/* ==============================
   CSS Variables & Reset
   ============================== */

:root {
  /* Colors */
  --bg-primary: #0a0a0f;
  --bg-card: #111827;
  --bg-card-hover: #1a1f2e;
  --border: #1f2937;
  --border-hover: #374151;

  --text-primary: #e2e8f0;
  --text-secondary: #94a3b8;
  --text-muted: #64748b;
  --text-heading: #ffffff;

  --accent-start: #6366f1;
  --accent-end: #8b5cf6;
  --accent-glow: rgba(99, 102, 241, 0.15);

  /* Spacing */
  --section-py: 120px;
  --container-px: 24px;
  --container-max: 1120px;

  /* Radius */
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 16px;
  --radius-xl: 24px;

  /* Transitions */
  --transition: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

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

html {
  scroll-behavior: smooth;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  background-color: var(--bg-primary);
  color: var(--text-primary);
  font-size: 16px;
  line-height: 1.6;
  overflow-x: hidden;
}

a {
  color: inherit;
  text-decoration: none;
}

ul {
  list-style: none;
}

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

strong {
  color: var(--text-heading);
  font-weight: 600;
}

/* ==============================
   Utilities
   ============================== */

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

.accent {
  background: linear-gradient(135deg, var(--accent-start), var(--accent-end));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.section-title {
  font-size: clamp(2rem, 5vw, 3rem);
  font-weight: 800;
  color: var(--text-heading);
  text-align: center;
  margin-bottom: 12px;
  letter-spacing: -0.02em;
}

.section-subtitle {
  font-size: 1.125rem;
  color: var(--text-secondary);
  text-align: center;
  max-width: 600px;
  margin: 0 auto 60px;
}

/* ==============================
   Buttons
   ============================== */

.btn {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 14px 32px;
  border-radius: var(--radius-md);
  font-size: 1rem;
  font-weight: 600;
  cursor: pointer;
  transition: var(--transition);
  border: none;
  white-space: nowrap;
}

.btn--primary {
  background: linear-gradient(135deg, var(--accent-start), var(--accent-end));
  color: #fff;
  box-shadow: 0 4px 24px rgba(99, 102, 241, 0.3);
}

.btn--primary:hover {
  box-shadow: 0 8px 32px rgba(99, 102, 241, 0.5);
  transform: translateY(-2px);
}

.btn--ghost {
  background: transparent;
  color: var(--text-primary);
  border: 1px solid var(--border);
}

.btn--ghost:hover {
  border-color: var(--accent-start);
  color: var(--text-heading);
  background: var(--accent-glow);
}

.btn--lg {
  padding: 18px 40px;
  font-size: 1.125rem;
  border-radius: var(--radius-lg);
}

/* ==============================
   Navigation
   ============================== */

.nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  padding: 16px 0;
  transition: var(--transition);
  background: transparent;
}

.nav--scrolled {
  background: rgba(10, 10, 15, 0.85);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--border);
  padding: 12px 0;
}

.nav__container {
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 var(--container-px);
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.nav__logo {
  font-size: 1.5rem;
  font-weight: 800;
  color: var(--text-heading);
  letter-spacing: -0.02em;
}

.nav__links {
  display: flex;
  align-items: center;
  gap: 32px;
}

.nav__links a {
  font-size: 0.9375rem;
  font-weight: 500;
  color: var(--text-secondary);
  transition: var(--transition);
}

.nav__links a:hover {
  color: var(--text-heading);
}

.nav__cta {
  padding: 10px 24px;
  border-radius: var(--radius-md);
  background: linear-gradient(135deg, var(--accent-start), var(--accent-end));
  color: #fff !important;
}

.nav__cta:hover {
  box-shadow: 0 4px 20px rgba(99, 102, 241, 0.4);
}

.nav__burger {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 4px;
}

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

/* ==============================
   Hero
   ============================== */

.hero {
  position: relative;
  min-height: 100vh;
  display: flex;
  align-items: center;
  padding: 120px 0 80px;
  overflow: hidden;
}

.hero__grid-bg {
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(99, 102, 241, 0.06) 1px, transparent 1px),
    linear-gradient(90deg, rgba(99, 102, 241, 0.06) 1px, transparent 1px);
  background-size: 60px 60px;
  mask-image: radial-gradient(ellipse 70% 60% at 50% 40%, black 30%, transparent 70%);
  -webkit-mask-image: radial-gradient(ellipse 70% 60% at 50% 40%, black 30%, transparent 70%);
}

