Change font on admin panel

Hi,

I want to change the font for our backend, so that it uses a font that supports a unicode character for currency
I have added the font files to design > backend > media > fonts

and added this in my styles.less as per the instructions on

// =================================================================
// CS-Cart Admin Panel Styles
// =================================================================

// -------------------------
// Font Faces
// -------------------------
@font-face {
font-family: ‘MuseoSansBlack’;
src: url(‘…/media/fonts/MuseoSansBlack.eot’);
src: url(‘…/media/fonts/MuseoSansBlack.eot?#iefix’) format(‘embedded-opentype’),
url(‘…/media/fonts/MuseoSansBlack.woff’) format(‘woff’),
url(‘…/media/fonts/MuseoSansBlack.ttf’) format(‘truetype’);
font-weight: normal;
font-style: normal;
font-display: swap;
}

// -------------------------
// Typography
// -------------------------
@sansFontFamily: ‘MuseoSansBlack’, -apple-system, BlinkMacSystemFont, San Francisco, Roboto, Segoe UI, Ubuntu, Helvetica Neue, sans-serif;
@serifFontFamily: Georgia, “Times New Roman”, Times, serif;
@monoFontFamily: Monaco, Menlo, Consolas, “Courier New”, monospace;

// -------------------------
// Global Styles
// -------------------------
body {
font-family: @sansFontFamily !important;
font-size: 14px;
color: #333;
background-color: #f8f9fa;
}

// -------------------------
// Headings
// -------------------------
h1, h2, h3, h4, h5, h6 {
font-family: @sansFontFamily;
font-weight: bold;
color: #222;
}

// -------------------------
// Forms & Inputs
// -------------------------
input, textarea, select, button {
font-family: @sansFontFamily;
font-size: 14px;
}

// -------------------------
// Buttons
// -------------------------
.btn {
font-family: @sansFontFamily;
font-size: 14px;
font-weight: 600;
border-radius: 4px;
}

// -------------------------
// Sidebar
// -------------------------
.sidebar {
font-family: @sansFontFamily;
}

// -------------------------
// Other Elements (Optional Tweaks)
// -------------------------
.navbar, .dropdown-menu, .modal {
font-family: @sansFontFamily;
}

However, on cs-cart 4.18.2 the font on the admin panel does not seem to change, and the unicode character isnt properly displayed