hidden;