Improve notification icon and navbar (#25111)v1.21.0-dev

Improvements to the notification icon and `<nav>`:

- Add a opaque color for header hover and use it, allowing the border to
be the right color on hover (sadly, not otherwise possible with CSS, not
even `color-mix`).
- Increase font size by 1px
- Use flexbox for slightly better text centering
- Reduce padding of user and add repo button, add margin on right side
of user menu
- Remove the `following bar` wrapper on navbar

<img width="176" alt="Screenshot 2023-06-07 at 00 07 08"
src="https://github.com/go-gitea/gitea/assets/115237/23cdc3d6-7f63-49df-bec3-f2e75e32a304">
<img width="63" alt="Screenshot 2023-06-07 at 00 07 14"
src="https://github.com/go-gitea/gitea/assets/115237/fae602c2-4467-4d50-b1ec-56317843f9a2">
<img width="84" alt="Screenshot 2023-06-07 at 00 07 36"
src="https://github.com/go-gitea/gitea/assets/115237/c48141b8-0b3c-48cc-846a-3a272524dbdb">
<img width="329" alt="Screenshot 2023-06-07 at 00 25 10"
src="https://github.com/go-gitea/gitea/assets/115237/cda612f1-426e-466b-a351-fc992bfd18fd">
<img width="186" alt="Screenshot 2023-06-07 at 00 35 45"
src="https://github.com/go-gitea/gitea/assets/115237/04484a2e-9bbf-493c-aa26-8e936da008fa">
<img width="797" alt="Screenshot 2023-06-07 at 16 57 40"
src="https://github.com/go-gitea/gitea/assets/115237/e7ccb672-5807-4cb6-b306-b18ae0c7e321">

4 files changed, 45 insertions, 36 deletions

diff --git a/web_src/css/base.css b/web_src/css/base.css
index a35eccb26b..b56e7b68d6 100644
--- a/web_src/css/base.css
+++ b/web_src/css/base.css
@@ -195,8 +195,8 @@
   --color-input-toggle-background: #dedede;
   --color-input-border: #dedede;
   --color-input-border-hover: #cecece;
-  --color-navbar: #f8f8f8;
-  --color-navbar-transparent: #f8f8f800;
+  --color-header-wrapper: #f8f8f8;
+  --color-header-wrapper-transparent: #f8f8f800;
   --color-light: #00000006;
   --color-light-mimic-enabled: rgba(0, 0, 0, calc(6 / 255 * 222 / 255 / var(--opacity-disabled)));
   --color-light-border: #0000001d;
@@ -223,7 +223,8 @@
   --color-reaction-active-bg: var(--color-primary-light-6);
   --color-tooltip-text: #ffffff;
   --color-tooltip-bg: #000000f0;
-  --color-header-bar: #ffffff;
+  --color-nav-bg: #ffffff;
+  --color-nav-hover-bg: #ebebeb;
   --color-label-text: #232323;
   --color-label-bg: #cacaca5b;
   --color-label-hover-bg: #cacacaa0;
@@ -946,44 +947,44 @@ img.ui.avatar,
   }
 }
 
-.following.bar {
-  margin: 0 !important;
-}
-
-.following.bar.light {
-  background: var(--color-header-bar);
+#navbar {
+  display: flex;
+  align-items: center;
+  background: var(--color-nav-bg);
   border-bottom: 1px solid var(--color-secondary);
+  width: 100vw;
+  min-height: 52px;
+  margin: 0 !important;
 }
 
-.following.bar .column .menu {
+#navbar .column .menu {
   margin-top: 0;
 }
 
-.following.bar .fitted .svg {
+#navbar .fitted .svg {
   margin-right: 0;
   vertical-align: middle;
 }
 
-.following.bar .searchbox {
+#navbar .searchbox {
   background-color: var(--color-input-background) !important;
 }
 
-.following.bar .text .svg {
+#navbar .text .svg {
   width: 16px;
   text-align: center;
 }
 
-.following.bar #navbar {
-  width: 100vw;
-  min-height: 52px;
+#navbar a.item:hover {
+  background: var(--color-nav-hover-bg);
 }
 
-.following.bar #navbar .dropdown .avatar {
+#navbar .dropdown .avatar {
   margin-right: 0 !important;
 }
 
