body {
    font-family: Arial, sans-serif;
    margin: 0;
    padding: 0;
    background-color: #f4f4f4;
    color: #333;
}

header {
    background-color: #333;
    color: #fff;
    padding: 1em 0;
    text-align: center;
}

nav ul {
    list-style: none;
    padding: 0;
}

nav ul li {
    display: inline;
    margin: 0 10px;
}

nav ul li a {
    color: #fff;
    text-decoration: none;
}

main {
    padding: 20px;
    max-width: 800px;
    margin: 20px auto;
    background-color: #fff;
    border-radius: 8px;
    box-shadow: 0 0 10px rgba(0, 0, 0, 0.1);
}

footer {
    text-align: center;
    padding: 20px;
    background-color: #333;
    color: #fff;
    position: relative;
    bottom: 0;
    width: 100%;
}

.portfolio-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 20px;
    margin-top: 20px;
}

.portfolio-item {
    display: flex;
    flex-direction: column;
    align-items: center;
    text-align: center;
}

.portfolio-item .app-icon {
    display: flex;
    justify-content: center;
    align-items: center;
    width: 100px;
    height: 100px;
    background-color: #f9f9f9;
    border: 1px solid #ddd;
    border-radius: 20px;
    box-shadow: 0 2px 5px rgba(0,0,0,0.05);
    overflow: hidden;
    text-decoration: none;
}

.portfolio-item .app-icon img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    border-radius: 20px;
}

.portfolio-item .app-subtitle {
    margin: 8px 0 0 0;
    color: #333;
    font-size: 0.9em;
}

.tabs {
    display: flex;
    border-bottom: 2px solid #ddd;
    margin-bottom: 20px;
}

.tab-button {
    padding: 10px 20px;
    background: none;
    border: none;
    cursor: pointer;
    font-size: 16px;
    color: #666;
    border-bottom: 2px solid transparent;
    margin-bottom: -2px;
    transition: all 0.3s ease;
}

.tab-button:hover {
    color: #333;
}

.tab-button.active {
    color: #333;
    border-bottom: 2px solid #333;
}

.tab-content {
    display: none;
}

.tab-content.active {
    display: block;
}

.tab-content h1 {
    font-size: 1.8em;
    margin-bottom: 4px;
}

.tab-content h2 {
    font-size: 1.15em;
    margin-top: 32px;
    margin-bottom: 6px;
}

.tab-content p {
    margin: 8px 0;
    line-height: 1.7;
}

.tab-content .updated {
    color: #888;
    font-size: 0.9em;
    margin-bottom: 32px;
}

.tab-content a {
    color: #1a6fca;
}