* {
    box-sizing: border-box;
}

body {
    font-family: Arial, sans-serif;
    margin: 0;
    padding: 0;
    background-color: #f7f7f7;
    color: #444;
    text-align: center;
}

a {
    color: #0066cc;
}

.container {
    max-width: 960px;
    margin: 0 auto;
    padding: 2em;
}

header {
    margin-bottom: 3em;
}

h1 {
    font-size: 3em;
    margin: 0;
}

h2 {
    font-size: 2em;
    margin: 0 0 1em 0;
}

button {
    background-color: #0066cc;
    color: #fff;
    border: none;
    padding: 0.8em 1.5em;
    border-radius: 5px;
    cursor: pointer;
    transition: all 0.3s ease;
}

button:hover {
    background-color: #0052a3;
}

input[type="text"],
input[type="file"] {
    padding: 0.6em;
    border: none;
    border-radius: 5px;
    background-color: #fff;
    margin-right: 1em;
    margin-bottom: 1em;
    box-shadow: 0px 1px 3px rgba(0, 0, 0, 0.1);
}

input[type="file"] {
    cursor: pointer;
}

label {
    font-weight: bold;
    display: block;
    margin-bottom: 0.5em
}

form {
    margin-top: 2em;
}

.upload,
.download {
    width: 45%;
    margin-top: 2em;
    margin-left: 250px;
    padding: 1em;
    border: 1px solid #ccc;
    border-radius: 5px;
    box-shadow: 0px 1px 3px rgba(0, 0, 0, 0.1);
}

.progress-bar {
    height: 20px;
    background-color: #eee;
    border-radius: 10px;
    position: relative;
    overflow: hidden;
    display: none;
    animation: animate-progress 2s ease-out forwards;

    @keyframes animate-progress {
        0% {
            width: 0;
        }

        100% {
            width: 100%;
        }
    }
}

.progress-bar-inner {
    height: 100%;
    background-color: #4CAF50;
    border-radius: 10px;
    width: 0;
    position: absolute;
    transition: width 0.3s ease-in-out;
}

#upload-button,
#download-button {
    font-size: 1.2em;
    margin-bottom: 1em;
}

#download-info {
    margin-top: 1em;
    font-size: 0.8em;
}

.hidden {
    display: none;
}