diff --git a/assets/sass/_theme/_configuration.sass b/assets/sass/_theme/_configuration.sass
index c60e3d5ac79d00517ab313aaa3d80e0e89f1dd3d..7b908ff77fa040e5715b0576f295551ed64da8f4 100644
--- a/assets/sass/_theme/_configuration.sass
+++ b/assets/sass/_theme/_configuration.sass
@@ -113,6 +113,10 @@ $grid-breakpoints: (xs: 0, sm: 576px, md: 768px, lg: 992px, xl: 1200px, xxl: 140
 $block-call-to-action-background: $main-background-color !default
 $block-call-to-action-color: $main-color !default
 
+// Block definitions
+$definition-border-color: $main-border-color !default
+$definition-border-color-hovered: darken($definition-border-color, 2) !default
+
 // Block pages
 $block-pages-card-background: lighten($main-background-color, 1) !default
 $block-pages-card-page-background: white !default
diff --git a/assets/sass/_theme/blocks/definitions.sass b/assets/sass/_theme/blocks/definitions.sass
index 167850451414cd82ce2aa8623c1c45747c192b46..d13824778e717a7e64ceaf2e1109252242e26ab2 100644
--- a/assets/sass/_theme/blocks/definitions.sass
+++ b/assets/sass/_theme/blocks/definitions.sass
@@ -2,7 +2,7 @@
     details
         &:not([open]):hover
             &::after
-                border-bottom-color: $main-border-color
+                border-bottom-color: $definition-border-color-hovered
             summary::after
                 transform: translateY(5px)
         summary, p
@@ -10,7 +10,7 @@
             // line-height: px2rem(30)
         &::after
             content: ''
-            border-bottom: 1px solid rgba($main-border-color, .1)
+            border-bottom: 1px solid $definition-border-color
             display: block
             transition: border-color 0.5s