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

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    line-height: 1.6;
    color: #333;
}



/* Header Styles */
header {
    background: linear-gradient(135deg, #0e7490 0%, #0891b2 100%);
    padding: 1rem 0;
    position: fixed;
    width: 100%;
    top: 0;
    z-index: 1000;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

nav {
    max-width: 1200px;
    margin: 0 auto;
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0 2rem;
    flex-wrap: wrap;
}

.logo {
    display: flex;
    align-items: center;
    gap: 10px;
    color: white;
    font-size: clamp(1.2rem, 3vw, 1.5rem);
    font-weight: bold;
}

.logo-icon {
    width: 60px;
    height: 60px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    color: #667eea;
    flex-shrink: 0;
}

nav ul {
    display: flex;
    list-style: none;
    gap: 2rem;
    flex-wrap: wrap;
}

nav ul li a {
    /* color: black; */
    color: white;
    text-decoration: none;
    font-weight: 500;
    transition: opacity 0.3s;
    font-size: clamp(0.9rem, 2vw, 1rem);
}

nav ul li a:hover {
    opacity: 0.8;
}


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

/* Hero Section */

.hero{
    margin-top: 80px;
    background-image: url("../images/talk_banner.png");
    background-size: cover;
    background-position: center;
    min-height: 600px;
    height: clamp(400px, 60vh, 500px);
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    color: black;
    padding: 2rem;
}

.hero-content {
    background: rgba(255, 255, 255, 0.7); /* semi‑transparent box */
    padding: 25px 40px;
    border-radius: 10px;
    max-width: 800px;
}
.hero-content h1 {
    font-size: clamp(2.5rem, 5vw, 4rem);
    margin-bottom: 1rem;
    font-weight: 700;
}

.hero-content p {
    font-size: clamp(1.1rem, 2vw, 1.5rem);
    opacity: 0.95;
}
.hero-subtitle {
    font-size: clamp(1.3rem, 3vw, 2rem);
    margin-bottom: 1.5rem;
    font-weight: 400;
    opacity: 0.95;
}

.hero-description {
    font-size: clamp(1rem, 2vw, 1.2rem);
    margin-bottom: 2.5rem;
    line-height: 1.8;
    opacity: 0.9;
}

.hero-buttons {
    display: flex;
    gap: 20px;
    justify-content: center;
        flex-wrap: wrap;
}

.btn-primary,
.btn-secondary {
    padding: 14px 28px;
    border-radius: 30px;
    text-decoration: none;
    font-weight: 600;
    transition: all 0.3s;
}

.btn-primary {
    background: white;
    color: #0891b2;
}

.btn-primary:hover {
    transform: translateY(-2px);
}

.btn-secondary {
    border: 2px solid white;
    color: #0891b2;
}

.btn-secondary:hover {
    background: white;
    color: #0891b2;
}

/* Stats */
.stats-section {
    padding: 60px 0;
    background: #f7f9fc;
}

.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit,minmax(200px,1fr));
    gap: 30px;
    text-align: center;
}

.stat-number {
    font-size: 2.5rem;
    font-weight: 800;
    color: #0891b2;
}

.stat-label {
    margin-top: 8px;
    color: #0891b2;
}

/* Section headers */
.section-header {
    text-align: center;
    margin-bottom: 50px;
}

.section-header h2 {
    font-size: 2.2rem;
    margin-bottom: 10px;
    color:#0891b2 ;
}

/* Featured talk */
.featured-section {
    padding: 80px 0;
}

.featured-talk {
    display: grid;
    grid-template-columns: 1.2fr 1fr;
    gap: 40px;
    align-items: center;
}

.featured-video {
    width: 100%;
    border-radius: 10px;
}

.video-duration {
    position: absolute;
}

.featured-info h3 {
    font-size: 1.8rem;
    margin: 10px 0;
}

.talk-category {
    color: #0891b2;
    font-weight: 600;
}

.speaker-info {
    display: flex;
    gap: 15px;
    align-items: center;
    margin: 20px 0;
}

.speaker-avatar svg {
    width: 50px;
}

.talk-meta {
    display: flex;
    gap: 20px;
    margin: 20px 0;
}

.btn-watch {
    padding: 12px 20px;
    border: none;
    background: #0891b2;
    color: white;
    border-radius: 25px;
    cursor: pointer;
    width: 500px;
}

.team-photo {
    width: clamp(120px, 25vw, 150px);
    height: clamp(120px, 25vw, 150px);
    margin: 0 auto 1.5rem;
    border-radius: 50%;
    overflow: hidden;
    border: 4px solid #667eea;
    display: flex;
}

/* Topics */
.topics-section {
    padding: 80px 0;
    background: #f7f9fc;
}

.topics-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit,minmax(180px,1fr));
    gap: 25px;
}

.topic-card {
    background: white;
    padding: 30px;
    border-radius: 12px;
    text-align: center;
    transition: 0.3s;
    cursor: pointer;
}

