:root {
    --navy: #102b4e;
    --navy-dark: #091b32;
    --orange: #f58220;
    --light: #f5f7fa;
    --text: #26364a;
    --muted: #6b7788;
    --white: #ffffff;
    --border: #e2e7ee;
}

* {
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    margin: 0;
    background: var(--light);
    color: var(--text);
    font-family: Arial, Helvetica, sans-serif;
    line-height: 1.6;
}

a {
    text-decoration: none;
    color: inherit;
}

button {
    font: inherit;
}

.site-header {
    background: var(--navy);
    color: white;
    border-bottom: 4px solid var(--orange);
}

.header-inner,
.hero-inner,
.gallery-section,
.footer-inner {
    width: min(1200px, calc(100% - 40px));
    margin: auto;
}

.header-inner {
    min-height: 86px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 25px;
}

.brand {
    display: flex;
    align-items: center;
    gap: 12px;
}

.brand-mark {
    width: 47px;
    height: 47px;
    display: grid;
    place-items: center;
    border-radius: 8px;
    background: var(--orange);
    color: white;
    font-size: 27px;
    font-weight: 800;
}

.brand-text strong,
.brand-text small {
    display: block;
}

.brand-text strong {
    font-size: 21px;
    line-height: 1.2;
}

.brand-text small {
    margin-top: 4px;
    color: #d6e1ef;
    font-size: 11px;
}

.main-nav {
    display: flex;
    flex-wrap: wrap;
    gap: 25px;
}

.main-nav a {
    color: white;
    font-size: 14px;
    font-weight: bold;
}

.main-nav a:hover {
    color: #ffb16b;
}

.hero {
    background: linear-gradient(115deg, #091b32, #163c69);
    color: white;
    padding: 76px 0 67px;
    position: relative;
    overflow: hidden;
}

.hero::after {
    content: "";
    position: absolute;
    width: 330px;
    height: 330px;
    border: 45px solid rgba(245, 130, 32, .12);
    border-radius: 50%;
    right: -90px;
    top: -120px;
    pointer-events: none;
}

.eyebrow {
    color: #ffb16b;
    text-transform: uppercase;
    font-size: 12px;
    font-weight: 800;
    letter-spacing: 2px;
    margin: 0 0 12px;
}

.hero h1 {
    font-size: clamp(34px, 5vw, 55px);
    line-height: 1.12;
    margin: 0 0 18px;
    letter-spacing: -1px;
}

.hero-description {
    max-width: 670px;
    color: #e0e9f4;
    font-size: 17px;
    margin: 0 0 26px;
}

.conference-info {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
}

.conference-info span {
    background: rgba(255, 255, 255, .09);
    border: 1px solid rgba(255, 255, 255, .17);
    border-radius: 5px;
    padding: 8px 12px;
    font-size: 12px;
}

.conference-theme {
    max-width: 780px;
    margin-top: 22px;
    color: #ffd0a7;
    font-size: 14px;
    font-style: italic;
}

.gallery-section {
    padding-top: 60px;
    padding-bottom: 75px;
}

.section-heading {
    display: flex;
    justify-content: space-between;
    align-items: end;
    gap: 25px;
    margin-bottom: 28px;
}

.orange-text {
    color: #d96a0c;
}

.section-heading h2 {
    color: var(--navy);
    font-size: clamp(27px, 4vw, 36px);
    line-height: 1.2;
    margin: 0 0 10px;
}

.section-description {
    color: var(--muted);
    margin: 0;
    max-width: 620px;
}

.photo-count {
    min-width: 155px;
    background: white;
    border: 1px solid var(--border);
    border-radius: 9px;
    padding: 13px 18px;
}

.photo-count strong,
.photo-count span {
    display: block;
}

.photo-count strong {
    color: var(--navy);
    font-size: 25px;
}

.photo-count span {
    color: var(--muted);
    font-size: 12px;
}

.filter-list {
    display: flex;
    flex-wrap: wrap;
    gap: 9px;
    margin-bottom: 30px;
}

.filter-link {
    border: 1px solid #d8dee7;
    background: white;
    color: var(--navy);
    border-radius: 5px;
    padding: 9px 15px;
    font-size: 13px;
    font-weight: 700;
    cursor: pointer;
    transition: background .2s, color .2s;
}

.filter-link:hover,
.filter-link.active {
    background: var(--navy);
    border-color: var(--navy);
    color: white;
}

.photo-grid {
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 25px;
}

.photo-card {
    background: white;
    border: 1px solid var(--border);
    border-radius: 9px;
    overflow: hidden;
    min-width: 0;
    box-shadow: 0 5px 18px rgba(16, 43, 78, .04);
    transition: transform .2s, box-shadow .2s;
}

.photo-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 12px 28px rgba(16, 43, 78, .12);
}

.photo-open {
    display: block;
    width: 100%;
    padding: 0;
    border: 0;
    background: #e9edf3;
    cursor: zoom-in;
    text-align: left;
}

.photo-image-wrap {
    display: block;
    position: relative;
    overflow: hidden;
    aspect-ratio: 4 / 3;
}

