diff --git a/package-lock.json b/package-lock.json
index 6cb90908..a481c98a 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -23,6 +23,7 @@
                 "@vue/eslint-config-typescript": "^14.3.0",
                 "@vueuse/core": "^12.8.2",
                 "@vueuse/integrations": "^12.5.0",
+                "chroma-js": "3.1.2",
                 "class-variance-authority": "^0.7.1",
                 "clsx": "^2.1.1",
                 "dayjs": "^1.11.11",
@@ -44,6 +45,7 @@
                 "@playwright/test": "^1.41.1",
                 "@tailwindcss/forms": "^0.5.9",
                 "@tailwindcss/typography": "^0.5.15",
+                "@types/chroma-js": "2.4.5",
                 "@types/node": "^22.10.10",
                 "@vitejs/plugin-vue": "^5.2.1",
                 "@vue/tsconfig": "^0.5.1",
@@ -1896,6 +1898,13 @@
                 "vue": "^2.7.0 || ^3.0.0"
             }
         },
+        "node_modules/@types/chroma-js": {
+            "version": "2.4.5",
+            "resolved": "https://registry.npmjs.org/@types/chroma-js/-/chroma-js-2.4.5.tgz",
+            "integrity": "sha512-6ISjhzJViaPCy2q2e6PgK+8HcHQDQ0V2LDiKmYAh+jJlLqDa6HbwDh0wOevHY0kHHUx0iZwjSRbVD47WOUx5EQ==",
+            "dev": true,
+            "license": "MIT"
+        },
         "node_modules/@types/estree": {
             "version": "1.0.7",
             "resolved": "https://registry.npmjs.org/@types/estree/-/estree-1.0.7.tgz",
@@ -2931,6 +2940,12 @@
                 "node": ">= 6"
             }
         },
+        "node_modules/chroma-js": {
+            "version": "3.1.2",
+            "resolved": "https://registry.npmjs.org/chroma-js/-/chroma-js-3.1.2.tgz",
+            "integrity": "sha512-IJnETTalXbsLx1eKEgx19d5L6SRM7cH4vINw/99p/M11HCuXGRWL+6YmCm7FWFGIo6dtWuQoQi1dc5yQ7ESIHg==",
+            "license": "(BSD-3-Clause AND Apache-2.0)"
+        },
         "node_modules/class-variance-authority": {
             "version": "0.7.1",
             "resolved": "https://registry.npmjs.org/class-variance-authority/-/class-variance-authority-0.7.1.tgz",
diff --git a/package.json b/package.json
index 61d58a51..f133c166 100644
--- a/package.json
+++ b/package.json
@@ -19,6 +19,7 @@
         "@playwright/test": "^1.41.1",
         "@tailwindcss/forms": "^0.5.9",
         "@tailwindcss/typography": "^0.5.15",
+        "@types/chroma-js": "2.4.5",
         "@types/node": "^22.10.10",
         "@vitejs/plugin-vue": "^5.2.1",
         "@vue/tsconfig": "^0.5.1",
@@ -55,6 +56,7 @@
         "@vue/eslint-config-typescript": "^14.3.0",
         "@vueuse/core": "^12.8.2",
         "@vueuse/integrations": "^12.5.0",
+        "chroma-js": "3.1.2",
         "class-variance-authority": "^0.7.1",
         "clsx": "^2.1.1",
         "dayjs": "^1.11.11",
diff --git a/resources/js/packages/ui/src/FullCalendar/TimeEntryCalendar.vue b/resources/js/packages/ui/src/FullCalendar/TimeEntryCalendar.vue
index 3995b3d8..6959d32e 100644
--- a/resources/js/packages/ui/src/FullCalendar/TimeEntryCalendar.vue
+++ b/resources/js/packages/ui/src/FullCalendar/TimeEntryCalendar.vue
@@ -5,6 +5,8 @@ import timeGridPlugin from '@fullcalendar/timegrid';
 import interactionPlugin from '@fullcalendar/interaction';
 import type { DatesSetArg, EventClickArg, EventDropArg, EventChangeArg } from '@fullcalendar/core';
 import { computed, ref, watch, inject, type ComputedRef } from 'vue';
+import chroma from 'chroma-js';
+import { useCssVariable } from '@/utils/useCssVariable';
 import { getDayJsInstance, getLocalizedDayJs } from '../utils/time';
 import { getUserTimezone, getWeekStart } from '../utils/settings';
 import { LoadingSpinner, TimeEntryCreateModal, TimeEntryEditModal } from '..';
@@ -94,8 +96,12 @@ const getSlotLabelFormat = () => {
     }
 };
 
-// Map API entries to FullCalendar events
+const cssBackground = useCssVariable('--color-bg-background');
+
 const events = computed(() => {
+    const themeBackground = (() => {
+        return cssBackground.value?.trim();
+    })();
     return props.timeEntries
         ?.filter((timeEntry) => timeEntry.end !== null)
         ?.map((timeEntry) => {
@@ -109,14 +115,18 @@ const events = computed(() => {
 
             const title = timeEntry.description || 'No description';
 
+            const baseColor = project?.color || '#6B7280';
+            const backgroundColor = chroma.mix(baseColor, themeBackground, 0.65, 'lab').hex();
+            const borderColor = chroma.mix(baseColor, themeBackground, 0.5, 'lab').hex();
+
             return {
                 id: timeEntry.id,
                 start: getLocalizedDayJs(timeEntry.start).format(),
                 end: getLocalizedDayJs(timeEntry.end!).format(),
                 title,
-                backgroundColor: project?.color || '#6B7280',
-                borderColor: project?.color || '#6B7280',
-                textColor: '#FFFFFF',
+                backgroundColor,
+                borderColor,
+                textColor: 'var(--foreground)',
                 extendedProps: {
                     timeEntry,
                     project,
@@ -249,6 +259,8 @@ watch(showCreateTimeEntryModal, (value) => {
     if (!value) {
         newEventStart.value = null;
         newEventEnd.value = null;
+        // Ensure FullCalendar clears the selection mirror when modal closes
+        calendarRef.value?.getApi().unselect();
         emit('refresh');
     }
 });
@@ -427,7 +439,6 @@ watch(showEditTimeEntryModal, (value) => {
 }
 
 .fullcalendar :deep(.fc-event) {
-    border: 1px solid !important;
     border-radius: var(--radius);
     padding: 0.45rem 0.25rem;
     font-size: 0.75rem;