diff --git a/frontend/src/assets/scss/custom/gradido-custom/_color.scss b/frontend/src/assets/scss/custom/gradido-custom/_color.scss
index b8bf23fe2..20fcbefd6 100644
--- a/frontend/src/assets/scss/custom/gradido-custom/_color.scss
+++ b/frontend/src/assets/scss/custom/gradido-custom/_color.scss
@@ -68,7 +68,7 @@ $warning: $orange !default;
 $danger: $red !default;
 $light: $gray-500 !default;
 $dark: $gray-900 !default;
-$darker: color.adjust($gray-900, -15%) !default;
+$darker: color.adjust($gray-900, $lightness: -15%) !default;
 $facebook: #3b5999 !default;
 $twitter: #1da1f2 !default;
 $google-plus: #dd4b39 !default;
diff --git a/frontend/src/assets/scss/custom/gradido-custom/_datepicker.scss b/frontend/src/assets/scss/custom/gradido-custom/_datepicker.scss
index e29e1efec..e745c22c5 100644
--- a/frontend/src/assets/scss/custom/gradido-custom/_datepicker.scss
+++ b/frontend/src/assets/scss/custom/gradido-custom/_datepicker.scss
@@ -4,7 +4,7 @@
 $datepicker-border-radius: $card-border-radius !default;
 $datepicker-dropdown-padding: 20px 22px !default;
 $datepicker-cell-transition: $transition-base !default;
-$datepicker-cell-hover-background: color.adjust($gray-400, 55%);
+$datepicker-cell-hover-background: color.adjust($gray-400, $lightness: 55%);
 $datepicker-cell-border-radius: 50% !default;
 $datepicker-cell-width: 36px !default;
 $datepicker-cell-height: 36px !default;
@@ -15,9 +15,9 @@ $datepicker-active-color: $white !default;
 $datepicker-active-background: theme-color("primary") !default;
 $datepicker-active-box-shadow: none !default;
 $datepicker-range-background: theme-color("primary") !default;
-$datepicker-range-cell-focused-background: color.adjust($datepicker-range-background, -5%);
+$datepicker-range-cell-focused-background: color.adjust($datepicker-range-background, $lightness: -5%);
 $datepicker-range-color: $white !default;
 $datepicker-range-highlighted-bg: $gray-200 !default;
-$datepicker-dropdown-border: color.adjust($gray-400, 40%);
+$datepicker-dropdown-border: color.adjust($gray-400, $lightness: 40%);
 $datepicker-dropdown-bg: $white !default;
 $datepicker-highlighted-bg: $datepicker-active-background !default;
diff --git a/frontend/src/assets/scss/custom/gradido-custom/_form-validation.scss b/frontend/src/assets/scss/custom/gradido-custom/_form-validation.scss
index 3db6ea8be..0d9243e08 100644
--- a/frontend/src/assets/scss/custom/gradido-custom/_form-validation.scss
+++ b/frontend/src/assets/scss/custom/gradido-custom/_form-validation.scss
@@ -1,7 +1,7 @@
 // Form validation
 @use "sass:color";
 
-$form-feedback-valid-bg: color.adjust($success, 15%) !default;
+$form-feedback-valid-bg: color.adjust($success, $lightness: 15%) !default;
 $form-feedback-valid-color: theme-color("success") !default;
-$form-feedback-invalid-bg: color.adjust($warning, 15%) !default;
+$form-feedback-invalid-bg: color.adjust($warning, $lightness: 15%) !default;
 $form-feedback-invalid-color: theme-color("warning") !default;
diff --git a/frontend/src/assets/scss/custom/gradido-custom/_input.scss b/frontend/src/assets/scss/custom/gradido-custom/_input.scss
index 63475134f..12ecf12e5 100644
--- a/frontend/src/assets/scss/custom/gradido-custom/_input.scss
+++ b/frontend/src/assets/scss/custom/gradido-custom/_input.scss
@@ -17,7 +17,7 @@ $input-border-radius-sm: $border-radius-sm !default;
 $input-bg: $white !default;
 $input-disabled-bg: $gray-200 !default;
 $input-muted-bg: #f7fafe !default;
-$input-focus-muted-bg: color.adjust($input-muted-bg, 1%) !default;
+$input-focus-muted-bg: color.adjust($input-muted-bg, $lightness: 1%) !default;
 $input-alternative-box-shadow: 0 1px 3px rgb(50 50 93 / 15%), 0 1px 0 rgb(0 0 0 / 2%) !default;
 $input-focus-alternative-box-shadow: 0 4px 6px rgb(50 50 93 / 11%),0 1px 3px rgb(0 0 0 / 8%) !default;
 $input-color: $gray-600 !default;
diff --git a/frontend/src/assets/scss/custom/gradido-custom/_links.scss b/frontend/src/assets/scss/custom/gradido-custom/_links.scss
index f46994c94..bf06c470f 100644
--- a/frontend/src/assets/scss/custom/gradido-custom/_links.scss
+++ b/frontend/src/assets/scss/custom/gradido-custom/_links.scss
@@ -3,5 +3,5 @@
 
 $link-color: $primary !default;
 $link-decoration: none !default;
-$link-hover-color: color.adjust($link-color, -15%) !default;
+$link-hover-color: color.adjust($link-color, $lightness: -15%) !default;
 $link-hover-decoration: none !default;
diff --git a/frontend/src/assets/scss/custom/gradido-custom/_navs.scss b/frontend/src/assets/scss/custom/gradido-custom/_navs.scss
index 257044362..106c58c4a 100644
--- a/frontend/src/assets/scss/custom/gradido-custom/_navs.scss
+++ b/frontend/src/assets/scss/custom/gradido-custom/_navs.scss
@@ -14,7 +14,7 @@ $nav-pills-border-width: 1px !default;
 $nav-pills-border-color: theme-color("primary") !default;
 $nav-pills-border-radius: $border-radius !default;
 $nav-pills-link-color: theme-color("primary") !default;
-$nav-pills-link-hover-color: color.adjust(theme-color("primary"), -5%) !default;
+$nav-pills-link-hover-color: color.adjust(theme-color("primary"), $lightness: -5%) !default;
 $nav-pills-link-active-color: color-yiq(theme-color("primary")) !default;
 $nav-pills-link-active-bg: theme-color("primary") !default;
 $nav-pills-box-shadow: $btn-box-shadow !default;
diff --git a/frontend/src/assets/scss/custom/gradido-custom/_tables.scss b/frontend/src/assets/scss/custom/gradido-custom/_tables.scss
index 148190e19..7648d9cc3 100644
--- a/frontend/src/assets/scss/custom/gradido-custom/_tables.scss
+++ b/frontend/src/assets/scss/custom/gradido-custom/_tables.scss
@@ -20,7 +20,7 @@ $table-body-font-size: 0.8125rem !default;
 $table-dark-bg: theme-color("default") !default;
 $table-dark-accent-bg: rgba($white, 0.05) !default;
 $table-dark-hover-bg: rgba($white, 0.075) !default;
-$table-dark-border-color: color.adjust(theme-color("default"), 7%) !default;
+$table-dark-border-color: color.adjust(theme-color("default"), $lightness: 7%) !default;
 $table-dark-color: $body-bg !default;
-$table-dark-head-bg: color.adjust(theme-color("default"), 4%) !default;
-$table-dark-head-color: color.adjust(theme-color("default"), 35%) !default;
+$table-dark-head-bg: color.adjust(theme-color("default"), $lightness: 4%) !default;
+$table-dark-head-color: color.adjust(theme-color("default"), $lightness: 35%) !default;