Unify button CSS

assets/style.css

@@ -82,7 +82,7 @@ header {
     color: #060;
 }
 
-.edit-btn {
+.btn {
     background: none;
     border: none;
     color: #ffb300;
@@ -90,34 +90,17 @@ header {
     cursor: pointer;
     padding: 0;
     text-decoration: none;
+    display: inline-block;
     white-space: nowrap;
+    text-shadow: inherit;
 }
-.edit-btn::before {
+.btn::before {
     content: "[";
 }
-.edit-btn::after {
+.btn::after {
     content: "]";
 }
-.edit-btn:hover {
-    color: #ffd54f;
-}
-
-.new-btn {
-    background: none;
-    border: none;
-    color: #ffb300;
-    font: inherit;
-    cursor: pointer;
-    padding: 0;
-    white-space: nowrap;
-}
-.new-btn::before {
-    content: "[";
-}
-.new-btn::after {
-    content: "]";
-}
-.new-btn:hover {
+.btn:hover {
     color: #ffd54f;
 }
 
@@ -268,22 +251,15 @@ main {
 }
 
 .btn-tool {
-    background: none;
-    border: none;
     color: #0f0;
-    font: inherit;
     font-size: 0.85rem;
-    cursor: pointer;
     padding: 0 0.15rem;
     text-shadow: 0 0 4px #0a0;
-    white-space: nowrap;
 }
 .btn-tool::before {
-    content: "[";
     color: #060;
 }
 .btn-tool::after {
-    content: "]";
     color: #060;
 }
 .btn-tool:hover {
@@ -326,45 +302,6 @@ textarea:focus {
     box-shadow: 0 0 5px #0a0;
 }
 
-.btn-save {
-    background: none;
-    border: none;
-    color: #ffb300;
-    font: inherit;
-    cursor: pointer;
-    text-shadow: inherit;
-    padding: 0;
-}
-.btn-save::before {
-    content: "[";
-}
-.btn-save::after {
-    content: "]";
-}
-.btn-save:hover {
-    color: #ffd54f;
-}
-
-.btn-cancel {
-    background: none;
-    border: none;
-    color: #ffb300;
-    font: inherit;
-    text-shadow: inherit;
-    cursor: pointer;
-    padding: 0;
-    text-decoration: none;
-    display: inline-block;
-}
-.btn-cancel::before {
-    content: "[";
-}
-.btn-cancel::after {
-    content: "]";
-}
-.btn-cancel:hover {
-    color: #ffb300;
-}
 
 /* === Diary views === */
 .diary-section {