/* ============================================
   CSS Custom Properties
   ============================================ */
:root {
    --color-primary: #1a3a5c;
    --color-primary-light: #2c5680;
    --color-accent: #228ae6;
    --color-accent-light: #4ba3f5;
    --color-accent-dark: #1971c2;
    --color-text: #2c2c2c;
    --color-text-light: #6b7280;
    --color-bg: #ffffff;
    --color-bg-alt: #f5fafd;
    --color-bg-dark: #15233a;
    --color-border: #e2e8f0;
    --color-white: #ffffff;

    --font-main: 'Roboto', 'Segoe UI', -apple-system, BlinkMacSystemFont, sans-serif;

    --radius-sm: 8px;
    --radius: 14px;
    --radius-lg: 20px;

    --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.06);
    --shadow-md: 0 6px 20px rgba(0, 0, 0, 0.08);
    --shadow-lg: 0 12px 32px rgba(0, 0, 0, 0.12);
    --shadow-accent: 0 8px 24px rgba(34, 138, 230, 0.25);

    --gradient-accent: linear-gradient(135deg, #228ae6 0%, #1971c2 100%);
    --gradient-primary: linear-gradient(160deg, #1a3a5c 0%, #15233a 100%);

    --transition: all 0.3s ease;
    --transition-fast: all 0.2s ease;
    --container-width: 1140px;
    --section-padding: 90px 0;
    --header-height: 70px;
}

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

html {
    scroll-behavior: smooth;
    scroll-padding-top: var(--header-height);
    font-size: 16px;
}

body {
    font-family: var(--font-main);
    color: var(--color-text);
    background: var(--color-bg);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

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

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

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

ul {
    list-style: none;
}

.container {
    width: 100%;
    max-width: var(--container-width);
    margin: 0 auto;
    padding: 0 20px;
}

/* ============================================
   Sections
   ============================================ */
.section {
    padding: var(--section-padding);
}

.section__title {
    font-size: 2rem;
    font-weight: 700;
    color: var(--color-primary);
    text-align: center;
    margin-bottom: 50px;
    position: relative;
}

.section__title::after {
    content: '';
    display: block;
    width: 60px;
    height: 4px;
    background: var(--gradient-accent);
    border-radius: 2px;
    margin: 15px auto 0;
}

/* ============================================
   Header
   ============================================ */
.header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    background: rgba(255, 255, 255, 0.98);
    border-bottom: 1px solid var(--color-border);
    transition: var(--transition);
}

.header.scrolled {
    box-shadow: var(--shadow-md);
}

.header__container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 70px;
}

.header__logo {
    display: flex;
    align-items: center;
}

.header__logo-img {
    height: 50px;
    width: auto;
}

.header__nav-list {
    display: flex;
    gap: 30px;
}

.header__nav-link {
    font-size: 0.95rem;
    font-weight: 500;
    color: var(--color-text);
    position: relative;
    padding: 5px 0;
}

.header__nav-link::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--color-accent);
    transition: var(--transition);
}

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

.header__nav-link:hover::after {
    width: 100%;
}

.header__nav-link.active {
    color: var(--color-accent);
}

.header__nav-link.active::after {
    width: 100%;
}

.header__burger {
    display: none;
    flex-direction: column;
    justify-content: center;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 8px;
}

.header__burger span {
    display: block;
    width: 24px;
    height: 2px;
    background: var(--color-primary);
    border-radius: 2px;
    transition: var(--transition);
}

.header__burger.active span:nth-child(1) {
    transform: rotate(45deg) translate(5px, 5px);
}

.header__burger.active span:nth-child(2) {
    opacity: 0;
}

.header__burger.active span:nth-child(3) {
    transform: rotate(-45deg) translate(5px, -5px);
}

/* ============================================
   Hero
   ============================================ */
.hero {
    position: relative;
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    overflow: hidden;
}

.hero__bg {
    position: absolute;
    inset: 0;
    background-size: cover;
    background-position: center;
    background-repeat: no-repeat;
}

.hero__overlay {
    position: absolute;
    inset: 0;
    background: linear-gradient(135deg, rgba(26, 58, 92, 0.85) 0%, rgba(34, 138, 230, 0.7) 100%);
    z-index: 1;
}

