/* 
    Lumbini Technological University (LTU) Conference Website Styles
    Primary: #1E3A5F (Deep Blue)
    Accent: #D32F2F (Red)
*/

@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700&display=swap');

:root {
    --ltu-primary: #1E3A5F;
    --ltu-accent: #D32F2F;
    --ltu-bg-light: #F8F9FA;
    --ltu-text-dark: #333333;
    --ltu-text-light: #FFFFFF;
}

.text-accent {
    color: var(--ltu-accent) !important;
}

/* Global / Utility */
html {
    scroll-behavior: smooth;
    scroll-padding-top: 125px; /* Account for redesigned fixed topbar + navbar */
}
body {
    font-family: 'Inter', sans-serif;
    color: var(--ltu-text-dark);
    background-color: var(--ltu-bg-light);
}

main {
    padding-top: 130px; /* Unified offset for fixed topbar + navbar (Desktop) */
}

@media (max-width: 991px) {
    main {
        padding-top: 70px; /* Further reduced for mobile to eliminate gap */
    }
}

a {
    transition: color 0.3s ease;
}

/* Topbar */
.ltu-topbar {
    background-color: #142842; /* Darker than primary */
    color: #cbd5e1;
    font-size: 0.85rem;
    padding: 6px 0;
}
.ltu-topbar-text {
    letter-spacing: 0.02em;
}
.ltu-topbar-text strong {
    color: #ffffff;
    font-weight: 600;
}
.ltu-topbar-divider {
    color: rgba(255,255,255,0.2);
    margin: 0 10px;
}

/* Navbar */
.ltu-navbar {
    background-color: var(--ltu-primary) !important;
    box-shadow: 0 4px 6px rgba(0,0,0,0.1);
}
.ltu-navbar .navbar-brand {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 0;
}
.brand-logo {
    height: 50px;
    background: #fff;
    border-radius: 50%;
    padding: 2px;
    box-shadow: 0 0 10px rgba(255,255,255,0.1);
}
.brand-text {
    display: flex;
    flex-direction: column;
    line-height: 1.1;
}
.brand-title {
    font-size: 1.3rem;
    font-weight: 800;
    color: #fff;
    letter-spacing: 0.5px;
}
.brand-subtitle {
    font-size: 0.7rem;
    color: rgba(255,255,255,0.8);
    text-transform: uppercase;
    font-weight: 500;
}
.ltu-navbar .nav-link {
    color: rgba(255, 255, 255, 0.85) !important;
    text-transform: uppercase;
    font-size: 0.82rem;
    font-weight: 600;
    padding: 0.5rem 0.8rem !important;
    letter-spacing: 0.5px;
    position: relative;
    transition: all 0.3s ease;
}
.ltu-navbar .nav-link:hover,
.ltu-navbar .nav-link.active {
    color: #fff !important;
}
.ltu-navbar .nav-link:not(.nav-cta-fill):not(.nav-cta-outline):not(.admin-pill)::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 50%;
    width: 0;
    height: 2px;
    background-color: var(--ltu-accent);
    transition: all 0.3s ease;
    transform: translateX(-50%);
}
.ltu-navbar .nav-link:hover::after,
.ltu-navbar .nav-link.active::after {
    width: 60%;
}

/* Main Submission CTA with Pulse Effect */
.ltu-submission-pulse {
    background: linear-gradient(135deg, #f59e0b 0%, #d97706 100%) !important;
    color: #fff !important;
    border-radius: 50px;
    padding: 0.6rem 1.5rem !important;
    font-weight: 800 !important;
    font-size: 0.85rem !important;
    letter-spacing: 1px !important;
    box-shadow: 0 0 0 0 rgba(245, 158, 11, 0.7);
    animation: ltu-pulse-amber 2s infinite;
    transition: all 0.3s ease !important;
    border: none !important;
}
.ltu-submission-pulse:hover {
    transform: scale(1.05) translateY(-2px);
    box-shadow: 0 10px 20px rgba(0,0,0,0.2);
    animation: none;
    background: #fbbf24 !important;
    color: #1e3a5f !important;
}
.ltu-submission-pulse::after {
    display: none !important; /* Remove the underline */
}

