/* === Variables === */
:root {
    --color-bg: #0f1419;
    --color-surface: #1a2332;
    --color-surface-alt: #243044;
    --color-text: #e6edf3;
    --color-text-muted: #8b9cb3;
    --color-accent: #00d4aa;
    --color-accent-hover: #00f5c4;
    --color-light-bg: #f0f4f8;
    --color-light-text: #1a2332;
    --color-border: rgba(0, 212, 170, 0.2);
    --font-main: 'Manrope', sans-serif;
    --font-mono: 'JetBrains Mono', monospace;
    --radius: 12px;
    --radius-lg: 20px;
    --shadow: 0 8px 32px rgba(0, 0, 0, 0.2);
    --transition: 0.2s ease;
}

/* === Reset & Base === */
*, *::before, *::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-main);
    font-size: 18px;
    line-height: 1.6;
    color: var(--color-text);
    background: var(--color-bg);
    min-height: 100vh;
    overflow-x: hidden;
}

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

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

img {
    max-width: 100%;
    height: auto;
}

.container {
    max-width: 1100px;
    margin: 0 auto;
    padding: 0 24px;
}

/* === Header === */
.header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 100;
    background: rgba(15, 20, 25, 0.9);
    backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--color-border);
}

.header-inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 72px;
}

.logo {
    font-weight: 800;
    font-size: 1.25rem;
    letter-spacing: -0.02em;
    color: var(--color-text);
}

.logo:hover {
    color: var(--color-accent);
}

.nav {
    display: flex;
    gap: 32px;
}

.nav a {
    color: var(--color-text-muted);
    font-weight: 500;
    font-size: 0.95rem;
}

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

.nav-toggle {
    display: none;
    width: 32px;
    height: 32px;
    background: none;
    border: none;
    cursor: pointer;
    position: relative;
}

.nav-toggle::before,
.nav-toggle::after {
    content: '';
    position: absolute;
    left: 0;
    right: 0;
    height: 2px;
    background: var(--color-text);
    transition: var(--transition);
}

.nav-toggle::before { top: 8px; }
.nav-toggle::after { bottom: 8px; }

.nav-toggle-active::before {
    transform: rotate(45deg);
    top: 15px;
}

.nav-toggle-active::after {
    transform: rotate(-45deg);
    bottom: 15px;
}

@media (max-width: 768px) {
    .nav {
        position: fixed;
        top: 72px;
        left: 0;
        right: 0;
        background: var(--color-surface);
        flex-direction: column;
        padding: 24px;
        gap: 16px;
        transform: translateY(-100%);
        opacity: 0;
        pointer-events: none;
        transition: var(--transition);
        border-bottom: 1px solid var(--color-border);
    }
    .nav-open {
        transform: translateY(0);
        opacity: 1;
        pointer-events: auto;
    }
    .nav-toggle { display: block; }
}

/* === Hero === */
.hero {
    position: relative;
    min-height: 85vh;
    display: flex;
    align-items: center;
    padding: 120px 0 80px;
}

.hero-bg {
    position: absolute;
    inset: 0;
    background: 
        radial-gradient(ellipse 80% 50% at 50% -20%, rgba(0, 212, 170, 0.15), transparent),
        linear-gradient(180deg, var(--color-bg) 0%, var(--color-surface) 100%);
    pointer-events: none;
}

.hero-inner {
    position: relative;
    z-index: 1;
}

.hero-title {
    font-size: clamp(2rem, 5vw, 3.25rem);
    font-weight: 800;
    line-height: 1.15;
    letter-spacing: -0.03em;
    margin-bottom: 24px;
    max-width: 700px;
}

.hero-subtitle {
    font-size: 1.2rem;
    color: var(--color-text-muted);
    max-width: 560px;
    margin-bottom: 40px;
}

/* === Buttons === */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 14px 28px;
    font-family: var(--font-main);
    font-size: 1rem;
    font-weight: 600;
    border-radius: var(--radius);
    border: none;
    cursor: pointer;
    transition: var(--transition);
}

.btn-primary {
    background: var(--color-accent);
    color: var(--color-bg);
}

.btn-primary:hover {
    background: var(--color-accent-hover);
    transform: translateY(-2px);
    box-shadow: 0 8px 24px rgba(0, 212, 170, 0.35);
}

/* === Sections (common) === */
.section {
    padding: 80px 0;
}

.section:nth-child(even) {
    background: var(--color-surface);
}

.section-title {
    font-size: clamp(1.75rem, 4vw, 2.25rem);
    font-weight: 800;
    letter-spacing: -0.02em;
    margin-bottom: 16px;
}

.section-intro {
    color: var(--color-text-muted);
    font-size: 1.1rem;
    max-width: 640px;
    margin-bottom: 48px;
}

/* === About === */
.section-about .about-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 24px;
}

