feat: move all css to includes dir

src/includes/css/utilities/flex.css

@@ -0,0 +1,36 @@
+.flex {
+  display: flex;
+}
+
+.flex-col {
+  display: flex;
+  flex-direction: column;
+}
+
+.items-center {
+  align-items: center;
+}
+
+.items-end {
+  align-items: flex-end;
+}
+
+.justify-center {
+  justify-content: center;
+}
+
+.justify-between {
+  justify-content: space-between;
+}
+
+.flex-wrap {
+  flex-wrap: wrap;
+}
+
+.flex-nowrap {
+  flex-wrap: nowrap;
+}
+
+.flex-1 {
+  flex: 1;
+}