:root {
    --bg-primary: #0a0e14;
    --bg-card: rgba(31, 42, 60, 0.5);
    --text-main: #e6e6e6;
    --text-muted: #8b9bb4;
    --accent: #00ff9d;
    --border-color: #1f2a3c;
    --border-card: #1a2332;
}

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

html {
    scroll-behavior: smooth;
    scroll-padding-top: 64px;
}

body {
    font-family: system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    background-color: var(--bg-primary);
    color: var(--text-main);
    line-height: 1.6;
}

a {
    color: var(--accent);
    text-decoration: none;
    transition: opacity 0.2s ease;
}

a:hover {
    opacity: 0.8;
}

a:focus-visible,
button:focus-visible {
    outline: 2px solid var(--accent);
    outline-offset: 3px;
    border-radius: 2px;
}

/* Skip-link */
.skip-link {
    position: absolute;
    top: -100px;
    left: 0;
    background: var(--accent);
    color: var(--bg-primary);
    padding: 0.75rem 1.25rem;
    z-index: 1000;
    font-weight: 600;
    transition: top 0.2s ease;
}

.skip-link:focus {
    top: 0;
    outline: 2px solid var(--bg-primary);
    outline-offset: -4px;
}

/* Header */
.header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    height: 64px;
    background-color: rgba(10, 14, 20, 0.9);
    backdrop-filter: blur(8px);
    -webkit-backdrop-filter: blur(8px);
    border-bottom: 1px solid var(--border-color);
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0 2rem;
    z-index: 100;
}

.logo {
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--accent);
    letter-spacing: -0.02em;
}

.nav {
    display: flex;
    gap: 2rem;
}

.nav a {
    color: var(--text-main);
    font-size: 0.95rem;
    opacity: 0.8;
}

.nav a:hover,
.nav a:focus-visible {
    opacity: 1;
}

/* Hero */
.hero {
    min-height: calc(100vh - 64px);
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 2rem;
    text-align: center;
}

.hero-content {
    max-width: 800px;
}

.hero h1 {
    font-size: clamp(2.5rem, 6vw, 4rem);
    line-height: 1.1;
    margin-bottom: 1.5rem;
    letter-spacing: -0.03em;
}

.hero p {
    font-size: clamp(1.125rem, 2.5vw, 1.375rem);
    color: var(--text-muted);
    margin-bottom: 2rem;
}

/* Services */
.services {
    padding: 6rem 2rem;
    max-width: 1200px;
    margin: 0 auto;
}

.section-title {
    font-size: clamp(1.5rem, 3vw, 2rem);
    text-align: center;
    margin-bottom: 3rem;
}

.services-grid {
    display: grid;
    gap: 1.5rem;
}

@media (min-width: 768px) {
    .services-grid {
        grid-template-columns: repeat(2, minmax(250px, 1fr));
    }
}

@media (min-width: 992px) {
    .services-grid {
        grid-template-columns: repeat(3, minmax(300px, 1fr));
    }
}

.service-card {
    background-color: var(--bg-card);
    border: 1px solid var(--border-card);
    padding: 1.75rem;
    border-radius: 8px;
    transition: border-color 0.2s ease, transform 0.2s ease;
}

.service-card:hover {
    border-color: var(--accent);
    transform: translateY(-2px);
}

.service-icon {
    width: 36px;
    height: 36px;
    fill: none;
    stroke: var(--accent);
    stroke-width: 1.5;
    stroke-linecap: round;
    stroke-linejoin: round;
    margin-bottom: 1rem;
}

.service-card h3 {
    font-size: 1.125rem;
    margin-bottom: 0.75rem;
}

.service-card p {
    color: var(--text-muted);
    font-size: 0.9rem;
}

/* About */
.about {
    padding: 6rem 2rem;
    max-width: 1200px;
    margin: 0 auto;
}

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

.about-text h2 {
    font-size: clamp(1.5rem, 3vw, 2rem);
    margin-bottom: 1.5rem;
}

.about-text p {
    color: var(--text-muted);
    margin-bottom: 1rem;
}

.skills-list {
    list-style: none;
    display: flex;
    flex-wrap: wrap;
    gap: 0.75rem;
    margin-top: 1.5rem;
}

.skill-tag {
    background-color: rgba(0, 255, 157, 0.1);
    border: 1px solid var(--accent);
    color: var(--accent);
    padding: 0.375rem 0.875rem;
    border-radius: 4px;
    font-size: 0.875rem;
}

.about-stats {
    display: grid;
    gap: 1rem;
}

.stat-item {
    background-color: var(--bg-card);
    border: 1px solid var(--border-color);
    padding: 1.25rem;
    border-radius: 8px;
}

.stat-item h4 {
    color: var(--accent);
    font-size: 0.9375rem;
    margin-bottom: 0.375rem;
}

.stat-item p {
    color: var(--text-muted);
    font-size: 1.25rem;
    font-weight: 600;
}

/* Contacts */
.contacts {
    padding: 6rem 2rem;
    max-width: 800px;
    margin: 0 auto;
    text-align: center;
}

.contacts h2 {
    font-size: clamp(1.5rem, 3vw, 2rem);
    margin-bottom: 2rem;
}

.contact-links {
    display: flex;
    justify-content: center;
    gap: 1.5rem;
    flex-wrap: wrap;
}

.contact-link {
    background-color: var(--bg-card);
    border: 1px solid var(--border-color);
    padding: 1rem 1.75rem;
    border-radius: 8px;
    display: flex;
    align-items: center;
    gap: 0.75rem;
    transition: border-color 0.2s ease, transform 0.2s ease;
}

.contact-link:hover {
    border-color: var(--accent);
    transform: translateY(-2px);
}

/* Footer */
.footer {
    padding: 1.5rem 2rem;
    text-align: center;
    color: var(--text-muted);
    font-size: 0.875rem;
    border-top: 1px solid var(--border-color);
}

.footer p {
    margin-bottom: 0.5rem;
}

.footer p:last-child {
    margin-bottom: 0;
}

.security-link {
    color: var(--accent);
    opacity: 0.7;
}

.security-link:hover {
    opacity: 1;
}

/* Responsive */
@media (max-width: 992px) {
    .services-grid {
        grid-template-columns: repeat(2, minmax(250px, 1fr));
    }
}

@media (max-width: 768px) {
    .nav {
        gap: 1rem;
    }

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

    .contact-links {
        flex-direction: column;
        align-items: center;
    }
}

@media (max-width: 480px) {
    .header {
        padding: 0 1rem;
    }

    .nav {
        gap: 0.75rem;
    }

    .nav a {
        font-size: 0.875rem;
    }

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

    .services,
    .about,
    .contacts {
        padding: 4rem 1.25rem;
    }
}