Shine Hover Effect Button

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Shine on Hover Effect Button</title>
    <style>
        /*
         Component: Shine on Hover Button
         Description: A button with a glossy sheen that animates across on hover.
        */
        :root {
            --shine-btn-bg: #343a40;
            --shine-btn-text-color: #ffffff;
            --shine-focus-outline: #343a40;
            --shine-speed: 0.75s;
        }
        
        .shine-container-1 {
            font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
            display: flex;
            justify-content: center;
            align-items: center;
            padding: 2rem;
            background-color: #f8f9fa;
        }

.shine-btn-1 {
            position: relative; /* Needed to position the pseudo-element */
            overflow: hidden;   /* Essential to clip the shine effect */
            
            display: inline-block;
            padding: 1rem 2rem;
            font-size: 1.1rem;
            font-weight: 600;
            
            color: var(--shine-btn-text-color);
            background-color: var(--shine-btn-bg);
            border: none;
            border-radius: 8px;
            cursor: pointer;
            text-decoration: none;
        }

/* The shine effect pseudo-element */
        .shine-btn-1::before {
            content: '';
            position: absolute;
            top: 0;
            left: -100%; /* Start off-screen */
            width: 100%;
            height: 100%;
            
            /* The angled sheen created with a gradient */
            background-image: linear-gradient(
                120deg,
                rgba(255, 255, 255, 0) 30%,
                rgba(255, 255, 255, 0.4),
                rgba(255, 255, 255, 0) 70%
            );
            
            transition: left var(--shine-speed) ease-in-out;
        }
        
        /* On hover, move the shine element across the button */
        .shine-btn-1:hover::before {
            left: 100%; /* Move to the other side */
        }
        
        .shine-btn-1:focus-visible {
            outline: 3px solid var(--shine-focus-outline);
            outline-offset: 3px;
        }
    </style>
</head>
<body>

<div class="shine-container-1">
        <button type="button" class="shine-btn-1">Unlock Premium</button>
    </div>

</body>
</html>