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

body {
    font-family: 'Inter', sans-serif;
    background: #f5f9fc;
    color: #1f2937;
    line-height: 1.7;
}

.container {
    width: 90%;
    max-width: 1200px;
    margin: auto;
}

.section {
    padding: 80px 0;
}

.alt-section {
    background: #eef5fa;
}

.section-title {
    text-align: center;
    margin-bottom: 50px;
}

.section-title h2 {
    font-size: 2.5rem;
    margin-bottom: 12px;
}

.underline {
    width: 80px;
    height: 4px;
    background: #0f766e;
    margin: auto;
    border-radius: 10px;
}

.hero {
    min-height: 100vh;
    background:
        linear-gradient(rgba(3, 37, 65, 0.82), rgba(7, 89, 133, 0.75)),
        url('https://images.unsplash.com/photo-1506744038136-46273834b3fb?q=80&w=1400&auto=format&fit=crop');
    background-size: cover;
    background-position: center;
    color: white;
    padding: 30px 0;
}

.navbar {
    width: 90%;
    max-width: 1200px;
    margin: auto;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    font-size: 1.7rem;
    font-weight: 800;
}

.nav-links {
    display: flex;
    gap: 24px;
    list-style: none;
}

.nav-links a {
    color: white;
    text-decoration: none;
    font-weight: 500;
}

.menu-toggle {
    display: none;
    font-size: 2rem;
    cursor: pointer;
}

.hero-content {
    width: 90%;
    max-width: 1200px;
    margin: 90px auto 0;
    display: grid;
    grid-template-columns: 1.2fr 0.8fr;
    gap: 50px;
    align-items: center;
}

.tagline {
    color: #a5f3fc;
    text-transform: uppercase;
    letter-spacing: 2px;
    margin-bottom: 18px;
}

.hero-text h1 {
    font-size: 4rem;
    line-height: 1.1;
    margin-bottom: 15px;
}

.hero-text h2 {
    font-size: 1.5rem;
    font-weight: 400;
    margin-bottom: 25px;
}

.hero-description {
    max-width: 650px;
    margin-bottom: 35px;
}

.hero-buttons {
    display: flex;
    gap: 15px;
    flex-wrap: wrap;
}

.btn {
    padding: 14px 26px;
    border-radius: 10px;
    text-decoration: none;
    font-weight: 600;
}

.primary-btn {
    background: #0f766e;
    color: white;
}

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

.hero-card {
    border-radius: 24px;
    overflow: hidden;
    background: rgba(255,255,255,0.08);
    backdrop-filter: blur(10px);
    border: 1px solid rgba(255,255,255,0.15);
}

.hero-card-content {
    padding: 40px;
}

.hero-card ul {
    list-style: none;
}

.hero-card li {
    padding: 12px 0;
    border-bottom: 1px solid rgba(255,255,255,0.15);
}

.about-grid {
    display: grid;
    grid-template-columns: 1.3fr 0.7fr;
    gap: 40px;
}

.about-info {
    background: white;
    padding: 30px;
    border-radius: 18px;
    box-shadow: 0 10px 30px rgba(0,0,0,0.05);
}

.info-item {
    margin-bottom: 20px;
}

.info-label {
    display: block;
    font-weight: 700;
    color: #0f766e;
    margin-bottom: 5px;
}

.timeline {
    position: relative;
    max-width: 900px;
    margin: auto;
}

.timeline::before {
    content: '';
    position: absolute;
    left: 20px;
    top: 0;
    width: 4px;
    height: 100%;
    background: #0f766e;
}

.timeline-item {
    position: relative;
    padding-left: 70px;
    margin-bottom: 50px;
}

.timeline-item::before {
    content: '';
    position: absolute;
    left: 10px;
    top: 5px;
    width: 22px;
    height: 22px;
    border-radius: 50%;
    background: #0f766e;
}

.timeline-content,
.card,
.project-card,
.skill-box,
.research-item {
    background: white;
    padding: 25px;
    border-radius: 18px;
    box-shadow: 0 10px 25px rgba(0,0,0,0.05);
}

.cards-grid,
.project-grid,
.skills-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 25px;
}

.contact-section {
    background: linear-gradient(135deg, #0f172a, #0f766e);
    color: white;
}

.contact-box {
    text-align: center;
}

footer {
    background: #020617;
    color: white;
    text-align: center;
    padding: 25px;
}

@media (max-width: 900px) {

    .hero-content,
    .about-grid {
        grid-template-columns: 1fr;
    }

    .hero-text h1 {
        font-size: 2.8rem;
    }

    .nav-links {
        position: absolute;
        top: 80px;
        right: 5%;
        background: rgba(15, 23, 42, 0.96);
        flex-direction: column;
        padding: 25px;
        border-radius: 14px;
        display: none;
    }

    .nav-links.active {
        display: flex;
    }

    .menu-toggle {
        display: block;
    }
}