tadd file size limit message

public/locales/send.en-US.ftl

@@ -5,6 +5,7 @@ uploadPageExplainer = Send files through a safe, private, and encrypted link tha
 
 uploadPageLearnMore = Learn more
 uploadPageDropMessage = Drop your files here to start uploading
+uploadPageSizeMessage = For the most reliable operation, it’s best to keep your file under 1GB
 uploadPageBrowseButton = Select a file on your computer
   .title = {uploadPageBrowseButtonTitle}
 
@@ -82,4 +83,4 @@ footerLinkLegal = Legal
 footerLinkAbout = About Test Pilot
 footerLinkPrivacy = Privacy
 footerLinkTerms = Terms
-footerLinkCookies = Cookies
+footerLinkCookies = Cookies

public/main.css

@@ -87,7 +87,7 @@ a {
 #upload-text {
   font-size: 22px;
   color: #737373;
-  margin: 20px 0 30px;
+  margin: 20px 0 10px;
   font-family: 'SF Pro Display', sans-serif;
 }
 
@@ -108,6 +108,12 @@ input[type="file"] {
   display: none;
 }
 
+#file-size-msg {
+  font-size: 12px;
+  color: #737373;
+  margin-bottom: 22px;
+}
+
 /**   file-list   **/
 th {
   font-size: 16px;
@@ -330,6 +336,10 @@ tbody {
   text-align: center;
 }
 
+#upload-error[hidden], #unsupported-browser[hidden] {
+  display: none;
+}
+
 #upload-error-img {
   margin-bottom: 90px;
   margin-top: 5px;
@@ -439,6 +449,10 @@ tbody {
   text-align: center;
 }
 
+#download-progress[hidden] {
+  display: none;
+}
+
 #download-img {
   width: 283px;
   height: 196px;