:root {
    --primary: #22d3ee;
    --primary-dark: #0891b2;
    --secondary: #f2c14e;
    --dark: #0b1220;
    --light: #f4f7fb;
    --gray: #9aa8ba;
    --accent: #22d3ee;
    --surface: #111b2c;
    --surface-raised: #162235;
    --border: rgba(154, 168, 186, 0.24);
    --transition: 180ms ease;
}

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

html {
    scroll-behavior: smooth;
    scroll-padding-top: 88px;
}

body {
    font-family: 'IBM Plex Sans', sans-serif;
    background: var(--dark);
    color: var(--light);
    line-height: 1.6;
    overflow-x: hidden;
    position: relative;
}

body::before {
    content: '';
    position: fixed;
    inset: 0;
    z-index: -2;
    background-image:
        linear-gradient(rgba(154, 168, 186, 0.035) 1px, transparent 1px),
        linear-gradient(90deg, rgba(154, 168, 186, 0.035) 1px, transparent 1px);
    background-size: 48px 48px;
    pointer-events: none;
}

#particles-js {
    position: fixed;
    inset: 0;
    width: 100%;
    height: 100%;
    z-index: 0 !important;
}

.container {
    width: 100%;
    max-width: 1160px;
    margin: 0 auto;
    padding: 0 2rem;
}

header,
header.scrolled {
    padding: 1rem 0;
    position: fixed;
    width: 100%;
    z-index: 100;
    background: rgba(11, 18, 32, 0.94);
    border-bottom: 1px solid var(--border);
    box-shadow: none;
    backdrop-filter: blur(12px);
    transition: background-color var(--transition), border-color var(--transition);
}

.header-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    gap: 0.75rem;
}

.logo-icon {
    width: 34px;
    height: 34px;
    border: 1px solid var(--accent);
    border-radius: 3px;
    background: transparent;
}

.logo-icon::before {
    display: none;
}

.logo-icon i {
    color: var(--accent);
    font-size: 1rem;
}

.logo-text,
.footer-logo {
    font-family: 'IBM Plex Sans', sans-serif;
    color: var(--light);
    background: none;
    -webkit-text-fill-color: currentColor;
}

.logo-text {
    font-size: 1.05rem;
    font-weight: 600;
}

nav ul {
    display: flex;
    list-style: none;
    align-items: center;
    gap: 1.5rem;
}

nav a {
    position: relative;
    padding: 0.5rem 0;
    color: var(--light);
    text-decoration: none;
    font-size: 0.9rem;
    font-weight: 500;
    transition: color var(--transition);
}

nav a::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 1px;
    background: var(--accent);
    transition: width var(--transition);
}

nav a:hover {
    color: var(--accent);
}

nav a:hover::after {
    width: 100%;
}

nav a.service-link {
    padding: 0.45rem 0.7rem;
    border: 1px solid rgba(34, 211, 238, 0.55);
    border-radius: 3px;
    color: var(--accent);
}

nav a.service-link::after {
    display: none;
}

nav a.service-link:hover {
    background: rgba(34, 211, 238, 0.08);
}

.hero {
    min-height: 88vh;
    padding: 8rem 0 5rem;
}

.hero-content {
    max-width: 760px;
}

.hero-subtitle {
    margin-bottom: 0.45rem;
    font-family: 'IBM Plex Mono', monospace;
    font-size: 0.84rem;
    font-weight: 500;
    letter-spacing: 0;
}

.hero-title,
.section-title,
.about-text h3,
.expertise-text h4,
.research-card h3,
.pub-title,
.contact-info h3,
.contact-detail h4 {
    font-family: 'IBM Plex Sans', sans-serif;
}

.hero-title {
    max-width: 720px;
    margin-top: 1.25rem;
    font-size: clamp(2.8rem, 6vw, 5.3rem);
    font-weight: 600;
    line-height: 1.03;
    color: var(--light);
    background: none;
    -webkit-text-fill-color: currentColor;
}

.hero-text {
    max-width: 650px;
    font-size: 1.18rem;
}

.hero-btns {
    flex-wrap: wrap;
}

.btn {
    display: inline-block;
    padding: 0.78rem 1.2rem;
    border: 0;
    border-radius: 3px;
    font-family: 'IBM Plex Sans', sans-serif;
    font-size: 0.92rem;
    font-weight: 600;
    letter-spacing: 0;
    text-align: center;
    text-decoration: none;
    cursor: pointer;
    transition: background-color var(--transition), border-color var(--transition), color var(--transition);
}

.btn-primary {
    border: 1px solid var(--accent);
    background: var(--accent);
    color: #07121a;
    box-shadow: none;
}

.btn-primary:hover {
    transform: none;
    background: #67e8f9;
    border-color: #67e8f9;
    box-shadow: none;
}

.btn-outline {
    border: 1px solid rgba(34, 211, 238, 0.7);
}

.btn-outline:hover {
    transform: none;
    background: rgba(34, 211, 238, 0.08);
}

.section {
    padding: 7rem 0;
    border-top: 1px solid var(--border);
}

#about {
    border-top: 0;
}

.section-title {
    margin-bottom: 4rem;
    font-size: 2.25rem;
    font-weight: 600;
    text-align: left;
}