.photo-image-wrap img {
    display: block;
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform .35s;
}

.photo-card:hover .photo-image-wrap img {
    transform: scale(1.045);
}

.image-overlay {
    position: absolute;
    inset: 0;
    display: flex;
    align-items: center;
    justify-content: center;
    background: rgba(9, 27, 50, .68);
    color: white;
    opacity: 0;
    transition: opacity .25s;
    font-size: 14px;
    font-weight: 700;
}

.photo-card:hover .image-overlay,
.photo-open:focus-visible .image-overlay {
    opacity: 1;
}

.photo-details {
    padding: 18px 19px 20px;
}

.category-tag {
    display: inline-block;
    background: #fff0e3;
    color: #a94f00;
    border-radius: 4px;
    padding: 4px 8px;
    font-size: 10px;
    text-transform: uppercase;
    font-weight: 800;
}

.photo-details h3 {
    color: var(--navy);
    font-size: 18px;
    line-height: 1.35;
    margin: 12px 0 7px;
}

.photo-details p {
    margin: 0 0 12px;
    color: var(--muted);
    font-size: 13px;
}

.photo-date {
    color: #7c8797;
    font-size: 12px;
}

.no-results {
    text-align: center;
    padding: 50px 20px;
    background: white;
    border: 1px dashed #cbd4df;
    border-radius: 10px;
}

.no-results h3 {
    color: var(--navy);
}

.no-results p {
    color: var(--muted);
}

.site-footer {
    background: var(--navy-dark);
    color: white;
    padding: 30px 0;
}

.footer-inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 25px;
}

.footer-inner strong {
    color: #ffad64;
    font-size: 19px;
}

.footer-inner p {
    margin: 5px 0 0;
    color: #d0d9e5;
    font-size: 12px;
}

/* Full-screen photo preview */

.lightbox {
    display: none;
    position: fixed;
    inset: 0;
    z-index: 9999;
    align-items: center;
    justify-content: center;
    padding: 25px;
}

.lightbox.open {
    display: flex;
}

.lightbox-backdrop {
    position: absolute;
    inset: 0;
    background: rgba(3, 10, 20, .94);
}

.lightbox-dialog {
    position: relative;
    z-index: 1;
    width: min(100%, 1100px);
    max-height: 94vh;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 15px;
}

.lightbox-figure {
    margin: 0;
    min-width: 0;
    max-height: 94vh;
    text-align: center;
}

.lightbox-figure img {
    display: block;
    max-width: 100%;
    max-height: 76vh;
    margin: auto;
    object-fit: contain;
    border-radius: 5px;
}

.lightbox-figure figcaption {
    padding: 13px 10px 0;
    color: white;
}

.lightbox-figure h3 {
    margin: 0 0 5px;
    font-size: 19px;
}

.lightbox-figure p {
    margin: 0;
    color: #d5dce6;
    font-size: 13px;
}

.lightbox-close,
.lightbox-prev,
.lightbox-next {
    display: grid;
    place-items: center;
    flex: 0 0 auto;
    border: 1px solid rgba(255, 255, 255, .35);
    background: rgba(255, 255, 255, .12);
    color: white;
    cursor: pointer;
    border-radius: 50%;
}

.lightbox-close {
    position: absolute;
    top: -12px;
    right: -4px;
    width: 43px;
    height: 43px;
    font-size: 29px;
    z-index: 2;
}

.lightbox-prev,
.lightbox-next {
    width: 43px;
    height: 43px;
    font-size: 20px;
}

.lightbox-close:hover,
.lightbox-prev:hover,
.lightbox-next:hover {
    background: var(--orange);
}

body.lightbox-active {
    overflow: hidden;
}

[hidden] {
    display: none !important;
}

@media (max-width: 900px) {
    .photo-grid {
        grid-template-columns: repeat(2, minmax(0, 1fr));
        gap: 18px;
    }

    .section-heading {
        align-items: start;
    }
}

@media (max-width: 600px) {
    .header-inner {
        padding: 15px 0;
        flex-direction: column;
        align-items: flex-start;
    }

    .main-nav {
        gap: 18px;
    }

    .hero {
        padding: 50px 0;
    }

    .header-inner,
    .footer-inner,
    .hero-inner,
    .gallery-section {
        width: calc(100% - 28px);
    }

    .conference-info {
        flex-direction: column;
        align-items: flex-start;
    }

    .section-heading,
    .footer-inner {
        flex-direction: column;
        align-items: flex-start;
    }

    .photo-count {
        min-width: 0;
    }

    .photo-grid {
        grid-template-columns: 1fr;
        gap: 20px;
    }

    .photo-details {
        padding: 15px;
    }

    .lightbox {
        padding: 10px;
    }

    .lightbox-dialog {
        gap: 5px;
    }

    .lightbox-prev,
    .lightbox-next {
        width: 30px;
        height: 30px;
        font-size: 15px;
    }

    .lightbox-figure img {
        max-height: 70vh;
    }

    .lightbox-close {
        top: -42px;
        right: 0;
    }
}