Many thanks to the creators of icons, tools, etc. used on this website。
アイコンなどの作った人、ありがとう！

Icons

• Pdf icons created by Dimitry Miroliubov - Flaticon
• Unmute icons created by Fathema Khanom - Flaticon
• Refresh icons created by srip - Flaticon
• Light bulb icons created by Freepik - Flaticon
• Preparation icons created by Mehwish - Flaticon
• Medal icons created by Vectors Market - Flaticon
• Arrow icons created by Kirill Kazachek - Flaticon
• Newspaper icons created by Freepik - Flaticon
• Book icons created by Freepik - Flaticon
• Course icons created by Freepik - Flaticon
• Calendar icons created by DinosoftLabs - Flaticon
• Youtube icons created by Freepik - Flaticon
• Tweet icons created by Freepik - Flaticon
• Checklist icons created by Freepik - Flaticon
• Multimedia icons created by Freepik - Flaticon
• Sticker icons created by Milkghost Studio - Flaticon
• Teacher icons created by Rashad - Flaticon
• Dialog icons created by Pixel Buddha Premium - Flaticon
• Conversation icons created by Freepik - Flaticon
• Coin icons created by Heykiyou - Flaticon
• Kindergarten icons created by Freepik - Flaticon
• Rss icons created by riajulislam - Flaticon
• Document icons created by smalllikeart - Flaticon
• Marketplace icons created by Freepik - Flaticon
• Product icons created by hqrloveq - Flaticon

Web Development

• TCPDF - Open Source PHP class for generating PDF documents
• CodeShack.io - Super-fast PHP MySQL Database Class by David Adams
• Inspekt - A filtering and validation library for PHP, created by Ed Finkler and maintained by Ben Edmunds.
• Bootstrap - A front-end development framework for building websites.
• WampServer - Windows web development environment.