* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: Arial, Helvetica, sans-serif;
}

body {
    font-family: 'Segoe UI', system-ui, -apple-system, sans-serif;
    background-color: #ffffff;
    color: #333333;
    margin: 0;
}

header {
    max-width: 1500px;
    margin: auto 0;
}

.icon-span svg {
    width: 30px;
    height: 30px;
}

.dateLocal {
    display: flex;
    align-items: center;
    gap: 5px;
}

nav {
    position: fixed;
    width: 100%;
    background: #1F3B8A;
    z-index: 100;
}

.nav-inner {
    max-width: 1500px;
    margin: 0 auto;
    padding: 15px 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    color: #fff;
}

menu {
    display: flex;
    gap: 30px;
}

menu a {
    color: #fff;
    text-decoration: none;
    font-weight: 500;
}

menu a:hover {
    text-decoration: none;
}

menu a:hover {
    text-decoration: none;
    color: #009966;
}

.registerBtn {
    background-color: #009966;
    padding: 10px 22px;
    border-radius: 8px;
    color: #fff;
    text-decoration: none;
    font-weight: 600;
}

.registerBtn:hover {
    background-color: #00b377;
}

main {
    padding-top: 30px;
}

.section-1 {
    background-image: url("../imgs/image.png");
    background-repeat: no-repeat;
    background-position: center;
    background-size: cover;
    min-height: 100vh;
    color: #fff;
    min-height: 700px;
}

.cover {
    background: rgba(0, 0, 0, 0.65);
    min-height: 700px;
    display: flex;
    justify-content: center;
}

.cover-inner {
    max-width: 1500px;
    width: 100%;
    padding: 80px 20px;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 30px;
    text-align: center;
}

.artic-1 {
    display: flex;
    flex-direction: column;
}

.title {
    font-size: 48px;
    font-weight: 700;
    line-height: 1.2;
    margin-bottom: 15px;
}

.cover p {
    font-size: 18px;
    opacity: 0.9;
}


.boxes {
    display: flex;
    flex-wrap: wrap;
    gap: 20px;
    justify-content: center;
    width: 100%;
    margin-top: 30px;
}

.box {
    background: rgba(255, 255, 255, 0.15);
    border: 1px solid rgba(255, 255, 255, 0.25);
    padding: 20px 25px;
    border-radius: 12px;
    backdrop-filter: blur(6px);
    width: calc((100% - (20px * 3)) / 4); 
    min-width: 200px; 
    box-sizing: border-box;
    text-align: center;
}

.box:hover {
    background: rgba(255, 255, 255, 0.20);
}

.box span {
    display: block;
    font-weight: 700;
    font-size: 14px;
    margin-bottom: 8px;
    color: #00ffb3;
}

.box p {
    font-size: 16px;
}

.menuBtn {
    display: none;
}

.section-2 {
    width: 100%;
    margin: auto;
    background-color: #F9FAFB;
}

.sec2-inner {
    max-width: 1500px;
    margin: auto;
    padding: 70px;
}

.sec2-title {
    font-size: 30px;
    font-weight: 300;
    color: #1C398E;
    padding-bottom: 50px;
}

.section-2 p {
    color: #535353;
    font-size: 20px;
    font-weight: 200;
}

.sec2-div {
    background-color: #ECFDF5;
    color: #535353;
    font-size: 20px;
    font-weight: 200;
    padding: 20px;
    margin: 20px 0;
    border-radius: 3px;
    border-left: 4px solid #009966;
}

.sec2-div span {
    color: #004F3B;
    font-weight: bold;
}

.key-topics {
    max-width: 1200px;
    margin: 100px auto;
    padding: 0 20px;
}

.key-topics h2{
    font-size: 36px;
    color: #163a9f;
    margin-bottom: 70px;
}

.topics-wrapper {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
    align-items: center;
}


.topics-media video {
    width: 100%;
    border-radius: 24px;
    object-fit: cover;
}