@keyframes ltu-pulse-amber {
    0% {
        transform: scale(0.98);
        box-shadow: 0 0 0 0 rgba(245, 158, 11, 0.7);
    }
    70% {
        transform: scale(1.05);
        box-shadow: 0 0 0 15px rgba(245, 158, 11, 0);
    }
    100% {
        transform: scale(0.98);
        box-shadow: 0 0 0 0 rgba(245, 158, 11, 0);
    }
}

.nav-cta-outline {
    border: 1.5px solid rgba(255,255,255,0.4);
    border-radius: 50px;
    padding: 0.5rem 1.2rem !important;
    margin-top: 2px;
}
.nav-cta-outline:hover, .nav-cta-outline.active {
    background: rgba(255,255,255,0.1);
    border-color: #fff;
}
.nav-cta-fill {
    background: var(--ltu-accent);
    color: #fff !important;
    border-radius: 50px;
    padding: 0.5rem 1.2rem !important;
    box-shadow: 0 4px 10px rgba(211, 47, 47, 0.3);
    margin-top: 2px;
}
.nav-cta-fill:hover {
    background: #a82525 !important;
    transform: translateY(-1px);
    box-shadow: 0 6px 15px rgba(211, 47, 47, 0.4);
}
.admin-pill {
    background: #f59e0b;
    color: #1e3a5f !important;
    border-radius: 50px;
    padding: 0.5rem 1.2rem !important;
    font-weight: 700 !important;
}
.admin-pill:hover {
    background: #fbbf24 !important;
}

/* Hero Carousel */
.ltu-hero-section {
    position: relative;
    /* margin-top: 116px; - Removed, handled by global main padding */
}
.ltu-carousel-overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(30, 58, 95, 0.7); /* Deep blue overlay */
    z-index: 1;
}
.ltu-hero-item {
    height: 85vh;
    min-height: 500px;
    background-size: cover;
    background-position: center;
    display: flex;
    align-items: center;
}
.ltu-hero-caption {
    z-index: 2;
    position: relative;
    height: 100%;
    display: flex;
    flex-direction: column;
    justify-content: center;
}
.ltu-hero-caption h1 {
    font-size: 3.5rem;
    font-weight: 700;
    margin-bottom: 1rem;
    text-shadow: 2px 2px 4px rgba(0,0,0,0.5);
}
.ltu-hero-caption p {
    font-size: 1.25rem;
    margin-bottom: 2rem;
}

/* Countdown */
.ltu-countdown-section {
    background-color: #142842;
    color: var(--ltu-text-light);
    padding: 3rem 0;
    position: relative;
    box-shadow: 0 -4px 10px rgba(0,0,0,0.1);
    z-index: 10;
}
.ltu-countdown-item {
    text-align: center;
    padding: 1.5rem;
    background: rgba(255,255,255,0.05);
    border-radius: 8px;
    margin: 0.5rem;
    border: 1px solid rgba(255,255,255,0.1);
}
.ltu-countdown-number {
    font-size: 3rem;
    font-weight: 700;
    color: var(--ltu-accent);
    line-height: 1;
    margin-bottom: 0.5rem;
}
.ltu-countdown-label {
    text-transform: uppercase;
    font-size: 0.85rem;
    letter-spacing: 2px;
    opacity: 0.8;
}

/* About & Generic Sections */
.ltu-section {
    padding: 6rem 0;
}
.ltu-section-bg-white {
    background-color: #FFFFFF;
}
.ltu-section-bg-light {
    background-color: var(--ltu-bg-light);
}
.ltu-section-title {
    color: var(--ltu-primary);
    font-weight: 700;
    margin-bottom: 3rem;
    position: relative;
    padding-bottom: 1rem;
    text-transform: uppercase;
    letter-spacing: 1px;
}
.ltu-section-title::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 50%;
    transform: translateX(-50%);
    width: 80px;
    height: 4px;
    background-color: var(--ltu-accent);
    border-radius: 2px;
}
.ltu-section-title.text-start::after {
    left: 0;
    transform: none;
}

