Make fileheader sticky in diffs (#14616)

* Make fileheader sticky #12552

* Remove sticky filenames when width is 480px or less

On mobile phone sticky filename is hidden due to the combination
of many possible widths and lengths.

* Fix text color for .markdown-info

* Fix visual of sticky diff box on 480px or less

- Hide arrow for select buttons.
- Fix changes, additions and deletions.
With flexbox they look very broken.
This commit hides some words to, so the result is:
"123 changed files  987 additions  456 deletions"
- center text in buttons

Co-authored-by: zeripath <art27@cantab.net>

1 files changed, 50 insertions, 0 deletions

diff --git a/web_src/less/_repository.less b/web_src/less/_repository.less
index 57f101abb9..88a1a38bb6 100644
--- a/web_src/less/_repository.less
+++ b/web_src/less/_repository.less
@@ -1453,6 +1453,10 @@
       align-items: flex-start;
     }
 
+    @media (max-width: 480px) {
+      flex-wrap: wrap;
+    }
+
     &.sticky {
       position: sticky;
       top: 0;
@@ -1473,6 +1477,17 @@
       margin-right: .25rem;
     }
 
+    .diff-detail-stats {
+      @media (max-width: 480px) {
+        font-size: 0;
+        line-height: 1.6rem;
+
+        strong {
+          font-size: 1rem;
+        }
+      }
+    }
+
     .diff-detail-actions > * {
       margin-right: 0;
     }
@@ -1481,6 +1496,21 @@
       margin-left: .25rem;
     }
 
+    .diff-detail-actions {
+      @media (max-width: 480px) {
+        padding-top: .25rem;
+
+        .ui.button {
+          padding-left: .5rem;
+          padding-right: .5rem;
+          display: flex;
+          flex-wrap: wrap;
+          justify-content: center;
+          text-align: center;
+        }
+      }
+    }
+
     span.status {
       display: inline-block;
       width: 12px;
@@ -2996,6 +3026,26 @@ td.blob-excerpt {
   margin-left: .5rem !important;
 }
 
+.ui.attached.header.diff-file-header {
+  &.sticky-2nd-row {
+    position: sticky;
+    top: 46px;
+    z-index: 7;
+
+    @media @mediaMd {
+      top: 77px;
+    }
+
+    @media @mediaSm {
+      top: 77px;
+    }
+
+    @media (max-width: 480px) {
+      position: static;
+    }
+  }
+}
+
 .diff-stats-bar {
   display: inline-block;
   background-color: var(--color-red);