.hero__content {
    position: relative;
    z-index: 2;
    text-align: center;
    padding: 50px 30px;
    max-width: 800px;
}

.hero__title {
    font-size: 3.2rem;
    font-weight: 800;
    color: var(--color-white);
    line-height: 1.15;
    margin-bottom: 16px;
    text-shadow: 0 4px 20px rgba(0, 0, 0, 0.3);
}

.hero__subtitle {
    font-size: 1.25rem;
    font-weight: 400;
    color: rgba(255, 255, 255, 0.9);
    line-height: 1.6;
    margin-bottom: 30px;
    max-width: 650px;
    margin-left: auto;
    margin-right: auto;
}

.hero__arrow {
    position: absolute;
    bottom: 30px;
    left: 50%;
    transform: translateX(-50%);
    z-index: 2;
}

.hero__arrow a {
    color: #ffffff;
    display: block;
}

.hero__arrow svg {
    width: 40px;
    height: 40px;
    animation: bounce 2s infinite;
}

@keyframes bounce {
    0%, 20%, 50%, 80%, 100% {
        transform: translateY(0);
    }
    40% {
        transform: translateY(-10px);
    }
    60% {
        transform: translateY(-5px);
    }
}

/* ============================================
   Counters
   ============================================ */
.counters {
    background: var(--color-bg-alt);
}

.counters__grid {
    display: grid;
    grid-template-columns: repeat(5, 1fr);
    gap: 24px;
    text-align: center;
}

.counter-card {
    padding: 36px 20px;
    background: var(--color-bg);
    border-radius: var(--radius);
    box-shadow: var(--shadow-sm);
    transition: var(--transition);
}

.counter-card:hover {
    transform: translateY(-6px);
    box-shadow: var(--shadow-lg);
}

.counter-card__number {
    display: block;
    font-size: 3rem;
    font-weight: 700;
    color: var(--color-accent);
    margin-bottom: 8px;
    background: var(--gradient-accent);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.counter-card__label {
    font-size: 0.9rem;
    color: var(--color-text-light);
    line-height: 1.5;
    font-weight: 500;
}

/* ============================================
   About
   ============================================ */
.about {
    background: var(--color-bg);
}

.about__content {
    max-width: 900px;
    margin: 0 auto;
}

.about__text {
    text-align: center;
    margin-bottom: 40px;
    font-size: 1.05rem;
    line-height: 1.8;
    color: var(--color-text-light);
}

.about__text p {
    margin-bottom: 15px;
}

.about__cards {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 24px;
    margin-bottom: 50px;
}

.about__card {
    background: var(--color-bg);
    border-radius: var(--radius);
    padding: 32px 28px;
    text-align: center;
    box-shadow: var(--shadow-sm);
    transition: var(--transition);
}

.about__card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
}

.about__card-icon {
    font-size: 3rem;
    margin-bottom: 16px;
}

.about__card-title {
    font-size: 1.2rem;
    font-weight: 700;
    color: var(--color-primary);
    margin-bottom: 12px;
}

.about__card-text {
    font-size: 0.95rem;
    line-height: 1.7;
    color: var(--color-text-light);
}

.about__images {
    display: flex;
    justify-content: center;
    align-items: flex-end;
    gap: 20px;
    margin-top: 40px;
}

.about__img {
    border-radius: var(--radius);
    box-shadow: var(--shadow-md);
    transition: var(--transition);
}

.about__img:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
}

.about__img--left {
    width: 400px;
    height: 275px;
    object-fit: cover;
}

.about__img--center {
    width: 500px;
    height: 325px;
    object-fit: cover;
    z-index: 1;
}

.about__img--right {
    width: 400px;
    height: 275px;
    object-fit: cover;
}

/* ============================================
   ExpertISA
   ============================================ */
.expertisa {
    background: var(--color-bg-alt);
}

.expertisa__lead {
    text-align: center;
    font-size: 1.15rem;
    line-height: 1.8;
    max-width: 850px;
    margin: -20px auto 50px;
    color: var(--color-text-light);
}

