[Hard Reject] How to improve my first admin theme

Hello, friends.
I upload my first HTML-template (Superial admin) for testing and received “hard reject”.
I would be very grateful if you help me understand where I make mistakes.
Demo: http://91.234.35.26/superial-admin/
Here is a letter I received from Themeforest:

Unfortunately your submission Superial - Responsive Admin Theme isn’t ready for ThemeForest and cannot be resubmitted as it did not meet our minimum requirements for quality and/or Envato Market policies. In order for submissions to be considered for sale they must be of high aesthetic and technical quality, unique to our library and cannot be in violation of Envato’s policies.

Regrettably the Help and Quality Teams are unable to offer a critique or feedback on your rejected submission.

Please see our Help Center for more information: (https://)help.market.envato.com/hc/en-us/articles/204067134


Thanks for your submission!

Regards,

Envato Market Team


P.S. For your reference, here are the details from your submission.

Superial - Responsive Admin Theme

Introduction

Superial Admin has a big collection of material design animation & widgets, UI Elements, jQuery plugins and works on all major web browsers, tablets and phones. User friendly, intuitive, and fun to use.

Features

  • Responsive design (desktops, tablets, mobile devices)
  • Built with new Bootstrap 3.3.5
  • HTML5 & CSS3
  • Uses SASS
  • Source code grabber
  • 4 different charts libraries
  • Animations CSS3
  • 4 types of tables
  • Well-structured code
  • Amazing design
  • Mailbox, and mail detail
  • User profile
  • Widgets page
  • Material forms
  • Practical calendar view
  • Main Google material colors
  • Notifications
  • Register page
  • ?nd more other great components…

Credits

Twitter Bootstrap - css front-end framework.

AnimateCSS - Collection of CSS3 animations

Easypiechart - Jquery pie charts

Flot - simple but powerful chart plugin

Font Awesome - The iconic font and CSS toolkit

Google Material Icons - Material Icons

FullCalendar - A JavaScript event calendar.

Jquery UI - set of user interface interactions, effects, widgets, and themes built on top of the jQuery

MetisMenu - A jQuery menu plugin

MomentJs - Display dates in JavaScript.

Google material color - collection of colors

Simple Weather - current weather data for any location

jQuery slimScroll - nice scrollbar

Sparkline - small inline charts

Morris.js - good-looking charts shouldn’t be difficult

Chart.js - Simple, clean and engaging charts for designers and developers

Waves - Click effect for buttons

  • And many different jQuery solutions from author

admin template, dashboard, lightweight admin, material, material admin, material design, responsive admin, responsive dashboard

Thank you!

hi mvgroup777
well the quality of design not good enough and there general problems such as typography & white space