.topics-content h2 {
    font-size: 48px;
    line-height: 1.1;
    margin-bottom: 30px;
}

.topics-content .blue {
    color: #1f3b8a;
}

.topics-content .orange {
    color: #f5b14c;
}

.topics-lists {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 30px;
}

.topics-lists ul {
    list-style: none;
    padding: 0;
}

.topics-lists li {
    font-size: 16px;
    color: #1f3b8a;
    margin-bottom: 12px;
    position: relative;
    padding-left: 18px;
}

.topics-lists li::before {
    content: "•";
    position: absolute;
    left: 0;
    color: #1f3b8a;
    font-size: 22px;
    line-height: 1;
}


.sec-4 {
    background-color: #F9FAFB;
    width: 100%;
}

.speakers {
    max-width: 1200px;
    margin: 120px auto;
    padding: 80px 20px;
    text-align: center;
}

.speakers h2 {
    font-size: 36px;
    color: #163a9f;
    margin-bottom: 70px;
}

.speakers-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr); 
    row-gap: 90px;
    column-gap: 60px;
}

.speaker {
    display: flex;
    flex-direction: column;
    align-items: center;
}

.avatar {
    width: 200px;
    height: 200px;
    border-radius: 50%;
    padding: 4px;
    background: #c9f5de;
    margin-bottom: 20px;
}

.avatar img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    border-radius: 50%;
}

.speaker h3 {
    font-size: 20px;
    color: #000;
    margin-bottom: 6px;
}

.speaker p {
    font-size: 16px;
    color: #6b7280;
    font-style: italic;
}

.registration {
    min-height: 400px;
    background: linear-gradient(90deg, #1e3a8a, #064e3b);
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 60px 20px;
}

.registration-inner {
    width: 100%;
    max-width: 1200px;
    text-align: center;
    color: #fff;
}

.registration h2 {
    font-size: 42px;
    margin-bottom: 40px;
}

.reg-card {
    max-width: 900px;
    margin: 0 auto;
    padding: 50px 30px;
    background: rgba(255, 255, 255, 0.12);
    border: 2px solid rgba(255, 255, 255, 0.35);
    border-radius: 14px;
    backdrop-filter: blur(6px);
}

.reg-card h3 {
    font-size: 26px;
    font-weight: 700;
    margin-bottom: 20px;
}

.reg-card p {
    font-size: 18px;
    line-height: 1.6;
    margin-bottom: 35px;
}

.reg-card a {
    color: #ffffff;
    font-weight: 600;
    text-decoration: underline;
}

.reg-btn {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
    text-decoration: none;
    background: #16a34a;
    padding: 14px 30px;
    border-radius: 10px;
    color: #fff;
    font-size: 18px;
}

.reg-btn:hover {
    background: #22c55e;
}

.container {
    max-width: 1500px;
    margin: 0 auto;
    margin-bottom: 50px;
}

.main-title {
    font-size: 36px;
    color: #163a9f;
    margin-bottom: 70px;
    text-align: center;
}

.cards-wrapper {
    padding: 0 30px;
    display: flex;
    flex-direction: row;
    gap: 25px;
    align-items: stretch;
    justify-content: center;
}

.cards-wrapper h2 {
    font-weight: 400;
    font-size: 12px;
}

.card {
    flex: 1;
    border-radius: 12px;
    padding: 30px;
    display: flex;
    flex-direction: column;
}

.card-blue {
    border: 2px solid #c2d4f0;
}

.card-blue h2 {
    color: #1e4b96;
}

.card-green {
    width: 100%;
    border: 2px solid #b3e6d5;
}

.card-green h2 {
    color: #009966;
}

.card-header {
    display: flex;
    align-items: center;
    gap: 12px;
    margin-bottom: 20px;
}