.hero__glow {
  position: absolute;
  top: -200px;
  left: 50%;
  transform: translateX(-50%);
  width: 800px;
  height: 800px;
  background: radial-gradient(circle, rgba(99, 102, 241, 0.12) 0%, rgba(139, 92, 246, 0.06) 40%, transparent 70%);
  pointer-events: none;
}

.hero__content {
  position: relative;
  z-index: 1;
  max-width: 720px;
}

.hero__tag {
  display: inline-block;
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--accent-start);
  letter-spacing: 0.05em;
  text-transform: uppercase;
  margin-bottom: 24px;
}

.hero__title {
  font-size: clamp(3rem, 8vw, 5.5rem);
  font-weight: 800;
  color: var(--text-heading);
  line-height: 1.05;
  letter-spacing: -0.03em;
  margin-bottom: 24px;
}

.hero__subtitle {
  font-size: clamp(1.25rem, 3vw, 1.75rem);
  font-weight: 600;
  color: var(--text-primary);
  line-height: 1.3;
  margin-bottom: 20px;
}

.hero__description {
  font-size: 1.125rem;
  color: var(--text-secondary);
  line-height: 1.7;
  margin-bottom: 40px;
  max-width: 560px;
}

.hero__actions {
  display: flex;
  gap: 16px;
  flex-wrap: wrap;
}

/* ==============================
   Services
   ============================== */

.services {
  padding: var(--section-py) 0;
}

.services__grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
  margin-bottom: 48px;
}

/* Card */
.card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-xl);
  padding: 36px;
  transition: var(--transition);
}

.card:hover {
  border-color: var(--border-hover);
  background: var(--bg-card-hover);
  transform: translateY(-4px);
  box-shadow: 0 12px 40px rgba(0, 0, 0, 0.3);
}

.card__icon {
  width: 56px;
  height: 56px;
  border-radius: var(--radius-md);
  background: linear-gradient(135deg, var(--accent-start), var(--accent-end));
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 20px;
  color: #fff;
}

.card__title {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--text-heading);
  margin-bottom: 12px;
  line-height: 1.3;
}

.card__text {
  font-size: 0.9375rem;
  color: var(--text-secondary);
  line-height: 1.65;
}

/* Tech badges */
.tech-badges {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 10px;
}

.badge {
  display: inline-block;
  padding: 8px 16px;
  font-size: 0.8125rem;
  font-weight: 500;
  color: var(--text-secondary);
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 100px;
  transition: var(--transition);
}

.badge:hover {
  border-color: var(--accent-start);
  color: var(--text-heading);
  background: var(--accent-glow);
}

/* ==============================
   Cases
   ============================== */

.cases {
  padding: var(--section-py) 0;
  background:
    linear-gradient(180deg, transparent 0%, rgba(99, 102, 241, 0.02) 50%, transparent 100%);
}

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

.case {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-xl);
  padding: 36px;
  transition: var(--transition);
}

.case:hover {
  border-color: var(--border-hover);
  box-shadow: 0 8px 32px rgba(0, 0, 0, 0.25);
}

.case__header {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 16px;
}

.case__number {
  font-size: 0.8125rem;
  font-weight: 700;
  color: var(--accent-start);
  background: var(--accent-glow);
  padding: 4px 10px;
  border-radius: var(--radius-sm);
}

.case__category {
  font-size: 0.8125rem;
  font-weight: 500;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.case__title {
  font-size: 1.375rem;
  font-weight: 700;
  color: var(--text-heading);
  line-height: 1.3;
  margin-bottom: 8px;
}

.case__meta {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 0.875rem;
  color: var(--text-muted);
  margin-bottom: 24px;
}

.case__dot {
  width: 4px;
  height: 4px;
  border-radius: 50%;
  background: var(--text-muted);
}

.case__body {
  display: flex;
  flex-direction: column;
  gap: 20px;
  margin-bottom: 24px;
}

.case__block h4 {
  font-size: 0.8125rem;
  font-weight: 600;
  color: var(--accent-start);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: 8px;
}

