/* Basic reset styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html, body {
    height: 100%; /* Ensure full height */
}

body {
    font-family: 'Helvetica Neue', Arial, sans-serif;
    margin: 0;
    padding: 0;
    background-color: #f0f4f8;
    color: #0f3252;
    line-height: 1.8;
    overflow-x: hidden;
    display: flex; /* Flex container for layout */
    flex-direction: column; /* Stack children vertically */
}

/* Header styling */
header {
    background-color: white;
    color: #004080;
    padding: 20px 0;
    display: flex;
    justify-content: space-between;
    align-items: center;
    box-shadow: 0 2px 5px rgba(0, 0, 0, 0.1);
}

header .logo img {
    max-width: 150px;
    transition: transform 0.3s ease;
}

header .logo img:hover {
    transform: scale(1.05);
}

nav ul {
    display: flex;
    gap: 20px;
    list-style-type: none;
}

nav ul li a {
    color: #004080;
    text-decoration: none;
    font-weight: bold;
    padding: 10px 15px;
    transition: background-color 0.3s ease, color 0.3s ease;
}

nav ul li a:hover {
    background-color: rgba(0, 64, 128, 0.1);
    border-radius: 5px;
}

/* Main content */
main {
    padding: 60px 5%;
    max-width: 1200px;
    margin: 0 auto;
    flex: 1; /* Allow main to grow and push footer down */
}

/* Upload Section Styling */
.upload-section {
    background: #ffffff;
    padding: 40px;
    margin: 40px auto;
    border-radius: 20px;
    box-shadow: 0 4px 10px rgba(0, 0, 0, 0.1);
    max-width: 600px;
    text-align: center;
}

.upload-section h2 {
    font-size: 2rem;
    color: #004080;
    margin-bottom: 15px;
}

.upload-section p {
    font-size: 1rem;
    color: #666;
    margin-bottom: 20px;
}

.upload-section label {
    font-weight: bold;
    color: #004080;
    display: block;
    margin-bottom: 10px;
}

.upload-section input[type="file"] {
    display: inline-block;
    padding: 10px;
    font-size: 1rem;
    border: 1px solid #ddd;
    border-radius: 5px;
    margin-bottom: 20px;
    background-color: #f9f9f9;
    cursor: pointer;
    width: 100%;
    max-width: 300px;
    transition: border-color 0.3s ease, background-color 0.3s ease;
}

.upload-section input[type="file"]:hover {
    border-color: #004080;
    background-color: #f1f9ff;
}

.upload-section button {
    background-color: #004080;
    color: white;
    padding: 10px 20px;
    border: none;
    border-radius: 5px;
    cursor: pointer;
    transition: background-color 0.3s ease, transform 0.3s ease;
}

.upload-section button:hover {
    background-color: #00264d;
    transform: scale(1.05);
}

#file-size-warning {
    font-size: 0.9rem;
    color: #d9534f; /* Red for error */
    display: none; /* Hidden by default */
}

/* Footer styling */
footer {
    background: white;
    color: #004080;
    padding: 50px 0;
    text-align: center;
    font-size: 0.95rem;
    box-shadow: 0 -2px 5px rgba(0, 0, 0, 0.1);
}

@media only screen and (max-width: 768px) {
    header {
        flex-direction: column;
        align-items: center;
    }

    nav ul {
        flex-direction: column;
        gap: 10px;
    }

    main {
        padding: 30px;
    }

    .upload-section {
        padding: 20px;
    }

    .upload-section h2 {
        font-size: 1.5rem;
    }

    .upload-section p {
        font-size: 0.9rem;
    }

    .upload-section input[type="file"] {
        font-size: 0.9rem;
        max-width: 100%;
    }

    .upload-section button {
        font-size: 0.9rem;
        padding: 8px 16px;
    }

    footer {
        font-size: 0.85rem;
    }
}