.card-header h2 {
    font-size: 1.25rem;
    margin: 0;
}

.card-content {
    flex-grow: 1;
    margin-bottom: 25px;
}

.card-content p {
    margin: 0 0 15px 0;
}

.card-content ul{
    list-style: none;
    padding: 0;
}

.card-content a{
    text-decoration: none;
    color: #007bff;
    font-weight: bold;
    line-height: 1.6;
}

.card-content a:hover{
    color:green;
    text-decoration: underline;
}

.highlight-green {
    color: #009966;
    font-weight: bold;
}

.info-group {
    margin-bottom: 15px;
}

.info-group label {
    display: block;
    color: #555555;
    font-size: 0.95rem;
    margin-bottom: 4px;
}

.email-link {
    color: #007bff;
    text-decoration: none;
    font-size: 1.1rem;
}

.btn {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    padding: 14px;
    border-radius: 8px;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    text-decoration: none;
    transition: background-color 0.2s ease;
    width: 100%;
}

.btn-outline {
    border: 1px solid #c2d4f0;
    color: #1e4b96;
    background: #ffffff;
}

.btn-outline:hover {
    background-color: #f0f4fb;
}

.btn-solid-green {
    background-color: #009966;
    color: #ffffff;
    border: none;
}

.btn-solid-green:hover {
    background-color: #007a52;
}

.file {
    color: #162a85;
}

.icon {
    font-size: 1.2rem;
    color: #007a52;
}

.logistics-wrapper {
    display: flex;
    flex-direction: column;
    gap: 30px;
    padding: 20px;
    align-items: stretch;
    justify-content: center;
}

.logistics-card {
    border: 1px solid #c2d4f0;
    border-radius: 12px;
    padding: 25px;
    background-color: #ffffff;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.02);
}

.blue-text {
    color: #1e4b96;
}

.full-width {
    width: 100%;
    display: flex;
    justify-content: center;
    box-sizing: border-box;
}

.logistics-card label {
    color: #666;
    font-size: 0.9rem;
    margin-bottom: 2px;
    display: block;
}

.logistics-card p {
    margin-top: 5px;
    margin-bottom: 15px;
}

.blue-icon {
    color: #1e4b96;
    font-weight: bold;
}

.logistics-card .btn-outline {
    border: 1px solid #c2d4f0;
    background: #ffffff;
    color: #1e4b96;
    padding: 10px;
    font-weight: 500;
    transition: all 0.2s ease;
}

.logistics-card .btn-outline:hover {
    background-color: #f8faff;
    border-color: #1e4b96;
}

.main-title1 {
    padding-top: 50px;
}

.logistics-container {
    max-width: 1500px;
    margin: 40px auto;
    padding: 0 20px;
}

.section-title {
    text-align: center;
    color: #1e4b96;
    margin-bottom: 30px;
}

.logistics-card {
    border: 1px solid #c2d4f0;
    border-radius: 12px;
    padding: 25px;
    background: #fff;
    width: 100%;
    display: flex;
    flex-direction: column;

}

.logistics-card .card-header {
    display: flex;
    align-items: center;
    gap: 10px;
    color: #1e4b96;
    margin-bottom: 15px;
}

.logistics-card h3 {
    margin: 0;
    font-size: 1.15rem;
}

.info-block {
    margin-bottom: 15px;
}

.info-block label {
    display: block;
    font-size: 0.9rem;
    color: #666;
    margin-bottom: 4px;
}

.btn-outline-wide {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 10px;
    width: 100%;
    padding: 12px;
    border: 1px solid #c2d4f0;
    border-radius: 8px;
    color: #1e4b96;
    text-decoration: none;
    font-weight: 500;
    transition: background 0.2s;
}

.btn-outline-wide:hover {
    background: #f0f5ff;
}

.main-footer {
    background-color: #162a85;
    color: #ffffff;
    padding: 60px 20px 30px;
    margin-top: 60px;
}

