/* Header Layout - Corrected to match WWW2024 exactly and positioned at TOP */

/* CRITICAL: Ensure header is at the very top of the page */
header {
    background-color: var(--white);
    padding: 10px 0;
    width: 100% !important;
    position: sticky !important;
    top: 0 !important;
    left: 0 !important;
    z-index: 1000 !important;
    border-bottom: 1px solid var(--dark-grey);
    /* CRITICAL: Remove any margin that pushes header down */
    margin: 0 !important;
}

/* Main header container - centered with max-width */
.header-container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
    width: 100%;
}

/* Logo styling */
.logo {
    display: flex;
    align-items: center;
    flex-shrink: 0;
}

.logo-image {
    height: 80px;
    width: auto;
}

/* Navigation container - takes remaining space */
.main-nav-container {
    display: flex;
    align-items: center;
    flex-grow: 1;
    justify-content: flex-end;
    margin-left: 20px;
}

/* Tab menu container */
.tab-menu-container {
    display: flex;
    align-items: center;
}

/* Tab menu styling */
.tab-menu {
    display: flex;
    list-style: none;
    margin: 0;
    padding: 0;
    align-items: center;
    /* gap: 5px; */
}

.tab-menu li {
    position: relative;
    margin: 0;
}

/* Tab menu links - styled as text with purple border */
.tab-menu > li > a {
    display: block;
    padding: 8px 16px;  
    text-decoration: none;
    font-weight: 500;
    font-size: 14px;
    border-radius: 0;
    transition: all 0.3s ease;
    color: var(--dark-grey);
    white-space: nowrap;
    background-color: var(--white) !important;
    border-bottom: 2px solid var(--purple);
}

/* Ensure all tab classes have consistent white background */
.tab-menu > li > a.tab-home,
.tab-menu > li > a.tab-about,
.tab-menu > li > a.tab-calls,
.tab-menu > li > a.tab-accepted,
.tab-menu > li > a.tab-program,
.tab-menu > li > a.tab-organization,
.tab-menu > li > a.tab-attending,
.tab-menu > li > a.tab-media,
.tab-menu > li > a.tab-important-dates {
    background-color: var(--white) !important;
    color: var(--dark-grey) !important;
}

/* Additional specificity to override any other rules */
header .tab-menu > li > a,
header .tab-menu > li > a.tab-home,
header .tab-menu > li > a.tab-about,
header .tab-menu > li > a.tab-calls,
header .tab-menu > li > a.tab-accepted,
header .tab-menu > li > a.tab-program,
header .tab-menu > li > a.tab-organization,
header .tab-menu > li > a.tab-attending,
header .tab-menu > li > a.tab-media,
header .tab-menu > li > a.tab-important-dates {
    background-color: var(--white) !important;
    background-image: none !important;
    color: var(--dark-grey) !important;
}

/* Active state with cyan border */
.tab-menu > li > a.active {
    border-bottom: 2px solid var(--cyan);
    opacity: 1;
    transform: translateY(0);
}

/* Hover effects */
.tab-menu > li > a:hover {
    opacity: 0.8;
    transform: translateY(-1px);
    background-color: color-mix(in srgb, var(--purple) 20%, transparent);

}

/* Dropdown styling */
.dropdown {
    position: absolute;
    top: 100%;
    left: 0;
    background-color: var(--white);
    border: 1px solid var(--dark-grey);
    border-radius: 4px;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    z-index: 1000;
    min-width: 200px;
    display: none;
    margin-top: 2px;
}

.tab-menu li:hover .dropdown {
    display: block;
    background: var(--white);

    /* background-color: color-mix(in srgb, var(--purple) 20%, transparent); */

}

.dropdown a {
    display: block;
    padding: 10px 15px;
    color: var(--dark-grey);
    text-decoration: none;
    border-bottom: 1px solid var(--dark-grey);
    font-size: 13px;
    background: var(--white);
}

.dropdown a:hover {
    background-color: rgba(138, 43, 226, 0.2);
    color: var(--white);
}

.dropdown a:last-child {
    border-bottom: none;
}

/* Mobile menu toggle */
.mobile-menu-toggle {
    display: none;
    font-size: 24px;
    cursor: pointer;
    color: var(--dark-grey);
    margin-left: 10px;
}

/* Responsive Design */
@media (max-width: 1024px) {
    .header-container {
        padding: 0 15px;
    }
    
    .tab-menu > li > a {
        padding: 6px 12px;
        font-size: 13px;
    }
}

@media (max-width: 768px) {
    .header-container {
        flex-wrap: nowrap;
        padding: 0 10px;
    }
    
    .mobile-menu-toggle {
        display: block;
    }
    
    .main-nav-container {
        position: absolute;
        top: 100%;
        left: 0;
        right: 0;
        background-color: var(--white);
        border-top: 1px solid var(--dark-grey);
        display: none;
        z-index: 999;
    }
    
    .main-nav-container.active {
        display: block;
    }
    
    .tab-menu-container {
        width: 100%;
    }
    
    .tab-menu {
        flex-direction: column;
        width: 100%;
        padding: 10px;
        /* gap: 5px; */
    }
    
    .tab-menu > li > a {
        width: 100%;
        text-align: center;
        padding: 12px;
        margin: 0;
    }
    
    /* Mobile dropdown */
    .dropdown {
        position: static;
        display: none;
        box-shadow: none;
        border: none;
        margin-top: 5px;
        background-color: var(--dark-grey);
    }
    
    .tab-menu li.active .dropdown {
        display: block;
    }
}

@media (max-width: 480px) {
    .logo-image {
        height: 40px;
    }
    
    .header-container {
        padding: 0 5px;
    }
}