change the className='wrapper' in to className='container'

src/container/FlashMessage.jsx

   render() {
     return(
       <div className='flashmessage'>
-        <div className='flashmessage__wrapper card'>
-          <div className='flashmessage__header' />
+        <div className='flashmessage__container card'>
+          <div className='flashmessage__container__header' />
 
           <div className='card-body nopadding'>
 
-            <div className='flashmessage__close'>
+            <div className='flashmessage__container__close'>
               <i className='fa fa-times' />
             </div>
 
-            <div className='flashmessage__content'>
-              <div className='flashmessage__content__icon'>
+            <div className='flashmessage__container__content'>
+              <div className='flashmessage__container__content__icon'>
                 <i className='fa fa-times-circle' />
               </div>
 
-              <div className='flashmessage__content__text'>
-                <div className='flashmessage__content__text__title'>
+              <div className='flashmessage__container__content__text'>
+                <div className='flashmessage__container__content__text__title'>
                   Sorry !
                 </div>
-                <div className='flashmessage__content__text__paragraph'>
+                <div className='flashmessage__container__content__text__paragraph'>
                   Reprehenderit reprehenderit veniam dolore velit dolor velit in occaecat dolor veniam nisi officia velit consequat amet cupidatat.
                   Reprehenderit reprehenderit veniam dolore velit dolor velit in occaecat dolor veniam nisi officia velit consequat amet cupidatat.
                 </div>

src/container/Tracim.jsx

 import Login from './Login.jsx'
 import Dashboard from './Dashboard.jsx'
 import AccountPage from './AccountPage.jsx'
+import FlashMessage from './FlashMessage.jsx'
 import WorkspaceContent from './WorkspaceContent.jsx'
 import {
   Route,

src/css/FlashMessage.styl

   justify-content center
   width 100%
   z-index 3
-  &__wrapper
+  &__container
     margin-top 120px
     border 0
     border-radius 10px
     width 800px
     background lightGrey
     box-shadow shadow-all
-  &__header
-    border-top-right-radius 10px
-    border-top-left-radius 10px
-    width 100%
-    height 8px
-    background-color calendar
-  &__close
-    display flex
-    justify-content flex-end
-    margin 5px
-    cursor pointer
-  &__content
-    display flex
-    align-items center
-    margin 10px 0 35px 0
-    &__icon
-      padding 0 30px
-      font-size 60px
-      color calendar
-    &__text
-      &__title
-        margin-bottom 10px
-        font-size 20px
-        font-weight 600
+    &__header
+      border-top-right-radius 10px
+      border-top-left-radius 10px
+      width 100%
+      height 8px
+      background-color calendar
+    &__close
+      display flex
+      justify-content flex-end
+      margin 5px
+      cursor pointer
+    &__content
+      display flex
+      align-items center
+      margin 10px 0 35px 0
+      &__icon
+        padding 0 30px
+        font-size 60px
         color calendar
-      &__paragraph
-        padding-right 20px
-        font-weight 500
+      &__text
+        &__title
+          margin-bottom 10px
+          font-size 20px
+          font-weight 600
+          color calendar
+        &__paragraph
+          padding-right 20px
+          font-weight 500