/* Call for Papers & Guidelines */
.ltu-info-card {
    background: #fff;
    padding: 2rem;
    border-radius: 8px;
    box-shadow: 0 4px 15px rgba(0,0,0,0.05);
    height: 100%;
}
.ltu-topic-list, .ltu-guideline-list {
    list-style: none;
    padding: 0;
}
.ltu-topic-list li, .ltu-guideline-list li {
    padding: 0.75rem 0;
    border-bottom: 1px dashed #dee2e6;
    position: relative;
    padding-left: 2rem;
    font-size: 1.05rem;
}
.ltu-topic-list li:last-child, .ltu-guideline-list li:last-child {
    border-bottom: none;
}
.ltu-topic-list li::before, .ltu-guideline-list li::before {
    /* Check/Arrow icon from bootstrap icons or pure CSS */
    content: "→";
    color: var(--ltu-accent);
    position: absolute;
    left: 0;
    font-weight: bold;
    font-size: 1.2rem;
}

/* Schedule Tabs */
.ltu-schedule-tabs {
    justify-content: center;
    border-bottom: 2px solid #e2e8f0;
    margin-bottom: 3rem;
}
.ltu-schedule-tabs .nav-link {
    color: #475569;
    font-weight: 600;
    font-size: 1.05rem;
    border-radius: 8px 8px 0 0;
    border: none;
    padding: 0.8rem 2.5rem;
    margin: 0 0.25rem;
    transition: all 0.3s ease;
}
.ltu-schedule-tabs .nav-link:hover {
    color: var(--ltu-primary);
    background-color: #f1f5f9;
}
.ltu-schedule-tabs .nav-link.active {
    background: #fff;
    color: var(--ltu-primary);
    border-bottom: 3px solid #162d4a;
}

/* Schedule Card Redesign */
.ltu-schedule-card {
    background: #fff;
    border-radius: 12px;
    box-shadow: 0 10px 30px rgba(0,0,0,0.06);
    border-left: 6px solid #162d4a; /* Primary accent border */
    padding: 2rem;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    position: relative;
    overflow: hidden;
}
.ltu-schedule-card:hover {
    transform: translateY(-8px);
    box-shadow: 0 15px 40px rgba(0,0,0,0.12);
}

/* Time Column */
.ltu-schedule-time-col {
    min-width: 120px;
}
.ltu-schedule-time-box {
    display: flex;
    flex-direction: column;
    align-items: center;
    color: #b71c1c; /* Requested red color */
}
.ltu-schedule-time-box i {
    font-size: 1.4rem;
    opacity: 1;
}
.ltu-schedule-time-box .time-start, 
.ltu-schedule-time-box .time-end {
    font-weight: 700;
    font-size: 1rem;
}
.ltu-schedule-time-box .time-divider {
    width: 2px;
    height: 15px;
    background: rgba(183, 28, 28, 0.2);
    margin: 4px 0;
}

/* Content Column */
.ltu-schedule-title {
    color: #162d4a;
    letter-spacing: -0.5px;
}
.ltu-schedule-speakers-list {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
    line-height: 1.4;
}
.ltu-schedule-speaker-item .speaker-name {
    color: #334155;
    font-size: 1.05rem;
}
.ltu-schedule-speaker-item .speaker-meta {
    font-size: 0.85rem;
    color: #b71c1c; /* Requested red color */
    opacity: 0.9;
}
.ltu-schedule-desc {
    font-size: 0.92rem;
    line-height: 1.6;
}

/* Avatar Stack */
.ltu-avatar-stack {
    margin-left: 20px;
}
.ltu-speaker-avatar-container {
    margin-left: -18px; /* Overlap */
    transition: all 0.3s ease;
    z-index: 1;
}
.ltu-speaker-avatar-container:hover {
    z-index: 10;
    transform: scale(1.2) translateY(-5px);
}
.ltu-speaker-avatar-sm {
    width: 60px;
    height: 60px;
    border-radius: 50%;
    object-fit: cover;
    border: 3px solid #fff;
    box-shadow: 0 4px 12px rgba(0,0,0,0.15);
    cursor: pointer;
}

