From 0f7a48b32381d9703f81674aa66be334a2f5e75e Mon Sep 17 00:00:00 2001
From: Adorian Doran <adorian@esevo.ro>
Date: Mon, 1 Dec 2025 01:55:03 +0200
Subject: [PATCH] style/calendar collection: add basic support for the legacy
 theme

---
 apps/client/src/stylesheets/style.css             | 11 +++++++++++
 apps/client/src/stylesheets/theme-dark.css        |  3 +++
 apps/client/src/stylesheets/theme-light.css       |  3 +++
 .../src/widgets/collections/calendar/index.css    | 15 ++++++++++++---
 4 files changed, 29 insertions(+), 3 deletions(-)

diff --git a/apps/client/src/stylesheets/style.css b/apps/client/src/stylesheets/style.css
index 5db4b1582..847cca27b 100644
--- a/apps/client/src/stylesheets/style.css
+++ b/apps/client/src/stylesheets/style.css
@@ -27,6 +27,9 @@
     --bs-body-bg: var(--main-background-color) !important;    
     --ck-mention-list-max-height: 500px;    
     --tn-modal-max-height: 90vh;
+
+    --tree-item-light-theme-max-color-lightness: 50;
+    --tree-item-dark-theme-min-color-lightness: 75;
 }
 
 body#trilium-app.motion-disabled *,
@@ -2579,4 +2582,12 @@ iframe.print-iframe {
     position: relative;
     flex-grow: 1;
     width: 100%;
+}
+
+/* Calendar collection */
+
+.calendar-view a.fc-timegrid-event,
+.calendar-view a.fc-daygrid-event {
+    /* Workaround: set font weight only if the theme-next is not active */
+    font-weight: var(--root-background, 800);
 }
\ No newline at end of file
diff --git a/apps/client/src/stylesheets/theme-dark.css b/apps/client/src/stylesheets/theme-dark.css
index 0354e3346..690d49ecd 100644
--- a/apps/client/src/stylesheets/theme-dark.css
+++ b/apps/client/src/stylesheets/theme-dark.css
@@ -76,6 +76,9 @@
 
     --mermaid-theme: dark;
     --native-titlebar-background: #00000000;
+
+    --calendar-coll-event-background-saturation: 30%;
+    --calendar-coll-event-background-lightness: 30%;
 }
 
 body ::-webkit-calendar-picker-indicator {
diff --git a/apps/client/src/stylesheets/theme-light.css b/apps/client/src/stylesheets/theme-light.css
index 0208ed97c..0c14a2d92 100644
--- a/apps/client/src/stylesheets/theme-light.css
+++ b/apps/client/src/stylesheets/theme-light.css
@@ -80,6 +80,9 @@ html {
 
     --mermaid-theme: default;
     --native-titlebar-background: #ffffff00;
+
+    --calendar-coll-event-background-lightness: 95%;
+    --calendar-coll-event-background-saturation: 80%;
 }
 
 #left-pane .fancytree-node.tinted {
diff --git a/apps/client/src/widgets/collections/calendar/index.css b/apps/client/src/widgets/collections/calendar/index.css
index 460c4f25a..b364876ef 100644
--- a/apps/client/src/widgets/collections/calendar/index.css
+++ b/apps/client/src/widgets/collections/calendar/index.css
@@ -1,3 +1,12 @@
+:root {
+    /* Default values to be overridden by themes */
+    --calendar-coll-event-background-lightness: 95%;
+    --calendar-coll-event-background-saturation: 80%;
+    --calendar-coll-event-background-color: var(--accented-background-color);
+    --calendar-coll-event-text-color: var(--primary-button-text-color);
+    --calendar-cell-event-hover-filter: none;
+}
+
 .calendar-view {
     --fc-event-border-color: var(--calendar-coll-event-text-color);
     --fc-event-bg-color: var(--calendar-coll-event-background-color);
@@ -115,8 +124,8 @@ body.desktop:not(.zen) .calendar-view .calendar-header {
     color: currentColor;
 }
 
-.fc-timegrid-event.with-hue,
-.fc-daygrid-event:not(.fc-daygrid-dot-event).with-hue {
+.calendar-view .fc-timegrid-event.with-hue,
+.calendar-view .fc-daygrid-event:not(.fc-daygrid-dot-event).with-hue {
     --fc-event-text-color: var(--custom-color);
 
     background: hsl(var(--custom-color-hue),
@@ -124,7 +133,7 @@ body.desktop:not(.zen) .calendar-view .calendar-header {
                     var(--calendar-coll-event-background-lightness)) !important;
 }
 
-.fc-event-time {
+.calendar-view .fc-event-time {
     opacity: .75;
 }