body {
    font-family: Arial, sans-serif;
    background: #f0f2f5;
    display: flex;
    justify-content: center;
    align-items: center;
    flex-direction: column;
    padding: 2em;
}

.message-panel {
    text-align: center;
}

.form-title {
    margin-top: 0;
    margin-bottom: 1em;
}

.uploader {
    background: white;
    padding: 2rem;
    border-radius: 10px;
    box-shadow: 0 0 12px rgba(0, 0, 0, 0.1);
    /* text-align: center; */
}

.file-label {
    display: inline-block;
    border: 1px solid #007bff;
    background-color: #fff;
    color: #007bff;
    padding: 10px 20px;
    border-radius: 8px;
    cursor: pointer;
    margin-bottom: 1rem;
    transition: background-color 0.3s ease, color 0.3s ease;
}

.file-label:hover {
    background-color: #007bff;
    color: #fff;
}

input[type="file"] {
    display: none;
}

.submit-btn {
    background: #28a745;
    color: white;
    padding: 10px 20px;
    border: none;
    border-radius: 8px;
    cursor: pointer;
    opacity: 0.5;
    pointer-events: none;
    transition: 0.3s;
    font-size: 16px;
}

.submit-btn.enabled {
    opacity: 1;
    pointer-events: auto;
}

.filename {
    margin-top: 10px;
    color: #333;
    font-size: 0.9rem;
}

button:disabled {
    background-color: #ccc;
    /* light gray background */
    color: #666;
    /* dim text */
    cursor: not-allowed;
    /* show forbidden cursor */
    opacity: 0.6;
    /* optional: faded look */
}

.spinner {
    border: 2px solid #f3f3f3;
    border-top: 2px solid #555;
    border-radius: 50%;
    width: 16px;
    height: 16px;
    animation: spin 1s linear infinite;
    display: inline-block;
    margin-left: 8px;
    vertical-align: middle;
}

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

    100% {
        transform: rotate(360deg);
    }
}