feat: everything's max-width 768px

public/index.html

src/components/bottom-sheet/BottomSheet.module.css

src/components/header/Header.module.css

src/components/toast/Toast.module.css

src/index.css

src/pages/cart-page/CartPage.module.css

src/pages/cart-page/CartPage.tsx

src/pages/history-page/modules/order-box/OrderBox.module.css

src/pages/login-page/LoginPage.module.css

src/pages/menu-page/modules/menu-box/MenuBox.module.css

src/pages/order-page/module/ExitButton.module.css

src/pages/signup-page/SignupPage.module.css