.footer-content {
    max-width: 1500px;
    width: 94%;
    margin: 0 auto;
    display: flex;
    justify-content: space-between;
    gap: 40px;
    flex-wrap: wrap;
}

.footer-column {
    flex: 1;
    min-width: 250px;
}

.footer-column h4 {
    font-size: 1.2rem;
    margin-bottom: 20px;
    display: flex;
    align-items: center;
    gap: 10px;
}

.footer-column a {
    margin: 8px 0;
    font-size: 0.95rem;
    opacity: 0.9;
    color: #fff;
    display: block;
    text-decoration: none;
}

.sec-5 {
    width: 100%;
    background-color: #F9FAFB;
}

.footer-bottom {
    max-width: 1500px;
    margin: 40px auto 0;
    padding-top: 20px;
    border-top: 1px solid rgba(255, 255, 255, 0.2);
    text-align: center;
    font-size: 0.9rem;
    opacity: 0.8;
}

.committees-wrapper {
    display: flex;
    flex-direction: column;
    gap: 15px;
    max-width: 1500px;
    margin: 0 auto;
}

.committee-item {
    border: 1px solid #e0e6ed;
    border-radius: 12px;
    background-color: #ffffff;
    overflow: hidden;
    transition: all 0.3s ease;
    width: 94%;
    margin: auto;
}

.committee-item summary {
    padding: 20px 25px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    cursor: pointer;
    list-style: none;
}

.committee-item summary::-webkit-details-marker {
    display: none;
}

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

.summary-content h3 {
    margin: 0;
    color: #1e4b96;
    font-size: 1.1rem;
    font-weight: 600;
}

.chevron {
    width: 10px;
    height: 10px;
    border-right: 2px solid #99a1b3;
    border-bottom: 2px solid #99a1b3;
    transform: rotate(45deg);
    transition: transform 0.3s ease;
}

.committee-item[open] .chevron {
    transform: rotate(-135deg);
}

.details-content {
    padding: 0 25px 25px 60px;
}

.details-content ul {
    list-style: none;
    padding: 0;
    margin: 0;
}

.details-content li {
    position: relative;
    padding-bottom: 10px;
    color: #4a5568;
    font-size: 1rem;
    line-height: 1.6;
}

.dateLine {
    display: flex;
    align-items: center;
}

.details-content li::before {
    content: "•";
    position: absolute;
    left: -20px;
    color: #4a5568;
}

.committee-item:hover {
    border-color: #c2d4f0;
    box-shadow: 0 4px 12px rgba(30, 75, 150, 0.05);
}

.slesh {
    display: inline;
}

.video-box {
    position: relative;
    border-radius: 24px;
    overflow: hidden;
}

.video-box video {
    width: 100%;
    display: block;
}

.play-btn {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 90px;
    height: 90px;
    border-radius: 50%;
    background: rgba(0, 0, 0, 0.5);
    color: #fff;
    font-size: 48px;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: 0.3s;
}

.play-btn:hover {
    transform: translate(-50%, -50%) scale(1.1);
}

.pdf-link{
    color: #007bff;
    text-decoration: none;
    display: flex;
    justify-content: center;
}

.history-img{
    width: 80%;
    margin: 0 10%;
}

#topics,
#speakers,
#registration,
#footer {
    scroll-margin-top: 90px;
}

.conf-section {
    background: #1F3B8A;
    padding: 100px 20px;
}

.conf-wrapper {
    max-width: 1400px;
    margin: auto;
    display: flex;
    justify-content: space-between;
    align-items: flex-end;
    gap: 20px;
}

.conf-item {
    flex: 1;
    text-align: center;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 30px;
}

.conf-item.center {
    flex: 1.5;
}

.conf-item img {
    width: 100%;
    height: auto;
    object-fit: cover;
    border-radius: 8px;
}

