:root {
    --bg: #05060b;
    --bg-alt: #0b0d15;
    --surface: #111320;
    --surface-alt: #171a28;
    --accent: #3ea6ff;
    --accent-soft: rgba(62, 166, 255, 0.18);
    --text: #f5f7ff;
    --muted: #a0a4b8;
    --border-soft: rgba(255, 255, 255, 0.06);
    --radius-lg: 18px;
    --radius-sm: 10px;
    --shadow-soft: 0 20px 40px rgba(0, 0, 0, 0.35);
}

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

html, body {
    margin: 0;
    padding: 0;
    font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
    background: radial-gradient(circle at top, #0d1220 0, #05060b 55%, #020309 100%);
    color: var(--text);
    scroll-behavior: smooth;
}

a {
    color: var(--accent);
    text-decoration: none;
}

a:hover {
    text-decoration: underline;
}

/* Layout */

.container {
    width: 100%;
    max-width: 1120px;
    margin: 0 auto;
    padding: 0 16px;
}

.section {
    padding: 80px 0;
}

.section-alt {
    padding: 80px 0;
    background: radial-gradient(circle at top left, #14182a 0, #070814 55%, #05060b 100%);
}

.section h2 {
    font-size: 30px;
    margin: 0 0 12px;
}

.section-intro {
    max-width: 720px;
    color: var(--muted);
    margin: 0 0 32px;
}

/* Header */

.site-header {
    position: sticky;
    top: 0;
    z-index: 20;
    background: linear-gradient(to bottom, rgba(5, 6, 11, 0.96), rgba(5, 6, 11, 0.86), transparent);
    backdrop-filter: blur(14px);
    border-bottom: 1px solid var(--border-soft);
}

.header-inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 10px 0;
}

.logo {
    display: flex;
    align-items: center;
    gap: 10px;
}

.logo-mark {
    width: 34px;
    height: 34px;
    border-radius: 999px;
    background: radial-gradient(circle at 30% 0, #6ad6ff, #3ea6ff 40%, #2568ff 80%);
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 700;
    color: #08101c;
    box-shadow: 0 0 24px rgba(62, 166, 255, 0.6);
}

.logo-text {
    display: flex;
    flex-direction: column;
    line-height: 1.1;
}

.logo-name {
    font-weight: 700;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    font-size: 13px;
}

.logo-tagline {
    font-size: 11px;
    color: var(--muted);
}

.main-nav {
    display: flex;
    gap: 18px;
    font-size: 14px;
}

.main-nav a {
    position: relative;
    color: var(--muted);
    text-decoration: none;
    padding-bottom: 4px;
}

.main-nav a::after {
    content: "";
    position: absolute;
    left: 0;
    bottom: 0;
    width: 0;
    height: 2px;
    border-radius: 999px;
    background: linear-gradient(90deg, #3ea6ff, #7cf5ff);
    transition: width 0.2s ease;
}

.main-nav a:hover {
    color: var(--text);
}

.main-nav a:hover::after {
    width: 100%;
}

/* Hero */

.hero {
    padding: 80px 0 60px;
}

.hero-inner {
    display: grid;
    grid-template-columns: minmax(0, 1.3fr) minmax(0, 1fr);
    gap: 40px;
    align-items: center;
}

.hero-content h1 {
    font-size: clamp(28px, 4vw, 36px);
    margin: 0 0 16px;
}

.hero-content p {
    color: var(--muted);
    margin: 0 0 18px;
}

.hero-highlights {
    list-style: none;
    padding: 0;
    margin: 0 0 24px;
    display: flex;
    flex-wrap: wrap;
    gap: 6px 12px;
}

.hero-highlights li {
    font-size: 13px;
    color: var(--muted);
    padding: 4px 10px;
    border-radius: 999px;
    border: 1px solid var(--border-soft);
    background: rgba(255, 255, 255, 0.02);
}

.btn-primary {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 9px 18px;
    border-radius: 999px;
    border: none;
    background: linear-gradient(135deg, #3ea6ff, #7cf5ff);
    color: #020309;
    font-weight: 600;
    font-size: 14px;
    box-shadow: 0 16px 32px rgba(0, 0, 0, 0.5);
    cursor: pointer;
}

.btn-primary:hover {
    text-decoration: none;
    box-shadow: 0 22px 40px rgba(0, 0, 0, 0.65);
    transform: translateY(-1px);
}

