/* ==========================================================================
   ООО «Томские сорбционные технологии» — Design System & Stylesheet
   ========================================================================== */

/* ==========================================================================
   0. Local Inter Fonts (Self-hosted, Zero External Requests)
   ========================================================================== */

/* Variable font weights (400 - 800) */
@font-face {
  font-family: 'Inter';
  font-style: normal;
  font-weight: 400 800;
  font-display: swap;
  src: url('../fonts/inter-cyrillic-ext.woff2') format('woff2');
  unicode-range: U+0460-052F, U+1C80-1C8A, U+20B4, U+2DE0-2DFF, U+A640-A69F, U+FE2E-FE2F;
}

@font-face {
  font-family: 'Inter';
  font-style: normal;
  font-weight: 400 800;
  font-display: swap;
  src: url('../fonts/inter-cyrillic.woff2') format('woff2');
  unicode-range: U+0301, U+0400-045F, U+0490-0491, U+04B0-04B1, U+2116;
}

@font-face {
  font-family: 'Inter';
  font-style: normal;
  font-weight: 400 800;
  font-display: swap;
  src: url('../fonts/inter-greek-ext.woff2') format('woff2');
  unicode-range: U+1F00-1FFF;
}

@font-face {
  font-family: 'Inter';
  font-style: normal;
  font-weight: 400 800;
  font-display: swap;
  src: url('../fonts/inter-greek.woff2') format('woff2');
  unicode-range: U+0370-0377, U+037A-037F, U+0384-038A, U+038C, U+038E-03A1, U+03A3-03FF;
}

@font-face {
  font-family: 'Inter';
  font-style: normal;
  font-weight: 400 800;
  font-display: swap;
  src: url('../fonts/inter-vietnamese.woff2') format('woff2');
  unicode-range: U+0102-0103, U+0110-0111, U+0128-0129, U+0168-0169, U+01A0-01A1, U+01AF-01B0, U+0300-0301, U+0303-0304, U+0308-0309, U+0323, U+0329, U+1EA0-1EF9, U+20AB;
}

@font-face {
  font-family: 'Inter';
  font-style: normal;
  font-weight: 400 800;
  font-display: swap;
  src: url('../fonts/inter-latin-ext.woff2') format('woff2');
  unicode-range: U+0100-02BA, U+02BD-02C5, U+02C7-02CC, U+02CE-02D7, U+02DD-02FF, U+0304, U+0308, U+0329, U+1D00-1DBF, U+1E00-1E9F, U+1EF2-1EFF, U+2020, U+20A0-20AB, U+20AD-20C0, U+2113, U+2C60-2C7F, U+A720-A7FF;
}

@font-face {
  font-family: 'Inter';
  font-style: normal;
  font-weight: 400 800;
  font-display: swap;
  src: url('../fonts/inter-latin.woff2') format('woff2');
  unicode-range: U+0000-00FF, U+0131, U+0152-0153, U+02BB-02BC, U+02C6, U+02DA, U+02DC, U+0304, U+0308, U+0329, U+2000-206F, U+20AC, U+2122, U+2191, U+2193, U+2212, U+2215, U+FEFF, U+FFFD;
}