.case__block p {
  font-size: 0.9375rem;
  color: var(--text-secondary);
  line-height: 1.65;
}

.case__results {
  display: flex;
  flex-direction: column;
  gap: 6px;
  padding-left: 0;
}

.case__results li {
  font-size: 0.9375rem;
  color: var(--text-secondary);
  line-height: 1.65;
  padding-left: 20px;
  position: relative;
}

.case__results li::before {
  content: '';
  position: absolute;
  left: 0;
  top: 10px;
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--accent-start), var(--accent-end));
}

.case__stack {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  padding-top: 20px;
  border-top: 1px solid var(--border);
}

.case__stack span {
  font-size: 0.75rem;
  font-weight: 500;
  color: var(--text-muted);
  background: rgba(255, 255, 255, 0.04);
  padding: 4px 12px;
  border-radius: 100px;
  border: 1px solid var(--border);
}

/* ==============================
   Process
   ============================== */

.process {
  padding: var(--section-py) 0;
}

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

.process__step {
  text-align: center;
  padding: 32px 24px;
  border-radius: var(--radius-xl);
  border: 1px solid transparent;
  transition: var(--transition);
}

.process__step:hover {
  border-color: var(--border);
  background: var(--bg-card);
}

.process__number {
  font-size: 2.5rem;
  font-weight: 800;
  background: linear-gradient(135deg, var(--accent-start), var(--accent-end));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  margin-bottom: 16px;
  line-height: 1;
}

.process__step h3 {
  font-size: 1.125rem;
  font-weight: 700;
  color: var(--text-heading);
  margin-bottom: 10px;
}

.process__step p {
  font-size: 0.9375rem;
  color: var(--text-secondary);
  line-height: 1.6;
}

/* ==============================
   Contacts
   ============================== */

.contacts {
  padding: var(--section-py) 0;
  background:
    linear-gradient(180deg, transparent 0%, rgba(99, 102, 241, 0.03) 50%, transparent 100%);
}

.contacts__buttons {
  display: flex;
  justify-content: center;
  gap: 16px;
  flex-wrap: wrap;
  margin-bottom: 40px;
}

.contacts__info {
  text-align: center;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.contacts__info p {
  font-size: 0.9375rem;
  color: var(--text-muted);
}

.contacts__info a {
  color: var(--text-secondary);
  transition: var(--transition);
}

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

/* ==============================
   Footer
   ============================== */

.footer {
  padding: 40px 0;
  border-top: 1px solid var(--border);
  text-align: center;
}

.footer p {
  font-size: 0.875rem;
  color: var(--text-muted);
}

/* ==============================
   Responsive
   ============================== */

@media (max-width: 1024px) {
  :root {
    --section-py: 80px;
  }

  .services__grid {
    grid-template-columns: 1fr;
    max-width: 480px;
    margin-left: auto;
    margin-right: auto;
  }

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

  .process__grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 768px) {
  :root {
    --section-py: 64px;
    --container-px: 16px;
  }

  .nav__links {
    position: fixed;
    top: 0;
    right: -100%;
    width: 280px;
    height: 100vh;
    background: rgba(10, 10, 15, 0.97);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    flex-direction: column;
    justify-content: center;
    gap: 24px;
    padding: 40px;
    transition: right 0.4s cubic-bezier(0.4, 0, 0.2, 1);
    border-left: 1px solid var(--border);
  }

  .nav__links.active {
    right: 0;
  }

  .nav__links a {
    font-size: 1.125rem;
  }

  .nav__burger {
    display: flex;
    z-index: 1001;
  }

  .nav__burger.active span:nth-child(1) {
    transform: translateY(7px) rotate(45deg);
  }

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

  .nav__burger.active span:nth-child(3) {
    transform: translateY(-7px) rotate(-45deg);
  }

  .hero {
    padding-top: 100px;
    min-height: auto;
  }

  .hero__actions {
    flex-direction: column;
  }

  .hero__actions .btn {
    text-align: center;
    justify-content: center;
  }

  .section-subtitle {
    margin-bottom: 40px;
  }

  .case {
    padding: 24px;
  }

  .process__grid {
    grid-template-columns: 1fr;
    max-width: 400px;
    margin-left: auto;
    margin-right: auto;
  }

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

  .btn--lg {
    padding: 16px 32px;
    font-size: 1rem;
  }
}