:root {
    --primary-color: #006994;
    --secondary-color: #004466;
    --accent-color: #00b4d8;
    --light-color: #caf0f8;
    --dark-color: #03045e;
    --text-color: #333;
    --white: #ffffff;
}

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

body {
    font-family: 'Arial', sans-serif;
    line-height: 1.6;
    color: var(--text-color);
}

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

/* Header and Navigation */
header {
    background-color: rgba(255, 255, 255, 0.1);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    position: fixed;
    width: 100%;
    top: 0;
    z-index: 1000;
    box-shadow: 0 2px 5px rgba(0, 0, 0, 0.1);
    transition: background-color 0.3s ease;
}

header.header-scrolled {
    background-color: var(--primary-color);
    backdrop-filter: none;
    -webkit-backdrop-filter: none;
}

nav {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem 2rem;
    max-width: 1200px;
    margin: 0 auto;
}

.logo {
    color: var(--white);
    font-size: 1.5rem;
    font-weight: bold;
}

.nav-links a {
    color: var(--white);
    text-decoration: none;
    margin-left: 2rem;
    transition: color 0.3s ease;
}

.nav-links a:hover {
    color: var(--light-color);
}

/* Hero Section */
.hero {
    height: 100vh;
    background: linear-gradient(rgba(0, 0, 0, 0.5), rgba(0, 0, 0, 0.5)),
                url('../images/hero-bg.jpg') center/cover;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    color: var(--white);
    position: relative;
    overflow: hidden;
}

.wave-container {
    position: absolute;
    bottom: 0;
    left: 0;
    width: 100%;
    overflow: hidden;
    line-height: 0;
    transform: rotate(180deg);
}

.waves {
    position: relative;
    width: 100%;
    height: 100px;
    margin-bottom: -7px;
    min-height: 100px;
    max-height: 150px;
}

.parallax > use {
    animation: move-forever 25s cubic-bezier(.55,.5,.45,.5) infinite;
}
.parallax > use:nth-child(1) { animation-delay: -2s; animation-duration: 7s; }
.parallax > use:nth-child(2) { animation-delay: -3s; animation-duration: 10s; }
.parallax > use:nth-child(3) { animation-delay: -4s; animation-duration: 13s; }
.parallax > use:nth-child(4) { animation-delay: -5s; animation-duration: 20s; }

@keyframes move-forever {
    0% { transform: translate3d(-90px,0,0); }
    100% { transform: translate3d(85px,0,0); }
}

.hero-content {
    position: relative;
    z-index: 1;
    max-width: 800px;
    padding: 2rem;
    text-align: center;
}

.hero-content h1 {
    font-size: 4.5rem;
    margin-bottom: 0.5rem;
    text-shadow: 2px 2px 4px rgba(0,0,0,0.3);
    animation: fadeInDown 1s ease-out;
}

.hero-content h2 {
    font-size: 2.5rem;
    margin-bottom: 1.5rem;
    color: var(--light-color);
    text-shadow: 1px 1px 3px rgba(0,0,0,0.3);
    animation: fadeInDown 1s ease-out 0.3s both;
}

.hero-content p {
    font-size: 1.2rem;
    margin-bottom: 2rem;
    animation: fadeInDown 1s ease-out 0.6s both;
}

.hero-cta {
    animation: fadeInUp 1s ease-out 0.9s both;
}

.cta-button {
    display: inline-block;
    padding: 1rem 2rem;
    background: linear-gradient(45deg, var(--primary-color), var(--accent-color));
    color: var(--white);
    text-decoration: none;
    border-radius: 30px;
    font-weight: bold;
    text-transform: uppercase;
    letter-spacing: 1px;
    transition: all 0.3s ease;
    box-shadow: 0 4px 15px rgba(0,0,0,0.2);
}

.cta-button:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(0,0,0,0.3);
    background: linear-gradient(45deg, var(--accent-color), var(--primary-color));
}

@keyframes fadeInDown {
    from {
        opacity: 0;
        transform: translateY(-20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.hero-content {
    padding: 2rem;
}

.hero h1 {
    font-size: 4rem;
    margin-bottom: 0.5rem;
}

.hero h2 {
    font-size: 2rem;
    margin-bottom: 1rem;
}

/* Sections */
section {
    padding: 5rem 0;
}

section h2 {
    text-align: center;
    color: var(--primary-color);
    margin-bottom: 3rem;
    font-size: 2.5rem;
}

/* About Section */
.about {
    background-color: var(--white);
}

.about-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 2rem;
}

.researcher-profile, .company-profile {
    background-color: rgba(255, 255, 255, 0.9);
    padding: 2rem;
    border-radius: 15px;
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.1);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.researcher-profile:hover, .company-profile:hover {
    transform: translateY(-5px);
    box-shadow: 0 6px 25px rgba(0, 0, 0, 0.15);
}

.profile-header {
    display: flex;
    align-items: center;
    margin-bottom: 2rem;
    gap: 2rem;
}

.profile-photo {
    width: 150px;
    height: 150px;
    border-radius: 50%;
    overflow: hidden;
    border: 4px solid var(--light-color);
    box-shadow: 0 4px 15px rgba(0, 105, 148, 0.2);
    transition: transform 0.3s ease;
}

.profile-photo img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform 0.3s ease;
}