/* Explicit weight fallbacks for older browser compatibility */
@font-face {
  font-family: 'Inter';
  font-style: normal;
  font-weight: 400;
  font-display: swap;
  src: url('../fonts/inter-cyrillic.woff2') format('woff2');
  unicode-range: U+0301, U+0400-045F, U+0490-0491, U+04B0-04B1, U+2116;
}
@font-face {
  font-family: 'Inter';
  font-style: normal;
  font-weight: 400;
  font-display: swap;
  src: url('../fonts/inter-latin.woff2') format('woff2');
  unicode-range: U+0000-00FF, U+0131, U+0152-0153, U+02BB-02BC, U+02C6, U+02DA, U+02DC, U+0304, U+0308, U+0329, U+2000-206F, U+20AC, U+2122, U+2191, U+2193, U+2212, U+2215, U+FEFF, U+FFFD;
}
@font-face {
  font-family: 'Inter';
  font-style: normal;
  font-weight: 500;
  font-display: swap;
  src: url('../fonts/inter-cyrillic.woff2') format('woff2');
  unicode-range: U+0301, U+0400-045F, U+0490-0491, U+04B0-04B1, U+2116;
}
@font-face {
  font-family: 'Inter';
  font-style: normal;
  font-weight: 500;
  font-display: swap;
  src: url('../fonts/inter-latin.woff2') format('woff2');
  unicode-range: U+0000-00FF, U+0131, U+0152-0153, U+02BB-02BC, U+02C6, U+02DA, U+02DC, U+0304, U+0308, U+0329, U+2000-206F, U+20AC, U+2122, U+2191, U+2193, U+2212, U+2215, U+FEFF, U+FFFD;
}
@font-face {
  font-family: 'Inter';
  font-style: normal;
  font-weight: 600;
  font-display: swap;
  src: url('../fonts/inter-cyrillic.woff2') format('woff2');
  unicode-range: U+0301, U+0400-045F, U+0490-0491, U+04B0-04B1, U+2116;
}
@font-face {
  font-family: 'Inter';
  font-style: normal;
  font-weight: 600;
  font-display: swap;
  src: url('../fonts/inter-latin.woff2') format('woff2');
  unicode-range: U+0000-00FF, U+0131, U+0152-0153, U+02BB-02BC, U+02C6, U+02DA, U+02DC, U+0304, U+0308, U+0329, U+2000-206F, U+20AC, U+2122, U+2191, U+2193, U+2212, U+2215, U+FEFF, U+FFFD;
}
@font-face {
  font-family: 'Inter';
  font-style: normal;
  font-weight: 700;
  font-display: swap;
  src: url('../fonts/inter-cyrillic.woff2') format('woff2');
  unicode-range: U+0301, U+0400-045F, U+0490-0491, U+04B0-04B1, U+2116;
}
@font-face {
  font-family: 'Inter';
  font-style: normal;
  font-weight: 700;
  font-display: swap;
  src: url('../fonts/inter-latin.woff2') format('woff2');
  unicode-range: U+0000-00FF, U+0131, U+0152-0153, U+02BB-02BC, U+02C6, U+02DA, U+02DC, U+0304, U+0308, U+0329, U+2000-206F, U+20AC, U+2122, U+2191, U+2193, U+2212, U+2215, U+FEFF, U+FFFD;
}
@font-face {
  font-family: 'Inter';
  font-style: normal;
  font-weight: 800;
  font-display: swap;
  src: url('../fonts/inter-cyrillic.woff2') format('woff2');
  unicode-range: U+0301, U+0400-045F, U+0490-0491, U+04B0-04B1, U+2116;
}
@font-face {
  font-family: 'Inter';
  font-style: normal;
  font-weight: 800;
  font-display: swap;
  src: url('../fonts/inter-latin.woff2') format('woff2');
  unicode-range: U+0000-00FF, U+0131, U+0152-0153, U+02BB-02BC, U+02C6, U+02DA, U+02DC, U+0304, U+0308, U+0329, U+2000-206F, U+20AC, U+2122, U+2191, U+2193, U+2212, U+2215, U+FEFF, U+FFFD;
}

:root {
  /* Color Palette */
  --bg-primary: #0a0f1d;
  --bg-surface: #111827;
  --bg-surface-elevated: #1f293d;
  --bg-surface-alt: #162032;
  --bg-light: #f8fafc;
  --bg-light-surface: #ffffff;
  
  --primary: #2563eb;
  --primary-hover: #1d4ed8;
  --primary-glow: rgba(37, 99, 235, 0.35);
  --accent: #0284c7;
  --accent-light: #38bdf8;
  --accent-glow: rgba(56, 189, 248, 0.25);
  
  --text-main: #f1f5f9;
  --text-muted: #94a3b8;
  --text-dim: #64748b;
  --text-dark: #0f172a;
  --text-dark-muted: #475569;

  --border-subtle: rgba(255, 255, 255, 0.08);
  --border-light: rgba(255, 255, 255, 0.15);
  --border-glow: rgba(56, 189, 248, 0.4);

  --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.25);
  --shadow-md: 0 8px 24px rgba(0, 0, 0, 0.35);
  --shadow-lg: 0 16px 40px rgba(0, 0, 0, 0.45);
  --shadow-glow: 0 0 25px rgba(37, 99, 235, 0.25);

