diff --git a/src/agenda/reservation-list/style.ts b/src/agenda/reservation-list/style.ts
index b0b6505f85..366faafe16 100644
--- a/src/agenda/reservation-list/style.ts
+++ b/src/agenda/reservation-list/style.ts
@@ -37,6 +37,6 @@ export default function styleConstructor(theme: Theme = {}) {
     indicator: {
       marginTop: 80
     },
-    ...(theme['stylesheet.agenda.list'] || {})
+    ...(theme.stylesheet?.agenda?.list ?? {})
   });
 }
diff --git a/src/agenda/style.ts b/src/agenda/style.ts
index 60176e3975..321a26493b 100644
--- a/src/agenda/style.ts
+++ b/src/agenda/style.ts
@@ -52,6 +52,6 @@ export default function styleConstructor(theme: Theme = {}) {
       width: '100%',
       alignSelf: 'center'
     },
-    ...(theme['stylesheet.agenda.main'] || {})
+    ...(theme.stylesheet?.agenda?.main ?? {})
   });
 }
diff --git a/src/calendar-list/style.ts b/src/calendar-list/style.ts
index 7bba2a5e9d..29233ce3e6 100644
--- a/src/calendar-list/style.ts
+++ b/src/calendar-list/style.ts
@@ -33,6 +33,6 @@ export default function getStyle(theme: Theme = {}) {
       backgroundColor: appStyle.calendarBackground,
       paddingHorizontal: 15
     },
-    ...(theme['stylesheet.calendar-list.main'] || {})
+    ...(theme.stylesheet?.['calendar-list']?.main ?? {})
   });
 }
diff --git a/src/calendar/day/basic/style.ts b/src/calendar/day/basic/style.ts
index f0350e4355..d8bc2ebb48 100644
--- a/src/calendar/day/basic/style.ts
+++ b/src/calendar/day/basic/style.ts
@@ -45,7 +45,6 @@ export default function styleConstructor(theme: Theme = {}) {
     inactiveText: {
       color: appStyle.textInactiveColor
     },
-    
-    ...(theme['stylesheet.day.basic'] || {})
+    ...(theme.stylesheet?.day?.basic ?? {})
   });
 }
diff --git a/src/calendar/day/dot/style.ts b/src/calendar/day/dot/style.ts
index 057c0b841e..eeafeddc85 100644
--- a/src/calendar/day/dot/style.ts
+++ b/src/calendar/day/dot/style.ts
@@ -30,6 +30,6 @@ export default function styleConstructor(theme: Theme = {}) {
     todayDot: {
       backgroundColor: appStyle.todayDotColor
     },
-    ...(theme['stylesheet.dot'] || {})
+    ...(theme.stylesheet?.dot ?? {})
   });
 }
diff --git a/src/calendar/day/marking/style.ts b/src/calendar/day/marking/style.ts
index 1feba83dd0..7f30cc6005 100644
--- a/src/calendar/day/marking/style.ts
+++ b/src/calendar/day/marking/style.ts
@@ -26,6 +26,6 @@ export default function styleConstructor(theme: Theme = {}) {
       borderBottomRightRadius: 2,
       marginRight: 4
     },
-    ...(theme['stylesheet.marking'] || {})
+    ...(theme.stylesheet?.marking ?? {})
   });
 }
diff --git a/src/calendar/day/period/style.ts b/src/calendar/day/period/style.ts
index ec68c762fa..31bcc4ecba 100644
--- a/src/calendar/day/period/style.ts
+++ b/src/calendar/day/period/style.ts
@@ -60,7 +60,6 @@ export default function styleConstructor(theme: Theme = {}) {
     inactiveText: {
       color: appStyle.textInactiveColor
     },
-    
-    ...(theme['stylesheet.day.period'] || {})
+    ...(theme.stylesheet?.day?.period ?? {})
   });
 }
diff --git a/src/calendar/header/style.ts b/src/calendar/header/style.ts
index cf6d36c23c..5078e5b657 100644
--- a/src/calendar/header/style.ts
+++ b/src/calendar/header/style.ts
@@ -68,6 +68,6 @@ export default function (theme: Theme = {}) {
     disabledDayHeader: {
       color: appStyle.textSectionTitleDisabledColor
     },
-    ...(theme['stylesheet.calendar.header'] || {})
+    ...(theme.stylesheet?.calendar?.header ?? {})
   });
 }
diff --git a/src/calendar/style.ts b/src/calendar/style.ts
index 69ffb04567..11cc16970b 100644
--- a/src/calendar/style.ts
+++ b/src/calendar/style.ts
@@ -25,6 +25,6 @@ export default function getStyle(theme: Theme = {}) {
       flexDirection: 'row',
       justifyContent: 'space-around'
     },
-    ...(theme['stylesheet.calendar.main'] || {})
+    ...(theme.stylesheet?.calendar?.main ?? {})
   });
 }
diff --git a/src/expandableCalendar/style.ts b/src/expandableCalendar/style.ts
index ff8b3cb582..0794999261 100644
--- a/src/expandableCalendar/style.ts
+++ b/src/expandableCalendar/style.ts
@@ -171,6 +171,6 @@ export default function styleConstructor(theme: Theme = {}) {
       marginLeft: appStyle.todayButtonPosition === 'right' ? 7 : undefined,
       marginRight: appStyle.todayButtonPosition === 'right' ? undefined : 7
     },
-    ...(theme?.stylesheet?.expandable?.main || {})
+    ...(theme.stylesheet?.expandable?.main ?? {})
   });
 }