.section-title::after {
    bottom: -1.15rem;
    left: 0;
    width: 52px;
    height: 2px;
    transform: none;
    border-radius: 0;
    background: var(--accent);
}

.about-content {
    grid-template-columns: minmax(280px, 0.8fr) minmax(0, 1.2fr);
}

.about-img {
    border: 1px solid var(--border);
    border-radius: 4px;
    box-shadow: 16px 16px 0 rgba(34, 211, 238, 0.08);
    transform: none;
}

.about-img:hover {
    transform: none;
}

.about-img img,
.about-img:hover img {
    transform: none;
}

.about-text h3,
.contact-info h3 {
    color: var(--light);
}

.expertise-list {
    gap: 1.25rem 2rem;
    padding-top: 2rem;
    border-top: 1px solid var(--border);
}

.expertise-icon,
.contact-icon {
    width: 42px;
    height: 42px;
    border: 1px solid rgba(34, 211, 238, 0.45);
    border-radius: 3px;
    background: transparent;
}

.expertise-icon i,
.contact-icon i {
    color: var(--accent);
    font-size: 1rem;
}

.research {
    background: rgba(17, 27, 44, 0.78);
}

.research-content {
    max-width: none;
}

.research-intro {
    max-width: 760px;
    margin: 0 0 3rem;
    text-align: left;
}

.research-grid {
    gap: 1px;
    border: 1px solid var(--border);
    background: var(--border);
}

.research-card {
    padding: 2.25rem;
    border: 0;
    border-radius: 0;
    background: rgba(11, 18, 32, 0.92);
    box-shadow: none;
}

.research-card::before {
    display: none;
}

.research-card:hover {
    transform: none;
    border-color: transparent;
    background: var(--surface-raised);
    box-shadow: none;
}

.research-icon {
    font-size: 1.7rem;
}

.research-card ul {
    padding-left: 1.15rem;
    color: rgba(244, 247, 251, 0.78);
}

.research-card li + li {
    margin-top: 0.65rem;
}

.pub-item {
    margin-bottom: 0;
    padding: 2rem 0;
    border: 0;
    border-top: 1px solid var(--border);
    border-radius: 0;
    background: transparent;
    backdrop-filter: none;
}

.pub-item:last-child {
    border-bottom: 1px solid var(--border);
}

.pub-item:hover {
    transform: none;
    background: transparent;
}

.pub-meta {
    color: var(--gray);
}

.contact {
    background: var(--surface);
}

.contact-content {
    gap: 5rem;
}

.contact-methods {
    padding-top: 1rem;
}

.social-link {
    border: 1px solid var(--border);
    border-radius: 3px;
    background: transparent;
    transition: color var(--transition), border-color var(--transition), background-color var(--transition);
}

.social-link:hover {
    transform: none;
    border-color: var(--accent);
    background: rgba(34, 211, 238, 0.08);
    color: var(--accent);
}

.contact-form input,
.contact-form textarea {
    border-radius: 3px;
    background: rgba(7, 13, 24, 0.7);
    font-family: 'IBM Plex Sans', sans-serif;
    transition: border-color var(--transition), box-shadow var(--transition);
}

footer {
    background: #070d18;
}

a:focus-visible,
button:focus-visible,
input:focus-visible,
textarea:focus-visible {
    outline: 2px solid var(--secondary);
    outline-offset: 3px;
}

@media (max-width: 900px) {
    .header-content {
        align-items: flex-start;
        gap: 0.8rem;
    }

    .about-content {
        grid-template-columns: 1fr;
        gap: 3rem;
    }

    nav ul {
        flex-wrap: wrap;
        justify-content: flex-end;
        gap: 0.55rem 1rem;
    }
}

@media (max-width: 768px) {
    .section {
        padding: 5rem 0;
    }

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

    .hero-title {
        font-size: clamp(2.55rem, 12vw, 4.25rem);
    }
}

@media (max-width: 620px) {
    .container {
        padding: 0 1.25rem;
    }

    header,
    header.scrolled {
        position: absolute;
        padding: 0.8rem 0;
    }

    .header-content {
        flex-direction: column;
    }

    nav,
    nav ul {
        width: 100%;
    }

    nav ul {
        justify-content: flex-start;
        gap: 0.4rem 0.7rem;
    }

    nav a {
        font-size: 0.76rem;
    }

    nav a.service-link {
        padding: 0.32rem 0.5rem;
    }

    .hero {
        min-height: auto;
        padding: 9.5rem 0 2.5rem;
    }

    .hero-subtitle {
        font-size: 0.72rem;
    }

    .hero-title {
        margin: 0.9rem 0 1rem;
        font-size: 2.2rem;
        line-height: 1.05;
    }

    .hero-text {
        margin-bottom: 1.5rem;
        font-size: 1rem;
    }

    .hero-btns {
        display: grid;
        grid-template-columns: 1fr 1fr;
        gap: 0.65rem;
    }

    .hero-btns .btn {
        width: auto;
    }

    .hero-btns .btn:first-child {
        grid-column: 1 / -1;
    }
}

@media (prefers-reduced-motion: reduce) {
    html {
        scroll-behavior: auto;
    }

    *,
    *::before,
    *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }
}