  --radius-sm: 8px;
  --radius-md: 14px;
  --radius-lg: 20px;
  --radius-full: 9999px;

  --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Helvetica, Arial, sans-serif;
  --transition-fast: 0.2s cubic-bezier(0.4, 0, 0.2, 1);
  --transition-base: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  --transition-smooth: 0.5s cubic-bezier(0.16, 1, 0.3, 1);
}

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

html {
  scroll-behavior: smooth;
  scroll-padding-top: 80px;
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: var(--font-sans);
  background-color: var(--bg-primary);
  color: var(--text-main);
  line-height: 1.6;
  overflow-x: hidden;
}

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

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

ul {
  list-style: none;
}

button {
  font-family: inherit;
  cursor: pointer;
  border: none;
  background: none;
}

/* Layout Utilities */
.container {
  width: 100%;
  max-width: 1240px;
  margin: 0 auto;
  padding: 0 24px;
}

.section {
  padding: 100px 0;
  position: relative;
}

@media (max-width: 768px) {
  .section {
    padding: 60px 0;
  }
}

.section-header {
  text-align: center;
  max-width: 820px;
  margin: 0 auto 60px;
}

.section-tag {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 16px;
  border-radius: var(--radius-full);
  background: rgba(37, 99, 235, 0.12);
  border: 1px solid rgba(56, 189, 248, 0.25);
  color: var(--accent-light);
  font-size: 0.875rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: 16px;
}

.section-title {
  font-size: clamp(2rem, 3.5vw, 2.75rem);
  font-weight: 700;
  line-height: 1.25;
  color: #ffffff;
  margin-bottom: 16px;
  letter-spacing: -0.02em;
}

.section-descr {
  font-size: clamp(1rem, 1.5vw, 1.18rem);
  color: var(--text-muted);
  line-height: 1.65;
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  padding: 14px 28px;
  font-size: 1rem;
  font-weight: 600;
  border-radius: var(--radius-full);
  transition: var(--transition-base);
  text-align: center;
  white-space: nowrap;
}

.btn-primary {
  background: linear-gradient(135deg, #0284c7 0%, #1d4ed8 100%);
  color: #ffffff;
  box-shadow: 0 4px 20px var(--primary-glow);
  border: 1px solid rgba(255, 255, 255, 0.2);
}

.btn-primary:hover {
  background: linear-gradient(135deg, #0369a1 0%, #1e40af 100%);
  box-shadow: 0 6px 28px rgba(37, 99, 235, 0.45);
  transform: translateY(-2px);
}

.btn-secondary {
  background: rgba(255, 255, 255, 0.06);
  color: var(--text-main);
  border: 1px solid var(--border-light);
  backdrop-filter: blur(8px);
}

.btn-secondary:hover {
  background: rgba(255, 255, 255, 0.12);
  border-color: rgba(255, 255, 255, 0.3);
  transform: translateY(-2px);
}

.btn-sm {
  padding: 8px 18px;
  font-size: 0.875rem;
}

/* ==========================================================================
   1. Header / Navbar
   ========================================================================== */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(10, 15, 29, 0.88);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--border-subtle);
  transition: var(--transition-fast);
}

.site-header .container {
  max-width: 1360px;
  padding: 0 20px;
}

.navbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 80px;
  gap: 16px;
  width: 100%;
}

.nav-brand {
  display: flex;
  align-items: center;
  gap: 10px;
  font-weight: 700;
  font-size: 1.02rem;
  color: #ffffff;
  letter-spacing: -0.01em;
  white-space: nowrap;
  flex-shrink: 0;
}

.brand-title {
  display: inline-flex;
  align-items: center;
  white-space: nowrap;
}

.brand-full {
  display: none;
}

.brand-short {
  display: inline;
}

@media (min-width: 1440px) {
  .brand-full {
    display: inline;
  }
  .brand-short {
    display: none;
  }
}

.brand-icon {
  width: 36px;
  height: 36px;
  flex-shrink: 0;
}

.nav-menu {
  display: flex;
  align-items: center;
  gap: clamp(8px, 1.2vw, 18px);
  white-space: nowrap;
}