.expertisa__content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 50px;
    align-items: start;
}

.expertisa__section-title {
    font-size: 1.3rem;
    font-weight: 700;
    margin-bottom: 12px;
    color: var(--color-primary);
}

.expertisa__section-text {
    font-size: 1rem;
    line-height: 1.7;
    margin-bottom: 30px;
    color: var(--color-text-light);
}

.expertisa__features {
    display: grid;
    gap: 20px;
    margin: 30px 0;
}

.expertisa__feature {
    background: var(--color-bg);
    border-radius: var(--radius);
    padding: 24px;
    box-shadow: var(--shadow-sm);
    transition: var(--transition);
    border-left: 4px solid var(--color-accent);
}

.expertisa__feature:hover {
    transform: translateX(4px);
    box-shadow: var(--shadow-md);
}

.expertisa__feature-icon {
    font-size: 2rem;
    margin-bottom: 12px;
}

.expertisa__feature-title {
    font-size: 1.05rem;
    font-weight: 700;
    color: var(--color-primary);
    margin-bottom: 8px;
}

.expertisa__feature-text {
    font-size: 0.92rem;
    line-height: 1.65;
    color: var(--color-text-light);
}

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

.btn {
    display: inline-block;
    padding: 12px 28px;
    border-radius: 50px;
    font-weight: 600;
    text-transform: uppercase;
    font-size: 0.85rem;
    transition: var(--transition);
    letter-spacing: 0.5px;
}

.btn--blue {
    background: var(--gradient-accent);
    color: var(--color-white);
    box-shadow: var(--shadow-accent);
}

.btn--blue:hover {
    transform: translateY(-2px);
    box-shadow: 0 12px 32px rgba(34, 138, 230, 0.35);
    color: var(--color-white);
}

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

.btn--white:hover {
    background: var(--color-bg-alt);
    transform: translateY(-2px);
    color: var(--color-accent-dark);
}

.expertisa__note {
    background: #fff8e6;
    border-left: 4px solid #f5a623;
    border-radius: var(--radius-sm);
    padding: 16px 20px;
    margin: 25px 0;
}

.expertisa__note p {
    font-size: 0.88rem;
    line-height: 1.6;
    color: #8a6d3b;
    margin: 0;
}

.expertisa__registry {
    display: flex;
    align-items: flex-start;
    gap: 14px;
    background: #f0fdf4;
    border: 1px solid #bbf7d0;
    border-left: 4px solid #16a34a;
    border-radius: var(--radius-sm);
    padding: 16px 20px;
    margin: 25px 0;
}

.expertisa__registry-icon {
    flex-shrink: 0;
    width: 28px;
    height: 28px;
    color: #16a34a;
    margin-top: 2px;
}

.expertisa__registry p {
    font-size: 0.95rem;
    line-height: 1.6;
    color: #166534;
    margin: 0;
}

.expertisa__stack-title,
.expertisa__docs-title {
    font-size: 1.15rem;
    font-weight: 700;
    color: var(--color-primary);
    margin: 35px 0 20px;
}

.expertisa__stack {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 12px;
}

.expertisa__stack-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 12px 16px;
    background: var(--color-bg);
    border-radius: var(--radius-sm);
    box-shadow: var(--shadow-sm);
    transition: var(--transition-fast);
}

.expertisa__stack-item:hover {
    transform: translateX(4px);
    box-shadow: var(--shadow-md);
}

.expertisa__stack-label {
    font-size: 0.85rem;
    font-weight: 600;
    color: var(--color-text-light);
}

.expertisa__stack-value {
    font-size: 0.9rem;
    font-weight: 600;
    color: var(--color-primary);
    text-align: right;
}

.expertisa__docs {
    display: flex;
    flex-wrap: wrap;
    gap: 12px;
    margin-top: 25px;
}

.expertisa__doc-link {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 10px 16px;
    background: var(--color-bg);
    border-radius: var(--radius-sm);
    font-size: 0.88rem;
    font-weight: 500;
    color: var(--color-primary);
    box-shadow: var(--shadow-sm);
    transition: var(--transition);
}

