body {
    font-family: 'Arial', sans-serif;
    background: linear-gradient(135deg, #f5f7fa, #c3cfe2);
    text-align: center;
    padding: 20px;
}

.container {
    max-width: 600px;
    margin: 50px auto;
    background: white;
    padding: 20px;
    border-radius: 10px;
    box-shadow: 0px 4px 10px rgba(0, 0, 0, 0.1);
}

h1 {
    color: #333;
}

button {
    background: #D3D3D3;
    color: black;
    padding: 10px 15px;
    border: none;
    cursor: pointer;
    border-radius: 5px;
    transition: background 0.3s;
}

button:hover {
    background: #FEDD00;
}

input[type="file"] {
    margin-top: 10px;
    padding: 5px;
    border: 1px solid #ccc;
    border-radius: 5px;
}

.overlay {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.5);
    z-index: 9999;
}

.spinner {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 50px;
    height: 50px;
    border: 6px solid #f3f3f3;
    border-top: 6px solid #3498db;
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

@keyframes spin {
    0% {
        transform: rotate(0deg);
    }
    100% {
        transform: rotate(360deg);
    }
}

#downloadBtn {
    display: none;
    margin: 20px auto auto auto;
    padding: 10px 20px;
    background: #F58220;
    color: white;
    border: none;
    border-radius: 5px;
    cursor: pointer;
    text-decoration: none;
    width: auto;
    white-space: nowrap;
    position: relative;
}

.logo {
    display: block;
    margin: 0 auto;
    max-width: 200px;
    height: auto;
}