.nav-link {
  font-size: 0.88rem;
  font-weight: 500;
  color: var(--text-muted);
  position: relative;
  padding: 6px 2px;
  white-space: nowrap;
  transition: var(--transition-fast);
}

.nav-link:hover,
.nav-link.active {
  color: #ffffff;
}

.nav-link::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--accent-light);
  transition: width var(--transition-fast);
  border-radius: 2px;
}

.nav-link:hover::after,
.nav-link.active::after {
  width: 100%;
}

.nav-cta {
  display: flex;
  align-items: center;
  flex-shrink: 0;
  white-space: nowrap;
}

.nav-cta .btn {
  padding: 8px 16px;
  font-size: 0.86rem;
}

.burger-btn {
  display: none;
  flex-direction: column;
  justify-content: space-between;
  width: 28px;
  height: 20px;
  background: transparent;
  cursor: pointer;
  z-index: 102;
}

.burger-btn span {
  display: block;
  height: 2px;
  width: 100%;
  background: #ffffff;
  border-radius: 2px;
  transition: var(--transition-base);
}

.burger-btn.open span:nth-child(1) {
  transform: translateY(9px) rotate(45deg);
}

.burger-btn.open span:nth-child(2) {
  opacity: 0;
}

.burger-btn.open span:nth-child(3) {
  transform: translateY(-9px) rotate(-45deg);
}

@media (max-width: 1140px) {
  .burger-btn {
    display: flex;
  }

  .nav-menu {
    position: fixed;
    top: 80px;
    left: 0;
    width: 100%;
    height: calc(100vh - 80px);
    background: rgba(10, 15, 29, 0.98);
    backdrop-filter: blur(20px);
    flex-direction: column;
    align-items: center;
    justify-content: flex-start;
    padding-top: 40px;
    gap: 26px;
    transform: translateX(100%);
    transition: transform var(--transition-smooth);
    z-index: 101;
    overflow-y: auto;
  }

  .nav-menu.open {
    transform: translateX(0);
  }

  .nav-menu .nav-link {
    font-size: 1.25rem;
  }

  .nav-cta {
    display: none;
  }

  .nav-menu-cta {
    display: block;
    margin-top: 10px;
  }
}

@media (min-width: 1141px) {
  .nav-menu-cta {
    display: none;
  }
}

/* ==========================================================================
   2. Grant / Startup Banner
   ========================================================================== */
.grant-banner {
  background: linear-gradient(90deg, #1e293b 0%, #0f172a 100%);
  border-bottom: 1px solid var(--border-subtle);
  padding: 16px 0;
}

.grant-banner__content {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 28px;
}

.grant-banner__logo {
  max-width: 240px;
  height: auto;
  filter: drop-shadow(0 2px 4px rgba(0, 0, 0, 0.4));
  flex-shrink: 0;
}

.grant-banner__text {
  font-size: 0.93rem;
  line-height: 1.5;
  color: #cbd5e1;
  max-width: 780px;
  border-left: 2px solid var(--accent);
  padding-left: 18px;
}

.grant-banner__text strong {
  color: #ffffff;
}

@media (max-width: 768px) {
  .grant-banner__content {
    flex-direction: column;
    text-align: center;
    gap: 14px;
  }

  .grant-banner__text {
    border-left: none;
    border-top: 2px solid var(--accent);
    padding-left: 0;
    padding-top: 12px;
    font-size: 0.875rem;
  }
}

/* ==========================================================================
   3. Hero Section
   ========================================================================== */
.hero-section {
  position: relative;
  padding: 110px 0 100px;
  overflow: hidden;
  background: radial-gradient(circle at 50% 10%, rgba(37, 99, 235, 0.15) 0%, transparent 65%);
}

.hero-wrapper {
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 8px 20px;
  border-radius: var(--radius-full);
  background: rgba(37, 99, 235, 0.12);
  border: 1px solid rgba(56, 189, 248, 0.3);
  color: var(--accent-light);
  font-size: 0.9rem;
  font-weight: 600;
  margin-bottom: 24px;
}

.hero-title {
  font-size: clamp(2.2rem, 4.5vw, 3.8rem);
  font-weight: 800;
  line-height: 1.18;
  letter-spacing: -0.03em;
  color: #ffffff;
  max-width: 960px;
  margin-bottom: 24px;
}