.expertisa__doc-link:hover {
    background: var(--color-accent);
    color: var(--color-white);
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

.expertisa__doc-icon {
    font-size: 1.1rem;
}

.expertisa__right {
    position: relative;
}

.expertisa__screenshot-wrapper {
    position: relative;
    padding: 20px;
}

.screenshot-offset {
    position: absolute;
    top: -10px;
    left: -10px;
    right: -10px;
    bottom: -10px;
    background: #ffffff;
    border-radius: var(--radius);
    box-shadow: var(--shadow-lg);
    z-index: 0;
}

.expertisa__screenshot {
    position: relative;
    z-index: 1;
    border-radius: var(--radius);
    box-shadow: var(--shadow-md);
}

/* ============================================
   Contacts
   ============================================ */
.contacts {
    background: var(--color-bg);
}

.contacts__content {
    display: grid;
    grid-template-columns: 3fr 2fr;
    gap: 40px;
    align-items: stretch;
}

.contacts__left {
    padding: 10px 0;
}

.contacts__block {
    margin-bottom: 32px;
}

.contacts__block-title {
    font-size: 1.1rem;
    font-weight: 700;
    color: var(--color-primary);
    margin-bottom: 16px;
    padding-bottom: 8px;
    border-bottom: 2px solid var(--color-border);
}

.contacts__contact {
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.contacts__contact-link {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    font-size: 1.15rem;
    font-weight: 600;
    color: var(--color-accent);
    transition: var(--transition);
}

.contacts__contact-link:hover {
    color: var(--color-accent-dark);
    transform: translateX(4px);
}

.contacts__contact-icon {
    font-size: 1.3rem;
}

.contacts__address {
    font-size: 1.05rem;
    line-height: 1.6;
    color: var(--color-text);
}

.contacts__details {
    display: flex;
    flex-direction: column;
    gap: 10px;
}

.contacts__detail-row {
    display: flex;
    gap: 12px;
    font-size: 0.95rem;
    line-height: 1.5;
}

.contacts__detail-label {
    min-width: 200px;
    font-weight: 600;
    color: var(--color-text-light);
    flex-shrink: 0;
}

.contacts__detail-value {
    color: var(--color-text);
}

.contacts__accreditation {
    background: var(--color-bg-alt);
    border-radius: var(--radius);
    padding: 18px 22px;
    margin-top: 10px;
}

.contacts__accreditation p {
    font-size: 0.9rem;
    line-height: 1.6;
    color: var(--color-text-light);
    margin-bottom: 8px;
}

.contacts__okved {
    margin-bottom: 0 !important;
}

.contacts__right {
    background: var(--gradient-primary);
    border-radius: var(--radius);
    position: relative;
    overflow: hidden;
    min-height: 300px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.contacts__right::after {
    content: '';
    position: absolute;
    inset: 0;
    background: radial-gradient(circle at 30% 30%, rgba(34, 138, 230, 0.15) 0%, transparent 60%);
}

.contacts__right-content {
    position: relative;
    z-index: 1;
    text-align: center;
    padding: 40px 30px;
}

.contacts__right-icon {
    font-size: 4rem;
    margin-bottom: 20px;
}

.contacts__right-text {
    font-size: 1.2rem;
    font-weight: 600;
    color: rgba(255, 255, 255, 0.95);
    margin-bottom: 24px;
    line-height: 1.5;
}

/* ============================================
   Footer
   ============================================ */
.footer {
    background: var(--gradient-primary);
    color: rgba(255, 255, 255, 0.75);
    padding: 50px 0 0;
}

.footer__content {
    display: grid;
    grid-template-columns: 2fr 1fr 1.5fr;
    gap: 40px;
    padding-bottom: 40px;
}

.footer__brand {
    max-width: 320px;
}

.footer__logo {
    height: 45px;
    width: auto;
    margin-bottom: 16px;
    border-radius: var(--radius-sm);
}

.footer__desc {
    font-size: 0.88rem;
    line-height: 1.6;
}

.footer__title {
    font-size: 1rem;
    font-weight: 700;
    color: var(--color-white);
    margin-bottom: 16px;
}