.hero-visual {
    justify-self: stretch;
}

/* Placeholders */

.image-placeholder {
    border-radius: var(--radius-lg);
    border: 1px dashed rgba(255, 255, 255, 0.25);
    background: radial-gradient(circle at top, var(--accent-soft), rgba(255, 255, 255, 0.01));
    min-height: 220px;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    padding: 18px;
    color: var(--muted);
    font-size: 13px;
}

.image-placeholder.small {
    min-height: 120px;
}

.icon-placeholder {
    width: 40px;
    height: 40px;
    border-radius: 999px;
    border: 1px solid var(--border-soft);
    background: radial-gradient(circle at 30% 0, rgba(62, 166, 255, 0.9), rgba(7, 14, 40, 1));
}

/* Two columns */

.two-columns {
    display: grid;
    gap: 32px;
    grid-template-columns: minmax(0, 1.2fr) minmax(0, 1fr);
    align-items: center;
}

.about-meta {
    margin-top: 18px;
    padding: 12px 14px;
    border-radius: var(--radius-sm);
    border: 1px solid var(--border-soft);
    background: rgba(7, 10, 25, 0.75);
    color: var(--muted);
    font-size: 13px;
}

/* Cards */

.cards-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
    gap: 18px;
}

.card {
    background: var(--surface);
    border-radius: var(--radius-lg);
    padding: 18px 18px 16px;
    border: 1px solid var(--border-soft);
    box-shadow: var(--shadow-soft);
}

.card h3 {
    margin: 10px 0 6px;
    font-size: 17px;
}

.card p {
    margin: 0;
    color: var(--muted);
    font-size: 14px;
}

/* Projects */

.projects-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
    gap: 20px;
}

.project-card {
    background: var(--surface);
    border-radius: var(--radius-lg);
    border: 1px solid var(--border-soft);
    box-shadow: var(--shadow-soft);
    overflow: hidden;
    display: flex;
    flex-direction: column;
}

.project-image {
    border-radius: var(--radius-lg) var(--radius-lg) 0 0;
    border-bottom: 1px solid var(--border-soft);
}

.project-body {
    padding: 14px 16px 16px;
}

.project-body h3 {
    margin: 0 0 6px;
    font-size: 16px;
}

.project-body p {
    margin: 0;
    font-size: 14px;
    color: var(--muted);
}

/* Tech section */

.tech-columns {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
    gap: 22px;
    margin-top: 10px;
}

.tech-columns h3 {
    margin-bottom: 6px;
    font-size: 16px;
}

.tech-columns ul {
    list-style: none;
    padding-left: 0;
    margin: 0;
}

.tech-columns li {
    font-size: 14px;
    color: var(--muted);
    padding-left: 16px;
    position: relative;
    margin-bottom: 4px;
}

.tech-columns li::before {
    content: "•";
    position: absolute;
    left: 0;
    top: 0;
    color: var(--accent);
}

/* Contact */

.contact-grid {
    display: grid;
    grid-template-columns: minmax(0, 1.15fr) minmax(0, 1fr);
    gap: 30px;
}

.contact-list {
    list-style: none;
    padding-left: 0;
    margin: 18px 0 0;
    color: var(--muted);
    font-size: 14px;
}

.contact-list li + li {
    margin-top: 4px;
}

.contact-box {
    background: var(--surface);
    border-radius: var(--radius-lg);
    border: 1px solid var(--border-soft);
    padding: 18px 18px 14px;
    box-shadow: var(--shadow-soft);
}

.contact-box h3 {
    margin: 0 0 8px;
    font-size: 16px;
}

.contact-box p {
    margin: 0 0 12px;
    color: var(--muted);
    font-size: 14px;
}

/* Footer */

.site-footer {
    border-top: 1px solid var(--border-soft);
    padding: 14px 0 18px;
    background: rgba(2, 3, 9, 0.96);
}

.footer-inner {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
    font-size: 12px;
    color: var(--muted);
    justify-content: space-between;
}

.footer-right a {
    color: var(--muted);
}

.footer-right a:hover {
    color: var(--accent);
}

/* Responsive */

@media (max-width: 880px) {
    .hero-inner,
    .two-columns,
    .contact-grid {
        grid-template-columns: minmax(0, 1fr);
    }

    .hero {
        padding-top: 70px;
    }

    .main-nav {
        display: none; /* позже можно сделать бургер-меню */
    }

    .header-inner {
        padding: 8px 0;
    }
}

@media (max-width: 520px) {
    .section,
    .section-alt {
        padding: 60px 0;
    }

    .cards-grid {
        grid-template-columns: minmax(0, 1fr);
    }

    .projects-grid {
        grid-template-columns: minmax(0, 1fr);
    }
}