.hero-descr {
  font-size: clamp(1.05rem, 1.8vw, 1.28rem);
  color: #cbd5e1;
  max-width: 820px;
  margin-bottom: 38px;
  line-height: 1.7;
}

.hero-actions {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 16px;
  margin-bottom: 60px;
  flex-wrap: wrap;
}

.hero-image-container {
  width: 100%;
  max-width: 1080px;
  position: relative;
  border-radius: var(--radius-lg);
  overflow: hidden;
  border: 1px solid var(--border-light);
  box-shadow: 0 25px 60px -15px rgba(0, 0, 0, 0.7), var(--shadow-glow);
}

.hero-image {
  width: 100%;
  max-height: 520px;
  object-fit: cover;
  transition: transform 0.8s ease;
}

.hero-image-container:hover .hero-image {
  transform: scale(1.02);
}

.hero-overlay-tags {
  position: absolute;
  bottom: 24px;
  left: 24px;
  right: 24px;
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  z-index: 2;
}

.hero-tag {
  background: rgba(15, 23, 42, 0.85);
  backdrop-filter: blur(10px);
  border: 1px solid var(--border-light);
  color: #ffffff;
  padding: 8px 16px;
  border-radius: var(--radius-full);
  font-size: 0.85rem;
  font-weight: 500;
}

/* ==========================================================================
   4. Products Section (Наши работы)
   ========================================================================== */
.products-section {
  background: var(--bg-surface);
  border-top: 1px solid var(--border-subtle);
  border-bottom: 1px solid var(--border-subtle);
}

.products-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 32px;
}

.product-card {
  background: var(--bg-surface-elevated);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  overflow: hidden;
  display: flex;
  flex-direction: column;
  transition: var(--transition-base);
  box-shadow: var(--shadow-md);
  cursor: pointer;
}

.product-card:hover {
  transform: translateY(-6px);
  border-color: var(--border-glow);
  box-shadow: 0 20px 40px rgba(0, 0, 0, 0.5), 0 0 20px rgba(56, 189, 248, 0.15);
}

.product-card__header {
  padding: 24px 28px;
  border-bottom: 1px solid var(--border-subtle);
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.product-card__title {
  font-size: 1.45rem;
  font-weight: 700;
  color: #ffffff;
  letter-spacing: -0.01em;
}

.product-card__zoom-hint {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: 0.8rem;
  color: var(--accent-light);
  opacity: 0.85;
}

.product-card__media {
  position: relative;
  aspect-ratio: 4 / 3;
  overflow: hidden;
  background: #0b1120;
}

.product-card__img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.6s cubic-bezier(0.2, 1, 0.3, 1);
}

.product-card:hover .product-card__img {
  transform: scale(1.05);
}

.product-card__body {
  padding: 24px 28px;
  display: flex;
  flex-direction: column;
  gap: 16px;
  flex: 1;
}

.product-card__descr {
  font-size: 0.98rem;
  color: var(--text-muted);
  line-height: 1.6;
}

.product-card__tags {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: auto;
}

.badge {
  display: inline-block;
  padding: 4px 12px;
  border-radius: var(--radius-full);
  font-size: 0.78rem;
  font-weight: 600;
  background: rgba(255, 255, 255, 0.06);
  color: #cbd5e1;
  border: 1px solid var(--border-subtle);
}

.badge-trl {
  background: rgba(16, 185, 129, 0.15);
  color: #34d399;
  border-color: rgba(16, 185, 129, 0.3);
}

/* Product Detail & Specs */
.product-detail-btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  margin-top: 14px;
  padding: 10px 20px;
  font-size: 0.88rem;
  font-weight: 600;
  border-radius: var(--radius-md);
  background: rgba(37, 99, 235, 0.15);
  color: var(--accent-light);
  border: 1px solid rgba(56, 189, 248, 0.25);
  transition: var(--transition-fast);
  cursor: pointer;
  width: fit-content;
}

.product-detail-btn:hover {
  background: rgba(37, 99, 235, 0.3);
  border-color: var(--accent-light);
  color: #ffffff;
}

.product-specs-container {
  margin-top: 20px;
  padding-top: 20px;
  border-top: 1px solid var(--border-subtle);
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.product-meta-block {
  margin-bottom: 4px;
}

