Header Offcanvas Collapse

<!--Header Start-->
<header class="z-fixed">
    <nav class="navbar navbar-expand-lg navbar-light">
        <div class="container position-relative">
            <!--:Brand Logo:-->
            <a class="navbar-brand" href="index.html">
                <img src="assets/img/logo/logo.svg" alt="" class="img-fluid navbar-brand-light">
                <img src="assets/img/logo/logo-white.svg" alt="" class="img-fluid navbar-brand-dark">
            </a>
            <div class="d-flex align-items-center navbar-no-collapse-items order-lg-last">
                <button class="navbar-toggler order-last" type="button" data-bs-toggle="offcanvas"
                    data-bs-target="#mainNavbarTheme" aria-controls="mainNavbarTheme" aria-expanded="false"
                    aria-label="Toggle navigation">
                    <span class="navbar-toggler-icon">
                        <i></i>
                    </span>
                </button>
                <div class="nav-item me-3 me-lg-0">
                    <a href="#" class="btn btn-sm btn-primary rounded-pill">
                        Purchase

                    </a>
                </div>
            </div>
            <div class="offcanvas-lg offcanvas-navbar offcanvas-start" id="mainNavbarTheme">
                <!--Offcanvas collapse close button-->
                <div class="offcanvas-header justify-content-end p-0">
                    <button class="btn btn-secondary px-2 py-1 rounded-top-end-0" data-bs-target="#mainNavbarTheme"
                        data-bs-dismiss="offcanvas">
                        <i class="bx bx-x fs-4"></i>
                    </button>
                </div>
                <div class="offcanvas-body">
                    <!--Navbar items-->
                    <ul class="navbar-nav ms-auto">
                        <li class="nav-item">
                            <a class="nav-link" href="#">Home</a>
                        </li>
                        <li class="nav-item">
                            <a class="nav-link" href="#">About</a>
                        </li>
                        <li class="nav-item dropdown">
                            <a class="nav-link dropdown-toggle" href="#" data-bs- toggle="dropdown">Dropdown Nav</a>
                            <div class="dropdown-menu dropdown-menu-end">
                                <a href="#" class="dropdown-item">Dropdown item</a>
                                <a href="#" class="dropdown-item">Dropdown item</a>
                                <a href="#" class="dropdown-item">Dropdown item</a>
                                <a href="#" class="dropdown-item">Dropdown item</a>
                            </div>
                        </li>
                        <li class="nav-item">
                            <a class="nav-link" href="#">Projects</a>
                        </li>
                        <li class="nav-item">
                            <a class="nav-link" href="#">Contact</a>
                        </li>
                    </ul>
                </div>
            </div>
        </div>
    </nav>
</header>