.footer__links ul {
    display: flex;
    flex-direction: column;
    gap: 10px;
}

.footer__links a,
.footer__contacts a {
    color: rgba(255, 255, 255, 0.75);
    font-size: 0.9rem;
    transition: var(--transition-fast);
}

.footer__links a:hover,
.footer__contacts a:hover {
    color: var(--color-accent-light);
    padding-left: 4px;
}

.footer__contacts p {
    font-size: 0.9rem;
    line-height: 1.6;
    margin-bottom: 8px;
}

.footer__bottom {
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    padding: 20px 0;
}

.footer__copy {
    text-align: center;
    font-size: 0.85rem;
}

/* ============================================
   Scroll-to-top
   ============================================ */
.scroll-top {
    position: fixed;
    bottom: 30px;
    right: 30px;
    z-index: 900;
    width: 48px;
    height: 48px;
    border: none;
    border-radius: 50%;
    background: var(--gradient-accent);
    color: var(--color-white);
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: var(--shadow-accent);
    opacity: 0;
    visibility: hidden;
    transform: translateY(20px);
    transition: var(--transition);
}

.scroll-top.visible {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}

.scroll-top:hover {
    transform: translateY(-4px);
    box-shadow: 0 12px 32px rgba(34, 138, 230, 0.4);
}

/* ============================================
   Animations
   ============================================ */
.fade-in {
    opacity: 0;
    transform: translateY(20px);
    transition: opacity 0.6s ease, transform 0.6s ease;
}

.fade-in.visible {
    opacity: 1;
    transform: translateY(0);
}

/* ============================================
   Responsive
   ============================================ */
@media (max-width: 1024px) {
    .counters__grid {
        grid-template-columns: repeat(3, 1fr);
    }
    
    .expertisa__content {
        grid-template-columns: 1fr;
    }
    
    .expertisa__right {
        order: -1;
    }
    
    .contacts__content {
        grid-template-columns: 1fr;
    }
    
    .contacts__right {
        display: none;
    }

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

    .footer__brand {
        grid-column: 1 / -1;
        max-width: 100%;
        margin-bottom: 20px;
    }
}

@media (max-width: 768px) {
    .header__nav {
        position: fixed;
        top: 70px;
        left: 0;
        right: 0;
        background: var(--color-bg);
        border-bottom: 1px solid var(--color-border);
        box-shadow: var(--shadow-lg);
        transform: translateY(-100%);
        opacity: 0;
        visibility: hidden;
        transition: var(--transition);
    }
    
    .header__nav.open {
        transform: translateY(0);
        opacity: 1;
        visibility: visible;
    }
    
    .header__nav-list {
        flex-direction: column;
        gap: 0;
    }
    
    .header__nav-link {
        display: block;
        padding: 15px 20px;
        border-bottom: 1px solid var(--color-border);
    }
    
    .header__burger {
        display: flex;
    }
    
    .section {
        padding: 60px 0;
    }

    .section__title {
        font-size: 1.6rem;
        margin-bottom: 35px;
    }

    .hero__title {
        font-size: 2.2rem;
    }

    .hero__subtitle {
        font-size: 1.05rem;
    }
    
    .hero__content {
        padding: 30px 15px;
    }
    
    .counters__grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .about__cards {
        grid-template-columns: 1fr;
    }

    .about__images {
        flex-direction: column;
        align-items: center;
    }
    
    .about__img--left,
    .about__img--center,
    .about__img--right {
        width: 100%;
        max-width: 400px;
        height: auto;
    }
    
    .expertisa__stack {
        grid-template-columns: 1fr;
    }

    .contacts__detail-row {
        flex-direction: column;
        gap: 4px;
    }

    .contacts__detail-label {
        min-width: auto;
    }

    .footer__content {
        grid-template-columns: 1fr;
        gap: 30px;
    }

    .footer__brand {
        grid-column: auto;
    }

    .scroll-top {
        bottom: 20px;
        right: 20px;
        width: 42px;
        height: 42px;
    }
}

@media (max-width: 480px) {
    .counters__grid {
        grid-template-columns: 1fr;
    }
    
    .hero__title {
        font-size: 1.6rem;
    }
}