.product-meta-title {
  font-size: 0.85rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--accent-light);
  margin-bottom: 6px;
  display: flex;
  align-items: center;
  gap: 6px;
}

.product-meta-text {
  font-size: 0.92rem;
  color: #cbd5e1;
  line-height: 1.55;
}

.specs-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 12px;
  margin-top: 8px;
}

@media (max-width: 600px) {
  .specs-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

.product-card_featured {
  display: grid;
  grid-template-columns: 440px 1fr;
  max-width: 1140px;
  margin: 0 auto;
}

@media (max-width: 992px) {
  .product-card_featured {
    grid-template-columns: 1fr;
  }
}

.product-card_featured .product-card__media {
  aspect-ratio: auto;
  min-height: 380px;
}

.product-card_featured .product-card__body {
  padding: 36px 40px;
}

.spec-card {
  background: rgba(10, 15, 29, 0.7);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-sm);
  padding: 12px 14px;
  display: flex;
  flex-direction: column;
  transition: var(--transition-fast);
}

.spec-card:hover {
  border-color: rgba(56, 189, 248, 0.35);
  background: rgba(15, 23, 42, 0.9);
}

.spec-val {
  font-size: 1.15rem;
  font-weight: 700;
  color: #ffffff;
  letter-spacing: -0.01em;
}

.spec-label {
  font-size: 0.75rem;
  color: var(--text-dim);
  margin-top: 2px;
  line-height: 1.3;
}

/* ==========================================================================
   5. Core Technology & Services (Основная технология / О нас)
   ========================================================================== */
.tech-section {
  position: relative;
  background: var(--bg-primary);
}

.tech-cards-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 32px;
  margin-top: 40px;
}

@media (max-width: 860px) {
  .tech-cards-grid {
    grid-template-columns: 1fr;
  }
}

.tech-card {
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  overflow: hidden;
  transition: var(--transition-base);
  box-shadow: var(--shadow-md);
  display: flex;
  flex-direction: column;
}

.tech-card:hover {
  transform: translateY(-5px);
  border-color: rgba(56, 189, 248, 0.3);
  box-shadow: 0 16px 36px rgba(0, 0, 0, 0.45);
}

.tech-card__media {
  position: relative;
  aspect-ratio: 16 / 10;
  overflow: hidden;
}

.tech-card__img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.6s ease;
}

.tech-card:hover .tech-card__img {
  transform: scale(1.04);
}

.tech-card__body {
  padding: 32px;
  display: flex;
  flex-direction: column;
  gap: 14px;
  flex: 1;
}

.tech-card__title {
  font-size: 1.5rem;
  font-weight: 700;
  color: #ffffff;
}

.tech-card__descr {
  font-size: 1.02rem;
  color: var(--text-muted);
  line-height: 1.6;
}

.tech-card__btn {
  margin-top: auto;
  align-self: flex-start;
}

/* Quote Banner / Big Technology Statement */
.quote-banner {
  background: linear-gradient(135deg, rgba(37, 99, 235, 0.15) 0%, rgba(2, 132, 199, 0.08) 100%);
  border: 1px solid rgba(56, 189, 248, 0.25);
  border-radius: var(--radius-lg);
  padding: 50px 40px;
  margin-top: 60px;
  text-align: center;
  position: relative;
  box-shadow: var(--shadow-glow);
}

.quote-banner__text {
  font-size: clamp(1.15rem, 2.2vw, 1.45rem);
  font-weight: 500;
  line-height: 1.65;
  color: #f8fafc;
  max-width: 980px;
  margin: 0 auto;
}

/* ==========================================================================
   6. Advantages Section (Преимущества)
   ========================================================================== */
.advantages-section {
  background: var(--bg-surface-alt);
  border-top: 1px solid var(--border-subtle);
  border-bottom: 1px solid var(--border-subtle);
}

.advantages-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 28px;
}

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

.advantage-card {
  display: flex;
  align-items: flex-start;
  gap: 20px;
  padding: 32px;
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  transition: var(--transition-base);
}

.advantage-card:hover {
  transform: translateY(-4px);
  border-color: rgba(56, 189, 248, 0.35);
  background: var(--bg-surface-elevated);
}