.topic-card h4 {
    color: #fdc50e;
}

.topic-card:hover {
    transform: translateY(-5px);
}

.topic-icon {
    font-size: 2rem;
    margin-bottom: 10px;
}

/* Talks grid */
.talks-section {
    padding: 80px 0;
}

.filter-tabs {
    margin-top: 20px;
}

.tab-btn {
    padding: 10px 18px;
    border: none;
    margin: 5px;
    background: #eee;
    border-radius: 20px;
    cursor: pointer;
}

.tab-btn.active {
    background: #0891b2;
    color: white;
}

.talks-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit,minmax(280px,1fr));
    gap: 30px;
    margin-top: 40px;
}

.talk-card {
    background: white;
    border-radius: 12px;
    overflow: hidden;
    box-shadow: 0 5px 20px rgba(0,0,0,0.06);
    transition: 0.3s;
}

.talk-card:hover {
    transform: translateY(-6px);
}

.talk-thumbnail img,
.talk-thumbnail svg {
    width: 100%;
}

.talk-content {
    padding: 20px;
}

.talk-title {
    text-align: center;
    font-size: 1.1rem;
    margin: 10px 5px;
}

.talk-speaker {
    /* display: flex; */
    gap: 10px;
    margin: 5px 0;
}

.speaker-mini-avatar svg {
    width: 35px;
}

.talk-stats {
    display: flex;
    gap: 15px;
    margin-top: 10px;
}

.more-talk {
    margin-top: 20px;
    display: flex;
    justify-content: center;
}


.more-talk a {
    text-decoration: none;
    padding: 12px 24px;
    border-radius: 25px;
    background: #0891b2;
    color: white;
    font-weight: 600;
}

/* Speakers */
.speakers-section {
    padding: 80px 0;
    background: #f7f9fc;
}

.speakers-carousel {
    display: grid;
    grid-template-columns: repeat(auto-fit,minmax(300px,1fr));
    gap: 30px;
}

.speaker-spotlight {
    background: white;
    padding: 30px;
    border-radius: 12px;
    text-align: center;
}

.speaker-photo svg {
    width: 120px;
    margin-bottom: 15px;
}

.speaker-spotlight .speaker-role {
    color: #0891b2;
    font-weight: 600;
    font-size: 1rem;
    margin-bottom: 12px;
}
/* Submit */
.submit-section {
    padding: 80px 0;
}

.submit-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 40px;
}

.submit-form-container {
    background: #f7f9fc;
    padding: 30px;
    border-radius: 10px;
}

.submit-form input,
.submit-form select,
.submit-form textarea {
    width: 100%;
    padding: 12px;
    margin-bottom: 15px;
    border: 1px solid #ddd;
    border-radius: 6px;
}

.btn-submit {
    background: #0891b2;
    border: none;
    color: white;
    padding: 12px;
    width: 100%;
    border-radius: 6px;
}

/* Newsletter */
.newsletter-section {
    padding: 60px 0;
    background: linear-gradient(135deg, #0e7490 0%, #0891b2 100%);
    color: white;
    text-align: center;
    margin-bottom: 50px;
}

.newsletter-form {
    margin-top: 20px;
}

.newsletter-form input {
    padding: 12px;
    border: none;
    border-radius: 20px;
    width: 220px;
}

.newsletter-form button {
    padding: 12px 18px;
    border: none;
    border-radius: 20px;
    background: white;
    color: #667eea;
    margin-left: 10px;
}



/* Footer Styles */
footer {
    background:linear-gradient(135deg, #0e7490 0%, #0891b2 100%);
    color: white;
    padding: 3rem 0 1rem;
}

.footer-content {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 2rem;
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
    margin-bottom: 2rem;
}

.footer-section h3 {
    margin-bottom: 1rem;
    color: #fdc50e;
}

.footer-section p,
.footer-section ul {
    color: white;
    line-height: 1.8;
}

.footer-section ul {
    list-style: none;
}

.footer-section ul li {
    margin-bottom: 0.5rem;
}

.footer-section ul li a {
    color: white;
    text-decoration: none;
    transition: color 0.3s;
}

.footer-section ul li a:hover {
    opacity: 0.8;
}

.social-links {
    display: flex;
    gap: 1rem;
    margin-top: 1rem;
}

.social-links a {
    width: 40px;
    height: 40px;
    background: white;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: black;
    text-decoration: none;
    transition: background 0.3s;
}

.social-links a:hover {
    background: gainsboro;
}

.footer-bottom {
    text-align: center;
    padding-top: 2rem;
    border-top: 1px solid #34495e;
    color: white;
}



/* Responsive Design */
@media (max-width: 768px) {
    nav ul {
        flex-direction: column;
        gap: 1rem;
    }

    .banner-content h1 {
        font-size: 2rem;
    }

    .banner-content p {
        font-size: 1.2rem;
    }

    .section-title {
        font-size: 2rem;
    }
}