.conf-title {
    color: #fff;
    font-size: 42px;
}

.conf-title span {
    color: #00FFB3;
}

.highlight {
    color: #00FFB3;
}

@media (max-width: 1300px) {
    .speakers-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .logistics-wrapper {
        flex-direction: column;
    }

    .cards-wrapper {
        flex-direction: column;
    }

    .logistics-wrapper {
        flex-direction: column;
    }

    .logistics-card {
        width: 100%;
    }

    .main-title1 {
        font-size: 32px;
    }

    .box {
        width: calc((100% - 20px) / 2);
    }

    .conf-wrapper {
        flex-wrap: wrap;
        justify-content: center;
        gap: 40px 20px;
    }

    .conf-item:first-child {
        flex: 0 0 100%;
        max-width: 600px;
        margin: 0 auto;
    }
    .conf-item.center,
    .conf-item:last-child {
        flex: 0 0 calc(50% - 20px);
    }
}

@media (max-width: 768px) {
    .title {
        font-size: 34px;
    }
    
    .conf-wrapper {
        flex-direction: column;
        align-items: center;
    }

    .conf-item {
        width: 100%;
        margin-bottom: 30px;
    }

    .conf-title {
        font-size: 36px;
    }


    .menuBtn {
        display: inline;
        background-color: #1F3B8A;
        border: none;
        color: #fff;
    }

    .registerBtn {
        font-size: 14px;
        text-align: center;
        padding: 5px;
        border-radius: 5px;
    }

    menu {
        display: none;
    }

    .logotext {
        font-size: 14px;
    }

    .boxes {
        gap: 15px;
    }

    .box {
        width: 100%;
    }

    .sec2-inner {
        padding: 20px;
    }

    .speakers-grid {
        grid-template-columns: 1fr;
        row-gap: 60px;
    }

    .avatar {
        width: 160px;
        height: 160px;
    }

    .registration h2 {
        font-size: 32px;
    }

    .reg-card h3 {
        font-size: 20px;
    }

    .reg-card p {
        font-size: 16px;
    }

    .cards-wrapper {
        flex-direction: column;
        padding: 12px;
    }

    .container {
        padding: 0px;
    }

    .card {
        flex: none;
        padding: 10px;
    }

    .main-title {
        font-size: 28px;
    }

    .logistics-card {
        padding: 20px;
    }

    .footer-content {
        flex-direction: column;
        gap: 30px;
    }

    .footer-column {
        min-width: 100%;
    }

    .icon-span svg {
        width: 20px;
        height: 20px;
    }

    .dateLocal {
        gap: 5px;
        flex-wrap: wrap;
        justify-content: center;
    }

    .slesh {
        display: none;
    }

    menu.active {
        display: flex;
    }

    menu a {
        padding: 15px 30px;
        width: 100%;
        border-bottom: 1px solid rgba(255, 255, 255, 0.1);
    }

    menu a:last-child {
        border-bottom: none;
    }

    menu {
        display: flex;
        flex-direction: column;
        justify-content: flex-start;
        padding-top: 80px;

        position: fixed;
        top: 0;
        right: -300px;

        width: 280px;

        height: 100vh;
        background-color: #162a85;
        box-shadow: -5px 0 15px rgba(0, 0, 0, 0.3);

        transition: right 0.4s ease;

    }


    menu.active {
        right: 0;
    }

    menu a {
        padding: 20px 30px;
        font-size: 1.1rem;
        border-bottom: 1px solid rgba(255, 255, 255, 0.1);
    }


    .menu-overlay {
        display: none;
        position: sticky;
        top: 0;
        left: 0;
        width: 100%;
        height: 100%;
        background: rgba(0, 0, 0, 0.5);
        z-index: 900;
    }

    .menu-overlay.active {
        display: block;
    }

    .topics-wrapper {
        grid-template-columns: 1fr;
        gap: 40px;
    }

    .topics-content h2 {
        font-size: 36px;
        text-align: center;
    }

    .topics-lists {
        grid-template-columns: 1fr;
    }
}