*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

#header {
    background-color: #333;
    color: white;
    padding: 10px 30px;
    text-align: center;
    display: flex;
    font-family: sans-serif;
    font-size: 100%;
    align-items: center;
    height: 90px;
}
#header h1 {
    font-weight: 700;
    font-family: sans-serif;
    font-size: 1.5rem;
    margin-left: auto;
}
#header .burger {
    margin-left: auto;
}
#header .burger-menu {
    background-color: #333;
    color: white;
    border: none;
    font-size: 32px;
    cursor: pointer;
}
#header .burger-menu-items {
    list-style: none;
    padding: 0;
    margin: 0;
    position: absolute;
    right: 10px;
    top: 70px;
    background-color: #333;
    display: none;
    font-size: 130%;
}
#header .burger-menu-items li {
    padding: 10px;
}
#header .burger-menu-items li a {
    color: white;
    text-decoration: none;
}
#header .burger-menu-items li a:hover {
    background-color: #555;
}

#footer {
    background-color: #333;
    color: white;
    padding: 10px;
    text-align: center;
    margin-top: 20px;
}

/* ── Home page ── */
#content {
    display: flex;
    gap: 20px;
    flex-wrap: wrap;
    margin-top: 50px;
    margin-left: 120px;
    margin-right: 120px;
}
#content .section {
    flex: 1;
    min-width: 200px;
    text-align: center;
}
#content .catalog {
    background-color: #4CAF50;
    color: white;
    padding: 10px 20px;
    border: none;
    cursor: pointer;
    margin-top: 20px;
}
#content .catalog:hover {
    background-color: #45a049;
}
#content .contact {
    background-color: #008CBA;
    color: white;
    padding: 10px 20px;
    border: none;
    cursor: pointer;
    margin-top: 20px;
}
#content .contact:hover {
    background-color: #007bb5;
}

#catalog-preview {
    background-color: #008CBA;
    padding: 20px;
    margin-left: 180px;
    margin-right: 180px;
    margin-top: 40px;
    align-items: center;
    text-align: center;
}

/* ── Contact page ── */
.contact-container {
    background-color: #f4f4f4;
    padding: 20px;
    margin: 20px auto 0;
    align-items: center;
    text-align: center;
    max-width: 600px;
}
.contact-container form {
    display: flex;
    flex-direction: column;
    gap: 15px;
    max-width: 620px;
}
.contact-container label,
.contact-container input,
.contact-container textarea {
    width: 100%;
    box-sizing: border-box;
}
.contact-container button {
    align-self: flex-end;
}

/* ── About page ── */
.about-container {
    padding: 20px;
    margin: 0 auto;
    align-items: center;
    text-align: left;
    max-width: 600px;
}
.about-container h1 {
    text-align: left;
    padding-left: 20px;
}
.about-container #about-blurb {
    background-color: #007bb5;
    padding: 20px;
    margin-top: 10px;
    text-align: left;
}
.about-container #about-technical {
    background-color: #4CAF50;
    padding: 20px;
    margin-top: 10px;
    text-align: left;
}

/* ── Catalog page ── */
.catalog-page {
    font-family: Georgia, 'Times New Roman', serif;
    min-height: 100vh;
}
.catalog-page .page {
    max-width: 900px;
    margin: 0 auto;
    padding: 28px 20px 60px;
}
.catalog-page .page h1 {
    font-size: 2.6rem;
    font-weight: 400;
    font-family: Georgia, 'Times New Roman', serif;
    letter-spacing: -0.5px;
    margin-bottom: 20px;
}
.filter-bar {
    display: flex;
    align-items: center;
    margin-bottom: 18px;
}
.tab-group {
    display: flex;
    border: 1.5px solid #1a1a1a;
    border-radius: 4px;
    overflow: hidden;
}
.tab {
    padding: 6px 16px;
    font-size: 0.85rem;
    font-family: inherit;
    background: #fff;
    border: none;
    border-right: 1.5px solid #1a1a1a;
    cursor: pointer;
    transition: background 0.15s, color 0.15s;
}
.tab:last-child { border-right: none; }
.tab.active { background: #1a1a1a; color: #fff; }
.tab:hover:not(.active) { background: #eee; }
.sort-btn {
    margin-left: auto;
    background: none;
    border: 1.5px solid #1a1a1a;
    border-radius: 4px;
    padding: 6px 10px;
    cursor: pointer;
    display: flex;
    align-items: center;
    gap: 4px;
    font-size: 0.8rem;
    font-family: inherit;
    transition: background 0.15s;
}
.sort-btn:hover { background: #eee; }
.catalog-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 5px;
}
.catalog-grid .card {
    aspect-ratio: 2/2;
    background: #fff;
    overflow: hidden;
    position: relative;
}
.catalog-grid .card img {
    width: 100%;
    height: 200%;
    object-fit: cover;
    display: block;
    transition: transform 0.2s ease;
}
.catalog-grid .card:hover img { transform: scale(1.04); }
.catalog-grid .card.hidden { display: none; }
.load-more-row {
    margin-top: 24px;
    display: flex;
    align-items: center;
    gap: 16px;
}
.load-more-btn {
    padding: 8px 22px;
    border: 1.5px solid #1a1a1a;
    background: #fff;
    font-family: inherit;
    font-size: 0.85rem;
    border-radius: 4px;
    cursor: pointer;
    transition: background 0.15s, color 0.15s;
}
.load-more-btn:hover { background: #1a1a1a; color: #fff; }
.load-more-btn:disabled { opacity: 0.4; cursor: default; }
.load-more-row span {
    font-size: 0.8rem;
    color: #888;
}