.advantage-icon-wrapper {
  width: 48px;
  height: 48px;
  border-radius: 12px;
  background: rgba(37, 99, 235, 0.15);
  border: 1px solid rgba(56, 189, 248, 0.3);
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}

.advantage-icon {
  width: 24px;
  height: 24px;
  filter: brightness(0) invert(1);
}

.advantage-content h3 {
  font-size: 1.25rem;
  font-weight: 700;
  color: #ffffff;
  margin-bottom: 8px;
}

.advantage-content p {
  font-size: 0.98rem;
  color: var(--text-muted);
  line-height: 1.6;
}

/* ==========================================================================
   7. FAQ Section (Часто задаваемые вопросы)
   ========================================================================== */
.faq-section {
  background: var(--bg-primary);
}

.faq-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 24px;
  max-width: 1100px;
  margin: 0 auto;
}

@media (max-width: 860px) {
  .faq-grid {
    grid-template-columns: 1fr;
  }
}

.faq-card {
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 32px;
  display: flex;
  align-items: flex-start;
  gap: 20px;
  transition: var(--transition-base);
}

.faq-card:hover {
  border-color: rgba(37, 99, 235, 0.4);
  background: var(--bg-surface-elevated);
  transform: translateY(-3px);
}

.faq-icon-box {
  width: 44px;
  height: 44px;
  border-radius: 10px;
  background: rgba(2, 132, 199, 0.15);
  border: 1px solid rgba(2, 132, 199, 0.3);
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}

.faq-icon {
  width: 22px;
  height: 22px;
  filter: brightness(0) invert(1);
}

.faq-text h3 {
  font-size: 1.2rem;
  font-weight: 700;
  color: #ffffff;
  margin-bottom: 8px;
}

.faq-text p {
  font-size: 0.96rem;
  color: var(--text-muted);
  line-height: 1.6;
}

/* ==========================================================================
   8. Contacts Section (Контакты)
   ========================================================================== */
.contacts-section {
  background: var(--bg-surface);
  border-top: 1px solid var(--border-subtle);
}

.contacts-cards-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 28px;
  max-width: 1080px;
  margin: 0 auto;
}

@media (max-width: 860px) {
  .contacts-cards-grid {
    grid-template-columns: 1fr;
    gap: 20px;
  }
}

.contact-card-box {
  background: var(--bg-surface-elevated);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  padding: 36px 28px;
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
  transition: var(--transition-base);
  box-shadow: var(--shadow-sm);
}

.contact-card-box:hover {
  transform: translateY(-5px);
  border-color: rgba(56, 189, 248, 0.4);
  box-shadow: 0 16px 36px rgba(0, 0, 0, 0.4);
}

.contact-card-icon {
  width: 56px;
  height: 56px;
  border-radius: 16px;
  background: rgba(37, 99, 235, 0.15);
  border: 1px solid rgba(56, 189, 248, 0.3);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--accent-light);
  margin-bottom: 20px;
}

.contact-card-label {
  font-size: 0.82rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--text-dim);
  margin-bottom: 8px;
}

.contact-card-value {
  font-size: 1.18rem;
  font-weight: 700;
  color: #ffffff;
  line-height: 1.4;
}

.contact-card-link {
  font-size: 1.12rem;
  font-weight: 600;
  color: var(--accent-light);
  word-break: break-all;
  line-height: 1.4;
  transition: var(--transition-fast);
}

.contact-card-link:hover {
  color: #ffffff;
  text-decoration: underline;
}

/* Feedback CTA Card (Link to Yandex Form) */
.feedback-cta-card {
  position: relative;
  max-width: 1080px;
  margin: 48px auto 0;
  background: linear-gradient(135deg, rgba(31, 41, 61, 0.9) 0%, rgba(22, 32, 50, 0.95) 100%);
  border: 1px solid rgba(56, 189, 248, 0.22);
  border-radius: var(--radius-lg);
  padding: 42px 48px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 36px;
  box-shadow: 0 10px 32px rgba(0, 0, 0, 0.35);
  overflow: hidden;
  transition: var(--transition-base);
}

.feedback-cta-card:hover {
  border-color: rgba(56, 189, 248, 0.45);
  box-shadow: 0 16px 40px rgba(0, 0, 0, 0.45), 0 0 30px rgba(37, 99, 235, 0.15);
}

