feat(app-content): Revise sidebar selection and content edge styling

Main content now has a subtle left divider and rounded left edge next
to the navigation. Selected nav and list items use a softly tinted
pill instead of a solid primary fill.

Signed-off-by: nfebe <fenn25.fn@gmail.com>

Author: nfebe

src/assets/NcAppNavigationItem.scss

@@ -28,16 +28,42 @@
 		}
 	}
 
-	// When .active class is applied, change color background of link and utils. The
-	// !important prevents the focus state to override the active state.
-	&.active {
+	// !important so :focus-within does not override the active state.
+	// New design (NC34+): glassy tinted bg + inline-start stripe.
+	&:not(.app-navigation-entry--legacy).active {
+		background-color: color-mix(in srgb, var(--color-primary-element) 16%, transparent) !important;
+
+		&:hover {
+			background-color: color-mix(in srgb, var(--color-primary-element) 25%, transparent) !important;
+		}
+
+		&:not(.app-navigation-entry--editing) {
+			.app-navigation-entry-link,
+			.app-navigation-entry-button {
+				color: var(--color-main-text) !important;
+			}
+		}
+
+		&:not(.app-navigation-entry--editing)::before {
+			content: '';
+			position: absolute;
+			inset-block: calc(var(--default-grid-baseline, 4px) * 2);
+			inset-inline-start: 0;
+			width: 3px;
+			background-color: var(--color-primary-element);
+			border-radius: 999px;
+			animation: nc-nav-stripe-in var(--animation-quick, 200ms) ease-out;
+		}
+	}
+
+	// Legacy design (NC < 34): solid primary fill.
+	&.app-navigation-entry--legacy.active {
 		background-color: var(--color-primary-element) !important;
 
 		&:hover {
 			background-color: var(--color-primary-element-hover) !important;
 		}
 
-		// overwrite active text color
 		.app-navigation-entry-link, .app-navigation-entry-button {
 			color: var(--color-primary-element-text) !important;
 		}
@@ -46,6 +72,10 @@
 	&:hover {
 		background-color: var(--color-background-hover);
 	}
+	&:not(.app-navigation-entry--legacy):focus-within,
+	&:not(.app-navigation-entry--legacy):hover {
+		background-color: color-mix(in srgb, var(--color-primary-element) 8%, transparent);
+	}
 	&.active,
 	&:focus-within,
 	&:hover {
@@ -71,7 +101,10 @@
 	.app-navigation-entry__actions:hover :deep(.button-vue) {
 		background-color: var(--color-background-dark) !important;
 	}
-	&.active .app-navigation-entry__actions:hover :deep(.button-vue) {
+	&:not(.app-navigation-entry--legacy).active .app-navigation-entry__actions:hover :deep(.button-vue) {
+		background-color: var(--color-background-dark) !important;
+	}
+	&.app-navigation-entry--legacy.active .app-navigation-entry__actions:hover :deep(.button-vue) {
 		background-color: var(--color-primary-element) !important;
 	}
 
@@ -97,6 +130,7 @@
 		padding: 0;
 		white-space: nowrap;
 		color: var(--color-main-text);
+		font-weight: 500;
 		background-repeat: no-repeat;
 		background-position: $icon-margin center;
 		background-size: $icon-size $icon-size;
@@ -227,3 +261,14 @@
 		}
 	}
 }
+
+@keyframes nc-nav-stripe-in {
+	from {
+		transform: scaleY(0);
+		opacity: 0;
+	}
+	to {
+		transform: scaleY(1);
+		opacity: 1;
+	}
+}

src/components/NcAppNavigation/NcAppNavigation.vue

@@ -145,6 +145,7 @@ import NcAppNavigationList from '../NcAppNavigationList/NcAppNavigationList.vue'
 import NcAppNavigationToggle from './NcAppNavigationToggle.vue'
 import { useIsMobile } from '../../composables/useIsMobile/index.ts'
 import { getTrapStack } from '../../utils/focusTrap.ts'
+import { isLegacy34 } from '../../utils/legacy.ts'
 import { HAS_APP_NAVIGATION_KEY } from '../NcContent/constants.ts'
 
