:root {
    --mdc-theme-primary: #2196F3;
    --mdc-theme-secondary: #FFC107;
    --mdc-theme-background: #f5f5f5;
    --mdc-theme-surface: #ffffff;
    --mdc-theme-on-primary: #ffffff;
    --mdc-theme-on-secondary: #000000;
    --mdc-theme-on-surface: #000000;
}

body {
    margin: 0;
    display: flex;
    flex-direction: column;
    min-height: 100vh;
    background-color: var(--mdc-theme-background);
    font-family: Arial, sans-serif;
    line-height: 1.6;
    color: #333;
}

.container {
    max-width: 1200px;
    width: 100%;
    margin: 0 auto;
    padding: 0 20px;
    box-sizing: border-box;
}

.site-header {
    background-color: var(--mdc-theme-primary);
    color: var(--mdc-theme-on-primary);
    padding: 40px 0;
    text-align: center;
}

.site-header h1 {
    margin-bottom: 10px;
}

.site-nav {
    background-color: var(--mdc-theme-surface);
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
}

.site-nav .container {
    display: flex;
    justify-content: center;
    padding: 10px 0;
}

.site-nav a {
    color: var(--mdc-theme-primary);
    text-decoration: none;
    padding: 10px 15px;
}

.site-nav a:hover {
    background-color: rgba(33, 150, 243, 0.1);
}

.site-main {
    flex-grow: 1;
    padding: 40px 0;
}

.app-section {
    background-color: var(--mdc-theme-surface);
    padding: 20px;
    border-radius: 5px;
    margin-bottom: 40px;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
}

.app-description {
    margin-bottom: 20px;
}

#file-input-container {
    display: flex;
    justify-content: space-between;
    margin-bottom: 20px;
    flex-wrap: wrap;
    gap: 10px;
}

#selected-files {
    max-height: 25em;
    overflow-y: auto;
    padding: 0;
    margin: 0;
    list-style: none;
}

#selected-files li {
    padding: 0.5em;
    border-bottom: 1px solid #ddd;
}

#selected-files li:last-child {
    border-bottom: none;
}

.mdc-list-item {
    padding: 12px 16px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    background-color: #f0f0f0;
    border-radius: 4px;
    margin-bottom: 8px;
}

.mdc-list-item__text {
    flex-grow: 1;
    margin-right: 16px;
}

.mdc-list-item__secondary-text {
    font-size: 0.875rem;
    color: rgba(0, 0, 0, 0.6);
}

#convertBtn {
    margin-bottom: 20px;
    width: 100%;
}

#result {
    text-align: center;
}

.seo-content {
    background-color: var(--mdc-theme-surface);
    padding: 20px;
    border-radius: 5px;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
}

.seo-content h2 {
    color: var(--mdc-theme-primary);
    border-bottom: 2px solid var(--mdc-theme-primary);
    padding-bottom: 10px;
    margin-top: 40px;
}

.seo-content section {
    margin-bottom: 30px;
}

.faq-item {
    margin-bottom: 20px;
}

.faq-item h3 {
    color: var(--mdc-theme-primary);
    margin-bottom: 10px;
}

.site-footer {
    background-color: var(--mdc-theme-primary);
    color: var(--mdc-theme-on-primary);
    text-align: center;
    padding: 20px 0;
    margin-top: 40px;
}

.site-footer a {
    color: var(--mdc-theme-on-primary);
}

@media (max-width: 768px) {
    .site-nav .container {
        flex-direction: column;
        align-items: center;
    }

    .site-nav a {
        padding: 10px 0;
        width: 100%;
        text-align: center;
    }

    #file-input-container {
        flex-direction: column;
    }

    #file-input-container button {
        width: 100%;
    }
}