fix(css): consistent spacing in threads

also added spacing to navbar (independent of profile-banner)

src/sass/index.scss

@@ -114,7 +114,7 @@ ul {
     display: flex;
     flex-wrap: wrap;
     box-sizing: border-box;
-    padding-top: 50px;
+    padding-top: 55px;
     margin: auto;
     min-height: 100vh;
 }

src/sass/profile/_base.scss

@@ -15,7 +15,7 @@
 }
 
 .profile-banner {
-    margin: 4px 0 4px 0;
+    margin-bottom: 5px;
     background-color: var(--bg_panel);
 
     a {

src/sass/tweet/thread.scss

@@ -10,7 +10,7 @@
 }
 
 .main-thread {
-    margin-bottom: 20px;
+    margin-bottom: 5px;
     background-color: var(--bg_panel);
 }
 
@@ -31,13 +31,13 @@
 
 .reply {
     background-color: var(--bg_panel);
-    margin-bottom: 10px;
+    margin-bottom: 5px;
 }
 
 .thread-line {
     .timeline-item::before,
     &.timeline-item::before {
-        background: var(--accent_dark);
+        background: var(--dark_grey);
         content: '';
         position: relative;
         min-width: 3px;