/* Avatar Tooltip */
.ltu-avatar-tooltip {
    position: absolute;
    bottom: 100%;
    left: 50%;
    transform: translateX(-50%) translateY(-15px);
    background: rgba(15, 23, 42, 0.95);
    color: #fff;
    padding: 8px 15px;
    border-radius: 6px;
    font-size: 0.8rem;
    text-align: center;
    white-space: nowrap;
    opacity: 0;
    visibility: hidden;
    transition: all 0.3s ease;
    pointer-events: none;
    box-shadow: 0 8px 20px rgba(0,0,0,0.25);
    line-height: 1.4;
}
.ltu-avatar-tooltip::after {
    content: "";
    position: absolute;
    top: 100%;
    left: 50%;
    margin-left: -8px;
    border-width: 8px;
    border-style: solid;
    border-color: rgba(15, 23, 42, 0.95) transparent transparent transparent;
}
.ltu-speaker-avatar-container:hover .ltu-avatar-tooltip {
    opacity: 1;
    visibility: visible;
    transform: translateX(-50%) translateY(-10px);
}

/* Responsive Stacking */
@media (max-width: 991px) {
    .ltu-schedule-card {
        flex-direction: column;
        text-align: center;
        padding-top: 3rem;
    }
    .ltu-schedule-time-col {
        margin-bottom: 1.5rem;
        width: 100%;
    }
    .ltu-schedule-time-box {
        flex-direction: row;
        justify-content: center;
        gap: 15px;
        align-items: center;
    }
    .ltu-schedule-time-box .time-divider {
        width: 15px;
        height: 2px;
        margin: 0;
    }
    .ltu-schedule-main-col {
        padding: 0 !important;
        margin-bottom: 2rem;
    }
    .ltu-schedule-speakers-list {
        justify-content: center;
    }
    .ltu-schedule-avatar-col {
        margin: 0 auto !important;
    }
    .ltu-avatar-stack {
        margin-left: 18px; /* Offset the first avatar's negative margin */
    }
}

/* Speakers */
.ltu-speaker-card {
    background: #fff;
    border-radius: 12px;
    overflow: hidden;
    box-shadow: 0 4px 15px rgba(0,0,0,0.06);
    text-align: center;
    transition: all 0.3s ease;
    height: 100%;
    border: 1px solid #f0f0f0;
}
.ltu-speaker-card:hover {
    box-shadow: 0 12px 30px rgba(0,0,0,0.12);
    transform: translateY(-8px);
}
.ltu-speaker-img {
    width: 100%;
    height: 280px;
    object-fit: cover;
}
.ltu-speaker-info {
    padding: 2rem 1.5rem;
}
.ltu-speaker-name {
    color: var(--ltu-primary);
    font-weight: 700;
    margin-bottom: 0.5rem;
    font-size: 1.25rem;
}
.ltu-speaker-designation {
    color: var(--ltu-accent);
    font-size: 0.95rem;
    margin-bottom: 1.5rem;
    font-weight: 500;
}

/* Modal adjustments */
.ltu-modal-header {
    background-color: var(--ltu-primary);
    color: #fff;
    border-bottom: none;
}
.ltu-modal-header .btn-close {
    filter: invert(1);
}

/* Buttons */
.ltu-btn-primary {
    background-color: var(--ltu-primary);
    color: #fff;
    border: none;
    padding: 12px 30px;
    border-radius: 6px;
    font-weight: 600;
    transition: all 0.3s ease;
    display: inline-block;
    text-decoration: none;
}
.ltu-btn-primary:hover {
    background-color: #142842;
    color: #fff;
    transform: translateY(-2px);
    box-shadow: 0 4px 10px rgba(30, 58, 95, 0.3);
}
.ltu-btn-accent {
    background-color: var(--ltu-accent);
    color: #fff;
    border: none;
    padding: 12px 30px;
    border-radius: 6px;
    font-weight: 600;
    transition: all 0.3s ease;
    display: inline-block;
    text-decoration: none;
}
.ltu-btn-accent:hover {
    background-color: #a82525;
    color: #fff;
    transform: translateY(-2px);
    box-shadow: 0 4px 10px rgba(211, 47, 47, 0.3);
}
.ltu-btn-outline {
    background-color: transparent;
    color: var(--ltu-text-light);
    border: 2px solid var(--ltu-text-light);
    padding: 10px 30px;
    border-radius: 6px;
    font-weight: 600;
    transition: all 0.3s ease;
    display: inline-block;
    text-decoration: none;
}
.ltu-btn-outline:hover {
    background-color: var(--ltu-text-light);
    color: var(--ltu-primary);
    transform: translateY(-2px);
}