.feedback-cta-glow {
  position: absolute;
  top: -50px;
  right: -50px;
  width: 250px;
  height: 250px;
  background: radial-gradient(circle, rgba(56, 189, 248, 0.15) 0%, transparent 70%);
  pointer-events: none;
}

.feedback-cta-content {
  flex: 1;
  max-width: 620px;
}

.feedback-cta-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 4px 14px;
  border-radius: var(--radius-full);
  background: rgba(56, 189, 248, 0.12);
  border: 1px solid rgba(56, 189, 248, 0.25);
  color: var(--accent-light);
  font-size: 0.82rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: 12px;
}

.feedback-cta-title {
  font-size: 1.5rem;
  font-weight: 700;
  color: #ffffff;
  line-height: 1.3;
  margin-bottom: 8px;
  letter-spacing: -0.01em;
}

.feedback-cta-descr {
  font-size: 0.95rem;
  color: var(--text-muted);
  line-height: 1.6;
}

.feedback-cta-actions {
  display: flex;
  flex-direction: column;
  align-items: flex-end;
  gap: 10px;
  flex-shrink: 0;
}

.btn-feedback {
  padding: 15px 30px;
  font-size: 1rem;
  box-shadow: 0 6px 24px rgba(37, 99, 235, 0.35);
}

.feedback-cta-note {
  font-size: 0.8rem;
  color: var(--text-dim);
  text-align: right;
}

@media (max-width: 900px) {
  .feedback-cta-card {
    flex-direction: column;
    align-items: flex-start;
    padding: 30px 22px;
    gap: 22px;
    margin-top: 32px;
  }

  .feedback-cta-actions {
    width: 100%;
    align-items: stretch;
  }

  .btn-feedback {
    width: 100%;
  }

  .feedback-cta-note {
    text-align: center;
  }
}

/* ==========================================================================
   9. Footer
   ========================================================================== */
.site-footer {
  background: #060913;
  border-top: 1px solid var(--border-subtle);
  padding: 60px 0 30px;
}

.footer-top {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 30px;
  margin-bottom: 40px;
  padding-bottom: 40px;
  border-bottom: 1px solid var(--border-subtle);
}

.footer-brand {
  max-width: 420px;
}

.footer-brand .nav-brand {
  margin-bottom: 12px;
}

.footer-brand p {
  color: var(--text-dim);
  font-size: 0.9rem;
  line-height: 1.6;
}

.footer-links {
  display: flex;
  flex-wrap: wrap;
  gap: 24px;
}

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

.footer-link:hover {
  color: #ffffff;
}

.footer-bottom {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 20px;
  font-size: 0.85rem;
  color: var(--text-dim);
}

.back-to-top-btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  color: var(--accent-light);
  font-weight: 500;
  transition: var(--transition-fast);
}

.back-to-top-btn:hover {
  color: #ffffff;
  transform: translateY(-2px);
}

/* ==========================================================================
   10. Modals / Lightbox
   ========================================================================== */
.lightbox-modal {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.9);
  backdrop-filter: blur(12px);
  z-index: 1000;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 24px;
  opacity: 0;
  visibility: hidden;
  transition: opacity 0.3s ease, visibility 0.3s ease;
}

.lightbox-modal.active {
  opacity: 1;
  visibility: visible;
}

.lightbox-content {
  position: relative;
  max-width: 90vw;
  max-height: 90vh;
  display: flex;
  flex-direction: column;
  align-items: center;
}

.lightbox-img {
  max-width: 100%;
  max-height: 80vh;
  object-fit: contain;
  border-radius: var(--radius-md);
  box-shadow: 0 20px 60px rgba(0, 0, 0, 0.8);
}

.lightbox-caption {
  margin-top: 14px;
  color: #ffffff;
  font-size: 1.1rem;
  font-weight: 600;
  text-align: center;
}

.lightbox-close {
  position: absolute;
  top: -46px;
  right: 0;
  background: none;
  border: none;
  color: #ffffff;
  font-size: 2.2rem;
  cursor: pointer;
  line-height: 1;
  opacity: 0.8;
  transition: opacity 0.2s;
}

.lightbox-close:hover {
  opacity: 1;
}