body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, 'Open Sans', 'Helvetica Neue', sans-serif;
    margin: 0;
    padding: 0;
    background-color: #fafafa;
    color: #444;
    line-height: 1.6;
}

a:focus, button:focus {
    outline: 2px solid #007bff;
    outline-offset: 2px;
}

header {
    background: #f0f0f0;
    color: #555;
    padding: 30px 0;
    text-align: center;
    border-bottom: 1px solid #e0e0e0;
}

header h1 {
    margin: 0;
    font-size: 2.8em;
    font-weight: 600;
}

header p {
    margin: 8px 0 0;
    font-size: 1.1em;
    color: #777;
}

.container {
    max-width: 1100px;
    margin: 30px auto;
    padding: 0 20px;
}

.portfolio-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 25px;
}

.portfolio-item {
    background: #fff;
    border: 1px solid #e5e5e5;
    border-radius: 12px;
    overflow: hidden;
    box-shadow: 0 6px 10px rgba(0, 0, 0, 0.05);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.portfolio-item:hover {
    transform: translateY(-8px);
    box-shadow: 0 10px 20px rgba(0, 0, 0, 0.1);
}

.portfolio-item .placeholder {
    width: 100%;
    height: 350px;
    background: linear-gradient(135deg, #ececec, #f5f5f5);
    position: relative;
    overflow: hidden;
}

.portfolio-item .placeholder video {
    position: absolute;
    top: 50%;
    left: 50%;
    width: 100%;
    height: 100%;
    object-fit: cover;
    transform: translate(-50%, -50%);
}

.portfolio-item h3 {
    margin: 20px 15px;
    font-size: 1.25em;
    text-align: center;
    color: #555;
}

footer {
    text-align: center;
    padding: 30px 0;
    background: #f5f5f5;
    color: #666;
    margin-top: 50px;
    border-top: 1px solid #e0e0e0;
}

footer a {
    color: #777;
    text-decoration: none;
    font-weight: 500;
}

footer a:hover {
    text-decoration: underline;
}

@media (max-width: 768px) {
    .portfolio-grid {
        #grid-template-columns: 1fr;
    }

    header h1 {
        font-size: 2em;
    }
}