.about-block {
    background: var(--color-surface-alt);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-lg);
    padding: 32px;
}

.about-block h3 {
    font-size: 1.15rem;
    font-weight: 700;
    margin-bottom: 12px;
    color: var(--color-accent);
}

.about-block p {
    color: var(--color-text-muted);
    font-size: 0.98rem;
}

.about-block-wide {
    grid-column: 1 / -1;
}

@media (max-width: 640px) {
    .section-about .about-grid {
        grid-template-columns: 1fr;
    }
}

/* === Services === */
.section-services {
    background: var(--color-light-bg);
    color: var(--color-light-text);
}

.section-services .section-title,
.section-services .section-intro {
    color: var(--color-light-text);
}

.section-services .section-intro {
    color: #4a5568;
}

.services-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 24px;
}

.service-card {
    background: #fff;
    border-radius: var(--radius-lg);
    padding: 32px;
    border: 1px solid #e2e8f0;
    transition: var(--transition);
}

.service-card:hover {
    border-color: var(--color-accent);
    box-shadow: var(--shadow);
}

.service-icon {
    font-size: 1.5rem;
    color: var(--color-accent);
    margin-bottom: 16px;
    font-family: var(--font-mono);
}

.service-card h3 {
    font-size: 1.2rem;
    font-weight: 700;
    margin-bottom: 12px;
    color: var(--color-light-text);
}

.service-card p {
    color: #4a5568;
    font-size: 0.95rem;
}

.section-services a {
    color: #0d9488;
}

@media (max-width: 768px) {
    .services-grid {
        grid-template-columns: 1fr;
    }
}

/* === Tech === */
.tech-blocks {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
}

.tech-block {
    background: var(--color-surface-alt);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-lg);
    padding: 28px;
}

.tech-block h3 {
    font-size: 1.1rem;
    font-weight: 700;
    margin-bottom: 12px;
    color: var(--color-accent);
}

.tech-block p {
    color: var(--color-text-muted);
    font-size: 0.95rem;
}

@media (max-width: 768px) {
    .tech-blocks {
        grid-template-columns: 1fr;
    }
}

/* === Approach === */
.approach-list {
    display: flex;
    flex-direction: column;
    gap: 24px;
}

.approach-item {
    display: flex;
    gap: 32px;
    align-items: flex-start;
    background: var(--color-surface-alt);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-lg);
    padding: 28px 32px;
}

.approach-num {
    font-family: var(--font-mono);
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--color-accent);
    flex-shrink: 0;
}

.approach-item h3 {
    font-size: 1.15rem;
    font-weight: 700;
    margin-bottom: 8px;
}

.approach-item p {
    color: var(--color-text-muted);
    font-size: 0.98rem;
}

@media (max-width: 640px) {
    .approach-item {
        flex-direction: column;
        gap: 12px;
    }
}

/* === Advantages === */
.section-advantages {
    background: var(--color-light-bg);
    color: var(--color-light-text);
}

.section-advantages .section-title {
    color: var(--color-light-text);
}

.advantages-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 24px;
}

.advantage-card {
    background: #fff;
    border-radius: var(--radius-lg);
    padding: 28px;
    border: 1px solid #e2e8f0;
    transition: var(--transition);
}

.advantage-card:hover {
    border-color: var(--color-accent);
    box-shadow: var(--shadow);
}

.advantage-card h3 {
    font-size: 1.1rem;
    font-weight: 700;
    margin-bottom: 10px;
    color: var(--color-light-text);
}

.advantage-card p {
    color: #4a5568;
    font-size: 0.92rem;
}

@media (max-width: 900px) {
    .advantages-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 480px) {
    .advantages-grid {
        grid-template-columns: 1fr;
    }
}

/* === CTA === */
.section-cta {
    text-align: center;
}

.section-cta .section-intro {
    margin-left: auto;
    margin-right: auto;
}

/* === Contacts === */
.section-contacts {
    background: var(--color-surface);
    padding: 80px 0 100px;
}

.contacts-block {
    display: flex;
    flex-wrap: wrap;
    gap: 48px 64px;
    margin-bottom: 32px;
    padding: 40px;
    background: var(--color-surface-alt);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-lg);
}

.contact-item {
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.contact-label {
    font-size: 0.85rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.08em;
    color: var(--color-text-muted);
}

.contact-value {
    font-size: 1.25rem;
    font-weight: 600;
    color: var(--color-accent);
}

.contact-value:hover {
    color: var(--color-accent-hover);
    text-decoration: underline;
}

.contacts-note {
    color: var(--color-text-muted);
    font-size: 0.95rem;
    max-width: 560px;
}

/* === Footer === */
.footer {
    padding: 24px 0;
    border-top: 1px solid var(--color-border);
    text-align: center;
}

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