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

body { font-family: Arial, Helvetica, sans-serif; background: #f8f8f8; color: #333; }

.container { max-width: 1200px; margin: 0 auto; padding: 0 20px; }



/* Unified header - same on all pages */

header { background: #fff; border-bottom: 1px solid #e0e0e0; padding: 20px 0; }

.header-inner { display: flex; justify-content: space-between; align-items: center; flex-wrap: wrap; gap: 15px; }

.logo { display: flex; align-items: center; gap: 15px; }

.logo img { height: 50px; }

.logo-text { font-size: 18px; font-weight: bold; color: #333; }

nav { display: flex; align-items: center; gap: 20px; flex-wrap: wrap; }

nav a { color: #333; text-decoration: none; font-size: 14px; }

nav a:hover { color: #007bff; }

nav a.active { color: #007bff; font-weight: bold; }



.breadcrumbs { padding: 15px 0; font-size: 13px; color: #666; }

.breadcrumbs a { color: #666; text-decoration: none; }



.main-wrapper { display: flex; gap: 30px; margin: 20px 0; }

.main-content { flex: 1; background: #fff; padding: 30px; }

.sidebar { width: 300px; flex-shrink: 0; }



h1 { font-size: 26px; margin-bottom: 20px; color: #333; }

h2 { font-size: 20px; margin: 25px 0 15px; color: #333; }

p { margin-bottom: 15px; line-height: 1.6; }

ul { margin: 15px 0 15px 25px; }

li { margin-bottom: 8px; }

a { color: #007bff; }



.sidebar-box { background: #fff; margin-bottom: 10px; border: 1px solid #e0e0e0; overflow: hidden; }

.sidebar-nav { list-style: none; margin: 0; padding: 0; }

.sidebar-nav li { margin: 0; border-bottom: 1px solid #eee; }

.sidebar-nav a { display: block; padding: 15px 20px; color: #333; text-decoration: none; }

.sidebar-nav a.active { background: #0078d4; color: #fff; }

.sidebar-nav a:hover:not(.active) { background: #f5f5f5; }



.sidebar-logos { background: #7daacc; padding: 15px; text-align: center; display: flex; justify-content: center; gap: 15px; align-items: center; flex-wrap: wrap; }

.sidebar-logos img {max-width: 250px; object-fit: contain; }



.special-issue-green { background: linear-gradient(180deg, #2e7d32 0%, #388e3c 50%, #1b5e20 100%); color: #fff; padding: 25px; }

.special-issue-green h4 { font-size: 16px; margin-bottom: 15px; }

.special-issue-green p { font-size: 13px; margin: 5px 0; }

.special-issue-green .special-label { font-size: 20px; font-weight: bold; margin-top: 15px; }

.special-issue-green .invitation { font-size: 12px; opacity: 0.9; }

/* Sidebar: link z grafiką (Special Issue) – sam link ma klasę .sidebar-box.special-issue-green */
a.sidebar-box.special-issue-green { display: block; color: inherit; text-decoration: none; padding: 25px; text-align: center; }
a.sidebar-box.special-issue-green:hover { opacity: 0.95; }
a.sidebar-box.special-issue-green img { max-width: 100%; height: auto; display: block; margin: 0 auto; }

/* Important dates – prawa kolumna */
.important-dates { padding: 20px; background: #f9f9f9; border: 1px solid #e0e0e0; margin-bottom: 20px; }
.important-dates h3 { font-size: 16px; margin-bottom: 15px; color: #333; font-weight: bold; }
.important-dates-table { width: 100%; border-collapse: collapse; font-size: 14px; margin-bottom: 18px; }
.important-dates-table td { padding: 10px 12px; border-bottom: 1px solid #eee; }
.important-dates-table tr:nth-child(even) { background: #f0f0f0; }
.important-dates-table .date-col { text-align: right; font-weight: bold; color: #0078d4; }
.important-dates-table tr.highlight td { color: #c00; font-weight: bold; }
.important-dates-table tr.highlight .date-col { color: #c00; }
.important-dates p { font-size: 13px; line-height: 1.5; margin: 12px 0; color: #333; }
.important-dates p a { color: #0078d4; }



.committee-list { margin: 15px 0; }

.committee-list p { margin: 5px 0; }

.committee-list strong { display: block; margin-top: 15px; }



table { width: 100%; border-collapse: collapse; margin: 20px 0; }

th, td { border: 1px solid #ddd; padding: 12px; text-align: left; }

th { background: #f5f5f5; font-weight: bold; }

.fees-table th.fees-title { background: transparent; color: #c00;  font-weight: bold; }
.fees-table thead tr:first-child th { color: #c00; }
.fees-table thead tr:first-child th .fees-header-sub { color: #222222; }
.fees-table tbody tr:nth-child(even) { background: #f5f5f5; }
.fees-table tbody tr:nth-child(odd) { background: #fff; }
.table-note { font-size: 13px; color: #666; margin-top: 10px; font-style: italic; }

footer { background: #333; color: #fff; padding: 20px 0; margin-top: 40px; }

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

.footer-content p { font-size: 13px; }

footer a { color: #ccc; text-decoration: none; }
footer a:hover, footer a:active, footer a:focus { color: #fff; }



.btn { display: inline-block; padding: 12px 25px; background: #0078d4; color: #fff; text-decoration: none; margin: 5px 10px 5px 0; font-size: 14px; }

.btn:hover { background: #005a9e; }



.keynote-item, .tutorial-item { margin: 30px 0; padding-bottom: 30px; border-bottom: 1px solid #eee; }

.keynote-item:last-child, .tutorial-item:last-child { border-bottom: none; }

.keynote-item h3, .tutorial-item h3 { font-size: 20px; margin-bottom: 10px; }

.keynote-item .author, .tutorial-item .author { color: #666; font-size: 14px; margin-bottom: 15px; }

.keynote-item .bio-wrapper, .tutorial-item .bio-wrapper, .main-content .bio-wrapper { display: flex; gap: 20px; margin: 15px 0; }

.keynote-item .bio-wrapper img, .tutorial-item .bio-wrapper img, .main-content .bio-wrapper img { width: 120px; height: 120px; object-fit: cover; flex-shrink: 0; }

/* Ograniczenie dużych zdjęć/screenshotów na stronach prelegentów */
.main-content > img { max-width: 500px; width: 100%; height: auto; display: block; margin-bottom: 20px; }

.video-section {
    margin-bottom: 40px;
}

.video-section h3 {
    color: #1e3a5f;
    margin-bottom: 15px;
}

.video-thumbnail-link {
    display: block;
    position: relative;
    max-width: 640px;
    overflow: hidden;
    border-radius: 8px;
    box-shadow: 0 2px 8px rgba(0,0,0,0.15);
}

.video-thumbnail {
    width: 100%;
    height: auto;
    display: block;
    vertical-align: top;
}

.video-play-overlay {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 68px;
    height: 48px;
    background: rgba(0,0,0,0.7);
    border-radius: 12px;
    color: #fff;
    font-size: 24px;
    line-height: 48px;
    text-align: center;
    padding-left: 4px;
    box-sizing: border-box;
    transition: background 0.3s;
}

.video-thumbnail-link:hover .video-play-overlay {
    background: rgba(204,0,0,0.9);
}

.video-container {
    position: relative;
    padding-bottom: 56.25%;
    height: 0;
    overflow: hidden;
    margin-bottom: 15px;
}

.video-container iframe {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
}