 const props = defineProps<{
@@ -296,7 +297,10 @@ function handleEsc(): void {
 	<div
 		ref="appNavigationContainer"
 		class="app-navigation"
-		:class="{ 'app-navigation--closed': !open }">
+		:class="{
+			'app-navigation--closed': !open,
+			'app-navigation--legacy': isLegacy34,
+		}">
 		<nav
 			id="app-navigation-vue"
 			:aria-hidden="open ? 'false' : 'true'"
@@ -354,9 +358,14 @@ function handleEsc(): void {
 	user-select: none;
 	flex-grow: 0;
 	flex-shrink: 0;
-	background-color: var(--color-main-background-blur, var(--color-main-background));
-	-webkit-backdrop-filter: var(--filter-background-blur, none);
-	backdrop-filter: var(--filter-background-blur, none);
+	// New design (NC34+): transparent so the frosted chrome on NcContent shows through.
+	background-color: transparent;
+
+	&--legacy {
+		background-color: var(--color-main-background-blur, var(--color-main-background));
+		-webkit-backdrop-filter: var(--filter-background-blur, none);
+		backdrop-filter: var(--filter-background-blur, none);
+	}
 
 	&--closed {
 		margin-inline-start: calc(-1 * min($navigation-width, var(--app-navigation-max-width)));

src/components/NcAppNavigationItem/NcAppNavigationIconCollapsible.vue

@@ -12,7 +12,7 @@
 			'icon-collapse--open': open,
 		}"
 		:aria-label="labelButton"
-		:variant="active ? 'tertiary-on-primary' : 'tertiary'"
+		:variant="(active && isLegacy34) ? 'tertiary-on-primary' : 'tertiary'"
 		@click="onClick">
 		<template #icon>
 			<ChevronUp
@@ -29,6 +29,7 @@
 import ChevronDown from 'vue-material-design-icons/ChevronDown.vue'
 import ChevronUp from 'vue-material-design-icons/ChevronUp.vue'
 import { t } from '../../l10n.ts'
+import { isLegacy34 } from '../../utils/legacy.ts'
 import NcButton from '../NcButton/index.ts'
 
 export default {
@@ -40,6 +41,10 @@ export default {
 		ChevronUp,
 	},
 
+	setup() {
+		return { isLegacy34 }
+	},
+
 	props: {
 		/**
 		 * Is the list currently open (or collapsed)

src/components/NcAppNavigationItem/NcAppNavigationItem.vue

@@ -322,6 +322,7 @@ Just set the `pinned` prop.
 				:class="{
 					'app-navigation-entry--editing': editingActive,
 					'app-navigation-entry--deleted': undo,
+					'app-navigation-entry--legacy': isLegacy34,
 					active: (to && isActive) || active,
 				}">
 				<!-- Icon and name -->
@@ -391,7 +392,7 @@ Just set the `pinned` prop.
 						:open="menuOpen"
 						:forceMenu="forceMenu"
 						:defaultIcon="menuIcon"
-						:variant="(to && isActive) || active ? 'tertiary-on-primary' : 'tertiary'"
+						variant="tertiary"
 						@update:open="onMenuToggle">
 						<template #icon>
 							<!-- @slot Slot for the custom menu icon -->
@@ -444,6 +445,7 @@ import NcInputConfirmCancel from './NcInputConfirmCancel.vue'
 import { useIsMobile } from '../../composables/useIsMobile/index.js'
 import { t } from '../../l10n.ts'
 import { createElementId } from '../../utils/createElementId.ts'
+import { isLegacy34 } from '../../utils/legacy.ts'
 import NcActionButton from '../NcActionButton/index.js'
 import NcActions from '../NcActions/index.js'
 import NcLoadingIcon from '../NcLoadingIcon/index.ts'
@@ -663,6 +665,7 @@ export default {
 	setup() {
 		return {
 			isMobile: useIsMobile(),
+			isLegacy34,
 		}
 	},
 