/* Registration Form */
.ltu-registration-box {
    background: #fff;
    border-radius: 12px;
    box-shadow: 0 10px 30px rgba(0,0,0,0.08);
    overflow: hidden;
}
.ltu-reg-info {
    background-color: var(--ltu-primary);
    color: #fff;
    padding: 3rem;
    height: 100%;
}
.ltu-reg-info h3 {
    font-weight: 700;
    margin-bottom: 1.5rem;
}
.ltu-price-table {
    width: 100%;
    margin-top: 2rem;
}
.ltu-price-table th, .ltu-price-table td {
    padding: 1rem 0;
    border-bottom: 1px solid rgba(255,255,255,0.1);
}
.ltu-price-amount {
    color: var(--ltu-accent);
    font-weight: 700;
    font-size: 1.25rem;
}
.ltu-reg-form-container {
    padding: 3rem;
}
.ltu-form-label {
    font-weight: 500;
    color: var(--ltu-primary);
    margin-bottom: 0.5rem;
}
.ltu-form-control {
    border: 1px solid #ced4da;
    border-radius: 6px;
    padding: 0.75rem 1rem;
    background-color: #f8f9fa;
}
.ltu-form-control:focus {
    background-color: #fff;
    border-color: var(--ltu-primary);
    box-shadow: 0 0 0 0.25rem rgba(30, 58, 95, 0.2);
}

/* Sponsors */
.ltu-sponsors-grid {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 3rem;
    align-items: center;
}
.ltu-sponsor-item {
    text-align: center;
    padding: 1rem;
}
.ltu-sponsor-logo {
    max-width: 180px;
    height: auto;
    filter: grayscale(100%);
    opacity: 0.6;
    transition: all 0.3s ease;
}
.ltu-sponsor-item:hover .ltu-sponsor-logo {
    filter: grayscale(0%);
    opacity: 1;
    transform: scale(1.05);
}

/* Map */
.ltu-contact-info {
    background: #fff;
    padding: 2.5rem;
    border-radius: 8px;
    box-shadow: 0 4px 15px rgba(0,0,0,0.05);
    height: 100%;
}
.ltu-contact-item {
    display: flex;
    align-items: flex-start;
    margin-bottom: 1.5rem;
}
.ltu-contact-icon {
    font-size: 1.5rem;
    color: var(--ltu-accent);
    margin-right: 15px;
    margin-top: 2px;
}
.ltu-map-container {
    border-radius: 8px;
    overflow: hidden;
    box-shadow: 0 4px 15px rgba(0,0,0,0.1);
    height: 100%;
    min-height: 400px;
}

/* Footer */
.ltu-footer {
    background-color: #0b1a2e; /* Very Dark Blue */
    color: #b0bec5;
    padding: 5rem 0 2rem;
    border-top: 5px solid var(--ltu-accent);
}
.ltu-footer-brand {
    color: #fff;
    font-weight: 700;
    font-size: 1.5rem;
    margin-bottom: 1rem;
    display: block;
}
.ltu-footer-title {
    color: #fff;
    font-weight: 700;
    margin-bottom: 1.5rem;
    text-transform: uppercase;
    font-size: 1.1rem;
    letter-spacing: 1px;
}
.ltu-footer-links {
    list-style: none;
    padding: 0;
}
.ltu-footer-links li {
    margin-bottom: 0.75rem;
}
.ltu-footer a {
    color: #b0bec5;
    text-decoration: none;
    transition: color 0.3s ease;
}
.ltu-footer a:hover {
    color: var(--ltu-accent);
    padding-left: 5px;
}
.ltu-social-icons {
    display: flex;
    gap: 10px;
    margin-top: 1.5rem;
}
.ltu-social-icon {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
    background-color: rgba(255,255,255,0.05);
    border-radius: 50%;
    color: #fff;
    transition: all 0.3s ease;
}
.ltu-social-icon:hover {
    background-color: var(--ltu-accent);
    color: #fff;
    transform: translateY(-3px);
}
.ltu-footer-bottom {
    margin-top: 3.5rem;
    padding-top: 2rem;
    border-top: 1px solid rgba(255,255,255,0.1);
    text-align: center;
    font-size: 0.9rem;
}