.researcher-profile:hover .profile-photo {
    transform: scale(1.05);
}

.profile-header h3 {
    color: var(--primary-color);
    font-size: 1.8rem;
    margin: 0;
    flex: 1;
}

.credentials, .education {
    margin-bottom: 1.5rem;
}

.credentials strong {
    color: var(--primary-color);
}

.research-link {
    display: inline-flex;
    align-items: center;
    text-decoration: none;
    color: var(--primary-color);
    margin-top: 1rem;
    padding: 0.5rem 1rem;
    border-radius: 20px;
    background-color: var(--light-color);
    transition: all 0.3s ease;
}

.research-link:hover {
    background-color: var(--primary-color);
    color: var(--white);
    transform: translateY(-2px);
}

.social-icon {
    width: 20px;
    height: 20px;
    margin-right: 8px;
    transition: transform 0.3s ease;
}

.research-link:hover .social-icon {
    transform: scale(1.1);
}

.profile-description {
    line-height: 1.8;
}

.achievements ul {
    list-style: none;
    margin-top: 1.5rem;
}

.achievements li {
    position: relative;
    padding-left: 1.5rem;
    margin-bottom: 0.8rem;
    line-height: 1.4;
}

.achievements li:before {
    content: "•";
    color: var(--accent-color);
    font-size: 1.5em;
    position: absolute;
    left: 0;
    top: -0.2rem;
}

/* Expertise Section */
.expertise {
    background-color: var(--light-color);
}

.expertise-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
}

.expertise-item {
    background-color: var(--white);
    padding: 2rem;
    border-radius: 12px;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.1);
    transition: all 0.3s ease;
    text-align: center;
    position: relative;
    overflow: hidden;
}

.expertise-item::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: linear-gradient(to right, var(--primary-color), var(--accent-color));
    opacity: 0;
    transition: opacity 0.3s ease;
}

.expertise-item:hover {
    transform: translateY(-5px);
    box-shadow: 0 6px 20px rgba(0, 0, 0, 0.15);
}

.expertise-item:hover::before {
    opacity: 1;
}

.expertise-icon {
    width: 80px;
    height: 80px;
    margin: 0 auto 1.5rem;
    display: flex;
    align-items: center;
    justify-content: center;
    background-color: var(--light-color);
    border-radius: 50%;
    padding: 1.2rem;
    transition: transform 0.3s ease;
}

.expertise-item:hover .expertise-icon {
    transform: scale(1.1);
}

.expertise-icon img {
    width: 100%;
    height: 100%;
    object-fit: contain;
    filter: brightness(0) saturate(100%) invert(27%) sepia(89%) saturate(1475%) hue-rotate(182deg) brightness(94%) contrast(102%);
}

.expertise-item h3 {
    color: var(--primary-color);
    margin: 1rem 0;
    font-size: 1.4rem;
}

/* Research Section */
.research {
    background-color: var(--white);
}

.research-content {
    max-width: 1000px;
    margin: 0 auto;
}

.research-intro {
    text-align: center;
    margin-bottom: 3rem;
    font-size: 1.1rem;
}

.research-highlights {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
}

.highlight-item {
    background-color: rgba(255, 255, 255, 0.9);
    padding: 2rem;
    border-radius: 8px;
    box-shadow: 0 2px 15px rgba(0, 0, 0, 0.1);
}

.highlight-item h3 {
    color: var(--primary-color);
    margin-bottom: 1.2rem;
    font-size: 1.3rem;
}

.research-list, .publication-list {
    list-style: none;
    padding-left: 0;
}

.research-list li, .publication-list li {
    position: relative;
    padding-left: 1.5rem;
    margin-bottom: 1rem;
    line-height: 1.4;
}

.research-list li:before {
    content: "→";
    color: var(--accent-color);
    position: absolute;
    left: 0;
}

.publication-list li:before {
    content: "📄";
    position: absolute;
    left: 0;
}

/* Contact Section */
.contact {
    background-color: var(--light-color);
}

.contact-content {
    text-align: center;
    max-width: 600px;
    margin: 0 auto;
}

.contact-info {
    margin-top: 2rem;
}

/* Footer */
footer {
    background-color: var(--primary-color);
    color: var(--white);
    text-align: center;
    padding: 2rem 0;
}

/* Responsive Design */
@media (max-width: 768px) {
    .nav-links {
        display: none;
    }

    .hero h1 {
        font-size: 2.5rem;
    }

    .hero h2 {
        font-size: 1.5rem;
    }

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

    section {
        padding: 3rem 0;
    }

    .profile-header {
        flex-direction: column;
        text-align: center;
    }

    .profile-photo {
        width: 120px;
        height: 120px;
        margin: 0 auto;
    }

    .expertise-grid {
        grid-template-columns: 1fr;
    }

    .waves {
        height: 40px;
        min-height: 40px;
    }

    .research-highlights {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 480px) {
    .hero-content h1 {
        font-size: 2rem;
    }

    .hero-content h2 {
        font-size: 1.2rem;
    }

    .cta-button {
        padding: 0.8rem 1.5rem;
        font-size: 0.9rem;
    }

    .container {
        padding: 0 15px;
    }
}

/* Responsive Design */
@media (max-width: 768px) {
    .nav-links {
        display: none;
    }

    .hero h1 {
        font-size: 2.5rem;
    }

    .hero h2 {
        font-size: 1.5rem;
    }

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

    section {
        padding: 3rem 0;
    }
}