src/components/NcAppNavigationItem/NcInputConfirmCancel.vue

@@ -12,7 +12,7 @@
 </docs>
 
 <template>
-	<div class="app-navigation-input-confirm">
+	<div class="app-navigation-input-confirm" :class="{ 'app-navigation-input-confirm--legacy': isLegacy34 }">
 		<form
 			@submit.prevent="confirm"
 			@keydown.esc.exact.stop.prevent="cancel"
@@ -51,6 +51,7 @@
 import IconArrowRight from 'vue-material-design-icons/ArrowRight.vue'
 import IconClose from 'vue-material-design-icons/Close.vue'
 import { t } from '../../l10n.ts'
+import { isLegacy34 } from '../../utils/legacy.ts'
 import NcButton from '../NcButton/index.js'
 
 export default {
@@ -62,6 +63,10 @@ export default {
 		NcButton,
 	},
 
+	setup() {
+		return { isLegacy34 }
+	},
+
 	props: {
 		/**
 		 * If this element is used on a primary element set to true for primary styling.
@@ -156,5 +161,25 @@ $input-margin: 5px;
 			border-color: var(--color-primary-element);
 		}
 	}
+
+	// New design (NC34+): square confirm/cancel buttons with consistent gaps.
+	&:not(&--legacy) {
+		form {
+			align-items: center;
+			gap: $input-margin;
+			padding-inline-end: $input-margin;
+		}
+
+		.app-navigation-input-confirm__input {
+			margin-inline-end: 0 !important;
+		}
+
+		:deep(.button-vue) {
+			width: $input-height !important;
+			min-width: $input-height !important;
+			height: $input-height !important;
+			flex: 0 0 $input-height;
+		}
+	}
 }
 </style>

src/components/NcContent/NcContent.vue

@@ -71,6 +71,7 @@ import NcButton from '../NcButton/NcButton.vue'
 import NcIconSvgWrapper from '../NcIconSvgWrapper/NcIconSvgWrapper.vue'
 import { useIsMobile } from '../../composables/useIsMobile/index.js'
 import { t } from '../../l10n.ts'
+import { isLegacy34 } from '../../utils/legacy.ts'
 import { CONTENT_SELECTOR_KEY, HAS_APP_NAVIGATION_KEY } from './constants.ts'
 import contentSvg from './content-selected.svg?raw'
 import navigationSvg from './navigation-selected.svg?raw'
@@ -145,7 +146,10 @@ function setAppNavigation(value: boolean): void {
 </script>
 
 <template>
-	<div id="content-vue" class="content" :class="`app-${appName.toLowerCase()}`">
+	<div
+		id="content-vue"
+		class="content"
+		:class="[`app-${appName.toLowerCase()}`, { 'content--legacy': isLegacy34 }]">
 		<Teleport to="#skip-actions">
 			<div class="vue-skip-actions__container">
 				<div class="vue-skip-actions__headline">
@@ -190,6 +194,15 @@ function setAppNavigation(value: boolean): void {
 	padding: var(--body-container-margin)!important;
 	backdrop-filter: brightness(50%);
 }
+
+// New design (NC34+): divider only when an open navigation is present.
+@media only screen and (min-width: $breakpoint-mobile) {
+	.content:not(.content--legacy) .app-navigation:not(.app-navigation--closed):not(.app-navigation--close) ~ .app-content {
+		border-inline-start: 1px solid var(--color-border);
+		border-start-start-radius: var(--body-container-radius);
+		border-end-start-radius: var(--body-container-radius);
+	}
+}
 </style>
 
 <style lang="scss" scoped>
@@ -236,6 +249,14 @@ function setAppNavigation(value: boolean): void {
 	overflow: hidden;
 	padding: 0;
 
+	// New design (NC34+): wrapper carries the frosted chrome so nav and
+	// AppContent rounded-edge cutouts share one surface.
+	&:not(&--legacy) {
+		background-color: var(--color-main-background-blur, var(--color-main-background));
+		backdrop-filter: var(--filter-background-blur, none);
+		-webkit-backdrop-filter: var(--filter-background-blur, none);
+	}
+
 	&:not(.with-sidebar--full) {
 		position: fixed;
 	}