From 8329624ccab1ce3b48302a353dc9254d788ad420 Mon Sep 17 00:00:00 2001
From: Jouni Koivuviita <jouni@vaadin.com>
Date: Tue, 7 Oct 2025 12:10:02 +0300
Subject: [PATCH] feat: aura tabs theme

---
 dev/aura.html                         |   9 ++
 packages/aura/aura.css                |   1 +
 packages/aura/src/color.css           |   3 +-
 packages/aura/src/components/tabs.css | 125 ++++++++++++++++++++++++++
 packages/aura/src/surface.css         |   1 +
 5 files changed, 138 insertions(+), 1 deletion(-)
 create mode 100644 packages/aura/src/components/tabs.css

diff --git a/dev/aura.html b/dev/aura.html
index 5d20e593ee..7d271a9740 100644
--- a/dev/aura.html
+++ b/dev/aura.html
@@ -43,6 +43,7 @@
       import '@vaadin/select';
       import '@vaadin/scroller';
       import '@vaadin/side-nav';
+      import '@vaadin/tabs';
       import '@vaadin/text-field';
       import '@vaadin/vertical-layout';
       import { html, render } from 'lit';
@@ -597,6 +598,14 @@ <h1>Components</h1>
                   </vaadin-checkbox>
                 </div>
 
+                <div class="aura-surface component wide">
+                  <vaadin-tabs>
+                    <vaadin-tab>Details<span theme="badge accent">2</span></vaadin-tab>
+                    <vaadin-tab>Preferences</vaadin-tab>
+                    <vaadin-tab>Settings</vaadin-tab>
+                  </vaadin-tabs>
+                </div>
+
                 <div class="aura-surface component wide">
                   <vaadin-date-time-picker style="width: 20em" value="2025-09-09T12:00"></vaadin-date-time-picker>
                 </div>
diff --git a/packages/aura/aura.css b/packages/aura/aura.css
index 60436afaf2..3d90d41d07 100644
--- a/packages/aura/aura.css
+++ b/packages/aura/aura.css
@@ -30,6 +30,7 @@
 @import './src/components/rich-text-editor.css';
 @import './src/components/select.css';
 @import './src/components/side-nav.css';
+@import './src/components/tabs.css';
 @import './src/components/upload.css';
 
