unify header

assets/css/partials/_site-header.scss

@@ -1,17 +1,12 @@
-@keyframes add-border {
-  from {
-    border-bottom-color: transparent;
-  }
-  to {
-    border-bottom: var(--grey-800);
-  }
-}
-
 #site-header {
 
   z-index: 900;
   --gap: 3ch;
 
+  position: fixed;
+  top: 0;
+  left: 0;
+
   width: 100vw;
   height: var(--header-h);
   background-color: var(--color-bg);
@@ -20,6 +15,8 @@
   .site-header__inner{
     width: 100%;
     height: 100%;
+    border-bottom: 1px solid var(--color-bg);
+    transition: border-color ease-in .5s;
 
     display: flex;
     align-items: center;
@@ -107,36 +104,10 @@
 }
 
 
+
 #site-header.is-visible{
-  position: fixed;
-  top: 0;
-
   .site-header__inner{
-    border-bottom: var(--border-light);
-
-    #nav-highlight li:not(.soutenir){
-      display: none;
-    }
-    #site-title {
-      @media #{$small-up}{
-      flex-grow: 0;
-      width: calc((100vw - var(--max-w-content))/2 - var(--padding-body)*2);
-      } 
-      @media #{$medium}{
-        width: calc(var(--banner-medium) - var(--padding-body));
-      } 
-    } 
-    
-    .header__title-page{
-      @media #{$small-up}{
-       display: block;
-      }
-      flex-grow: 2;
-    }
-  }
-
-  & ~ main{
-    margin-top: var(--header-h);
+    border-color: var(--grey-800);
   }
 }