 @media (max-width: 767px) {
-  .following.bar #navbar:not(.shown) > *:not(:first-child) {
+  #navbar:not(.shown) > *:not(:first-child) {
     display: none;
   }
 }
@@ -1576,7 +1577,7 @@ img.ui.avatar,
 
 .ui.menu.new-menu {
   margin-bottom: 15px;
-  background: var(--color-navbar);
+  background: var(--color-header-wrapper);
   border-bottom: 1px solid var(--color-secondary) !important;
   overflow: auto;
 }
@@ -1591,7 +1592,7 @@ img.ui.avatar,
 .ui.menu.new-menu::after {
   position: absolute;
   display: block;
-  background: linear-gradient(to right, var(--color-navbar-transparent), var(--color-navbar) 100%);
+  background: linear-gradient(to right, var(--color-header-wrapper-transparent), var(--color-header-wrapper) 100%);
   content: '';
   right: 0;
   height: 39px;
@@ -2126,24 +2127,31 @@ a.ui.basic.label:hover {
   width: 13px;
   height: 13px;
   background: var(--color-primary);
-  border: 2px solid var(--color-header-bar);
+  border: 2px solid var(--color-nav-bg);
   border-radius: 100%;
 }
 
 .notification_count {
+  display: flex;
+  align-items: center;
+  justify-content: center;
   position: absolute;
-  left: 7px;
-  top: -9px;
-  min-width: 1.5em;
-  text-align: center;
+  left: 6px;
+  top: -8px;
+  min-width: 17px;
+  min-height: 17px;
   background: var(--color-primary);
-  border: 2px solid var(--color-header-bar);
-  color: var(--color-header-bar);
-  padding: 2.75px;
-  border-radius: 1em;
-  font-size: 11px;
+  border: 2px solid var(--color-nav-bg);
+  color: var(--color-nav-bg);
+  border-radius: 17px;
+  padding: 0 3.5px;
+  font-size: 12px;
+  line-height: 12px;
   font-weight: var(--font-weight-bold);
-  line-height: .7;
+}
+
+#navbar a.item:hover .notification_count {
+  border-color: var(--color-nav-hover-bg);
 }
 
 .rss-icon {
diff --git a/web_src/css/explore.css b/web_src/css/explore.css
index ee05918e77..f4d1eed960 100644
--- a/web_src/css/explore.css
+++ b/web_src/css/explore.css
@@ -1,6 +1,6 @@
 .explore .navbar {
   margin-bottom: 15px !important;
-  background-color: var(--color-navbar) !important;
+  background-color: var(--color-header-wrapper) !important;
   border-width: 1px !important;
 }
 
diff --git a/web_src/css/repo.css b/web_src/css/repo.css
index 4e300be878..c6655a8fc9 100644
--- a/web_src/css/repo.css
+++ b/web_src/css/repo.css
@@ -132,7 +132,7 @@
 }
 
 .repository .header-wrapper {
-  background-color: var(--color-navbar);
+  background-color: var(--color-header-wrapper);
 }
 
 .repository .header-wrapper .ui.tabs.divider {
diff --git a/web_src/css/themes/theme-arc-green.css b/web_src/css/themes/theme-arc-green.css
index f6321c9ed7..b07a171b52 100644
--- a/web_src/css/themes/theme-arc-green.css
+++ b/web_src/css/themes/theme-arc-green.css
@@ -180,8 +180,8 @@
   --color-input-toggle-background: #454a57;
   --color-input-border: #454a57;
   --color-input-border-hover: #505667;
-  --color-navbar: #2a2e3a;
-  --color-navbar-transparent: #2a2e3a00;
+  --color-header-wrapper: #2a2e3a;
+  --color-header-wrapper-transparent: #2a2e3a00;
   --color-light: #00000028;
   --color-light-mimic-enabled: rgba(0, 0, 0, calc(40 / 255 * 222 / 255 / var(--opacity-disabled)));
   --color-light-border: #ffffff28;
@@ -207,7 +207,8 @@
   --color-reaction-active-bg: var(--color-primary-light-5);
   --color-tooltip-text: #ffffff;
   --color-tooltip-bg: #000000f0;
-  --color-header-bar: #2e323e;
+  --color-nav-bg: #2e323e;
+  --color-nav-hover-bg: #434651;
   --color-label-text: #dfe3ec;
   --color-label-bg: #7c84974b;
   --color-label-hover-bg: #7c8497a0;