 :where(:root, :host) {
diff --git a/packages/aura/src/color.css b/packages/aura/src/color.css
index 152161e32b..322d56003d 100644
--- a/packages/aura/src/color.css
+++ b/packages/aura/src/color.css
@@ -89,7 +89,8 @@ vaadin-menu-bar-button,
 vaadin-menu-bar-item,
 vaadin-checkbox::part(checkbox),
 vaadin-radio-button::part(radio),
-vaadin-side-nav-item::part(content) {
+vaadin-side-nav-item::part(content),
+vaadin-tab {
   --aura-accent-contrast-light: oklch(
     from var(--aura-accent-light) clamp(0, (0.62 - l) * 1000, 1) 0 0 / clamp(0.8, (0.62 - l) * 1000, 1)
   );
diff --git a/packages/aura/src/components/tabs.css b/packages/aura/src/components/tabs.css
new file mode 100644
index 0000000000..ffff10fe71
--- /dev/null
+++ b/packages/aura/src/components/tabs.css
@@ -0,0 +1,125 @@
+:where(:root, :host) {
+  --vaadin-tab-font-weight: var(--aura-font-weight-medium);
+  --vaadin-tabs-gap: 2px;
+}
+
+vaadin-tabs {
+  background: var(--vaadin-background-container);
+  border-radius: calc(var(--vaadin-radius-m) + 3px);
+  padding: 3px;
+  contain: paint;
+}
+
+vaadin-tabs:not([theme~='accent']) {
+  --aura-accent-light: var(--aura-text-light);
+  --aura-accent-dark: var(--aura-text-dark);
+}
+
+vaadin-tabs::part(tabs) {
+  padding: 3px;
+  margin: -3px;
+  --_mask-fade-start: 0.5lh;
+  --_mask-fade-size: 2lh;
+  mask-image: linear-gradient(
+    var(--_mask-dir, to right),
+    var(--_mask-start, black) var(--_mask-fade-start),
+    black var(--_mask-fade-size),
+    black calc(100% - var(--_mask-fade-size)),
+    var(--_mask-end, black) calc(100% - var(--_mask-fade-start))
+  );
+}
+
+vaadin-tabs[dir='rtl']::part(tabs) {
+  --_mask-dir: to left;
+}
+
+vaadin-tabs[orientation='vertical']::part(tabs) {
+  --_mask-dir: to bottom;
+  --_mask-fade-start: 0px;
+  --_mask-fade-size: 0.5lh;
+}
+
+vaadin-tabs[overflow~='start'] {
+  --_mask-start: transparent;
+}
+
+vaadin-tabs[overflow~='end'] {
+  --_mask-end: transparent;
+}
+
+vaadin-tabs::part(back-button),
+vaadin-tabs::part(forward-button) {
+  background: var(--aura-surface-solid) padding-box;
+  border: 1px solid var(--vaadin-border-color);
+  border-radius: var(--vaadin-radius-m);
+  padding: var(--vaadin-padding-xs);
+  height: auto;
+  align-self: center;
+  box-shadow: 0 1px 4px -1px var(--aura-shadow-color);
+  transition: opacity 120ms;
+}
+
+vaadin-tabs::part(back-button) {
+  inset-inline-start: 5px;
+}
+
+vaadin-tabs::part(forward-button) {
+  inset-inline-end: 5px;
+}
+
+vaadin-tab {
+  transition:
+    color 120ms,
+    border-color 120ms,
+    background-color 120ms;
+  --aura-surface-level: 8;
+  --aura-surface-opacity: 0.7;
+  border: 1px solid transparent;
+}
+
+vaadin-tab:not([disabled], [selected]):hover {
+  --vaadin-tab-color: var(--vaadin-text-color);
+}
+
+vaadin-tab[selected] {
+  --_accent: light-dark(
+    oklch(from var(--aura-accent-light) calc(l + 0.2) c h / min(0.3, c / 2)),
+    oklch(from var(--aura-accent-dark) calc(l - 0.2) c h / min(0.3, c / 2))
+  );
+  --_accent-border: light-dark(
+    oklch(from var(--aura-accent-light) l calc(c / 2) h / calc(min(0.15, 0.05 + c / 2) + 0.1 * var(--aura-contrast))),
+    oklch(from var(--aura-accent-dark) l calc(c / 2) h / calc(min(0.15, 0.05 + c / 2) + 0.1 * var(--aura-contrast)))
+  );
+  --vaadin-tab-background: linear-gradient(var(--_accent), var(--_accent)) var(--aura-surface) padding-box;
+  --vaadin-tab-color: var(--aura-accent-text);
+  border-color: var(--_accent-border);
+  box-shadow: 0 1px 4px -1px var(--aura-shadow-color);
+}
+
+/* Filled variant */
+
+vaadin-tabs[theme~='filled'] vaadin-tab[selected] {
+  --vaadin-tab-background: var(--aura-accent-color) border-box;
+  --vaadin-tab-color: var(--aura-accent-contrast);
+  outline-offset: 1px;
+}
+
+/* Badges and other content that uses the palette inside a filled nav item */
+vaadin-tabs[theme~='filled'] vaadin-tab[selected] > :not([slot='tooltip']) {
+  --vaadin-text-color: var(--vaadin-tab-color);
+  --vaadin-text-color-secondary: var(--vaadin-tab-color);
+  --aura-accent-color: var(--vaadin-tab-color);
+  --aura-accent-text: var(--vaadin-tab-color);
+  --aura-red: var(--vaadin-tab-color);
+  --aura-red-text: var(--vaadin-tab-color);
+  --aura-orange: var(--vaadin-tab-color);
+  --aura-orange-text: var(--vaadin-tab-color);
+  --aura-yellow: var(--vaadin-tab-color);
+  --aura-yellow-text: var(--vaadin-tab-color);
+  --aura-green: var(--vaadin-tab-color);
+  --aura-green-text: var(--vaadin-tab-color);
+  --aura-blue: var(--vaadin-tab-color);
+  --aura-blue-text: var(--vaadin-tab-color);
+  --aura-purple: var(--vaadin-tab-color);
+  --aura-purple-text: var(--vaadin-tab-color);
+}
diff --git a/packages/aura/src/surface.css b/packages/aura/src/surface.css
index ebf2fb028f..896500de89 100644
--- a/packages/aura/src/surface.css
+++ b/packages/aura/src/surface.css
@@ -19,6 +19,7 @@ vaadin-message-input,
 vaadin-radio-button::part(radio),
 vaadin-rich-text-editor,
 vaadin-side-nav-item::part(content),
+vaadin-tab,
 vaadin-upload,
 vaadin-upload-file,
 ::part(input-field),