/* Back to Top */
#ltu-back-to-top {
    position: fixed;
    bottom: 40px;
    right: 40px;
    width: 50px;
    height: 50px;
    background-color: var(--ltu-accent);
    color: #fff;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.3rem;
    cursor: pointer;
    opacity: 0;
    visibility: hidden;
    transition: all 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.275);
    z-index: 999;
    box-shadow: 0 8px 20px rgba(211, 47, 47, 0.3);
    text-decoration: none;
}

#ltu-back-to-top.show {
    opacity: 1;
    visibility: visible;
}

#ltu-back-to-top:hover {
    background-color: var(--ltu-primary);
    transform: translateY(-8px) scale(1.15);
    box-shadow: 0 12px 30px rgba(30, 58, 95, 0.4);
    color: #fff;
}

@media (max-width: 767px) {
    #ltu-back-to-top {
        bottom: 25px;
        right: 25px;
        width: 44px;
        height: 44px;
        font-size: 1.1rem;
    }
}

/* Old ltu-schedule-card removed - now centrally managed */

/* Responsive specific adjustments */
@media (max-width: 991px) {
    .ltu-schedule-card {
        flex-direction: column;
        align-items: flex-start;
    }
    .ltu-schedule-time {
        margin-bottom: 1rem;
    }
    .ltu-hero-caption h1 {
        font-size: 2.5rem;
    }
}
@media (max-width: 767px) {
    .ltu-hero-item {
        height: auto;
        aspect-ratio: 16 / 9;
        min-height: 300px;
        background-size: contain;
        background-repeat: no-repeat;
        background-color: #1a202c; /* Solid background if image doesn't fill */
    }
    .ltu-hero-caption h1 {
        font-size: 1.75rem;
    }
    .ltu-hero-caption p {
        font-size: 1rem;
        margin-bottom: 1.5rem;
    }
    .ltu-section {
        padding: 4rem 0;
    }
    .ltu-countdown-item {
        margin-bottom: 1rem;
    }
}
/* Crucial Deadlines */
.ltu-deadlines-section {
    margin-top: -50px;
    position: relative;
    z-index: 20;
}
.ltu-deadlines-card {
    background-color: var(--ltu-primary);
    border-radius: 15px;
    padding: 2.5rem;
    box-shadow: 0 10px 30px rgba(0,0,0,0.15);
    color: #fff;
    text-align: center;
}
.ltu-deadlines-title {
    font-size: 1.75rem;
    font-weight: 700;
    margin-bottom: 2rem;
}
.ltu-deadline-item {
    padding: 0 1rem;
    position: relative;
}
.ltu-deadline-item:not(:last-child)::after {
    content: "";
    position: absolute;
    right: 0;
    top: 50%;
    transform: translateY(-50%);
    height: 60%;
    width: 1px;
    background-color: rgba(255,255,255,0.2);
}
.ltu-deadline-label {
    display: block;
    font-size: 0.7rem;
    text-transform: uppercase;
    letter-spacing: 1px;
    margin-bottom: 0.5rem;
    opacity: 0.8;
}
.ltu-deadline-date {
    display: block;
    font-size: 1.25rem;
    font-weight: 700;
}
.ltu-deadline-date.text-accent {
    color: #ff4d4d !important; /* Specific red for dark bg */
}

@media (max-width: 767px) {
    .ltu-deadlines-section { margin-top: 0; padding: 2rem 0; }
    .ltu-deadline-item { margin-bottom: 1.5rem; padding-bottom: 1.5rem; border-bottom: 1px solid rgba(255,255,255,0.1); }
    .ltu-deadline-item::after { display: none; }
}