/* ================================================================
   НАИС — Система обогрева тензодатчиков
   ================================================================ */

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

:root {
  --bg:        #F4F3F2;
  --bg-alt:    #EBEBEA;
  --bg-dark:   #252924;
  --olive:     #3E4919;
  --olive-mid: #6B7A4A;
  --olive-lt:  #A0AB7B;
  --stone:     #595C58;
  --white:     #FFFFFF;
  --text:      #252924;
  --text-dim:  #595C58;
  --error:     #C0392B;
  --border:    rgba(37,41,36,0.10);
}

html { scroll-behavior: smooth; }

body {
  background: var(--bg);
  color: var(--text);
  font-family: 'Ubuntu', sans-serif;
  font-size: 16px;
  line-height: 1.65;
  overflow-x: hidden;
}

/* ── NAV ───────────────────────────────────────── */
nav {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 100;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 48px;
  height: 60px;
  background: rgba(244,243,242,0.96);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--border);
}

.nav-logo img { height: 32px; width: auto; display: block; }

.nav-right { display: flex; align-items: center; gap: 12px; }

.nav-cta-top {
  display: inline-block;
  background: var(--olive);
  color: var(--white);
  font-family: 'Ubuntu', sans-serif;
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  padding: 8px 18px;
  text-decoration: none;
  border-radius: 2px;
  white-space: nowrap;
  transition: background 0.2s;
}
.nav-cta-top:hover { background: var(--bg-dark); }

/* Бургер */
.burger {
  display: none;
  flex-direction: column;
  gap: 6px;
  cursor: pointer;
  padding: 6px;
  background: none;
  border: none;
  z-index: 200;
}
.burger span {
  display: block;
  width: 24px;
  height: 2px;
  background: var(--bg-dark);
  border-radius: 1px;
  transition: all 0.25s;
}
.burger.open span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.burger.open span:nth-child(2) { opacity: 0; }
.burger.open span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

/* Drawer */
.nav-drawer {
  position: fixed;
  top: 60px; right: 0;
  width: 260px;
  height: calc(100vh - 60px);
  background: var(--white);
  border-left: 1px solid var(--border);
  display: flex !important;
  flex-direction: column;
  justify-content: flex-start;
  align-items: stretch;
  padding: 24px 0;
  transform: translateX(100%);
  transition: transform 0.28s cubic-bezier(0.4,0,0.2,1);
  z-index: 150;
  box-shadow: -6px 0 32px rgba(37,41,36,0.10);
  overflow-y: auto;
}
.nav-drawer.open { transform: translateX(0); }

.nav-drawer a {
  display: block;
  color: var(--stone);
  text-decoration: none;
  font-size: 13px;
  font-weight: 500;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  padding: 14px 32px;
  border-bottom: 1px solid var(--border);
  transition: color 0.2s, background 0.2s;
}
.nav-drawer a:hover { color: var(--olive); background: var(--bg); }

.nav-drawer .nav-cta {
  margin: 24px 32px 0;
  display: block;
  background: var(--olive);
  color: var(--white) !important;
  padding: 14px 20px;
  border-radius: 2px;
  text-align: center;
  border-bottom: none;
}
.nav-drawer .nav-cta:hover { background: var(--bg-dark) !important; }

/* Overlay */
.nav-overlay {
  position: fixed;
  inset: 0;
  background: rgba(37,41,36,0.3);
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.3s;
  z-index: 140;
}
.nav-overlay.open { opacity: 1; pointer-events: all; }

/* Skip-link: скрыт, появляется по фокусу */
.skip-link {
  position: absolute;
  left: 16px;
  top: -48px;
  z-index: 300;
  background: var(--olive);
  color: var(--white);
  font-size: 13px;
  font-weight: 500;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  padding: 12px 20px;
  border-radius: 2px;
  text-decoration: none;
  transition: top 0.2s;
}
.skip-link:focus { top: 16px; }
#home { scroll-margin-top: 76px; }

/* ── BUTTONS ───────────────────────────────────── */
.btn-primary {
  display: inline-block;
  background: var(--olive);
  color: var(--white);
  font-family: 'Ubuntu', sans-serif;
  font-size: 15px;
  font-weight: 700;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  padding: 16px 36px;
  text-decoration: none;
  border-radius: 2px;
  border: none;
  cursor: pointer;
  transition: background 0.2s, transform 0.15s;
}
.btn-primary:hover { background: var(--bg-dark); transform: translateY(-1px); }

.btn-ghost {
  display: inline-block;
  color: var(--olive);
  font-size: 14px;
  font-weight: 500;
  text-decoration: none;
  border-bottom: 1px solid var(--olive-lt);
  padding-bottom: 2px;
  transition: color 0.2s, border-color 0.2s;
}
.btn-ghost:hover { color: var(--bg-dark); border-color: var(--bg-dark); }

/* ── HERO ──────────────────────────────────────── */
.hero {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  justify-content: center;
  padding: 120px 48px 80px;
  position: relative;
  overflow: hidden;
  background: var(--bg-dark);
}

.hero-stripes {
  position: absolute;
  top: 0; right: 0;
  width: 380px;
  height: 100%;
  z-index: 1;
  background-image: repeating-linear-gradient(
    -45deg,
    rgba(107,122,74,0.22) 0px,
    rgba(107,122,74,0.22) 14px,
    transparent 14px,
    transparent 32px
  );
  mask-image: linear-gradient(to left, rgba(0,0,0,0.6) 0%, transparent 100%);
  -webkit-mask-image: linear-gradient(to left, rgba(0,0,0,0.6) 0%, transparent 100%);
}

.hero-content { position: relative; z-index: 2; max-width: 800px; }

.hero-eyebrow {
  font-size: 12px;
  font-weight: 500;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--olive-lt);
  margin-bottom: 24px;
  display: flex;
  align-items: center;
  gap: 12px;
}
.hero-eyebrow::before {
  content: '';
  display: inline-block;
  width: 28px;
  height: 1px;
  background: var(--olive-lt);
}

.hero h1 {
  font-size: clamp(38px, 5.5vw, 72px);
  font-weight: 700;
  line-height: 1.06;
  color: var(--white);
  text-transform: uppercase;
  letter-spacing: 0.01em;
  margin-bottom: 28px;
}
.hero h1 .accent { color: var(--olive-lt); }

.hero-sub {
  font-size: 17px;
  font-weight: 300;
  color: rgba(255,255,255,0.65);
  max-width: 520px;
  line-height: 1.75;
  margin-bottom: 44px;
}

.hero-actions { display: flex; gap: 20px; align-items: center; flex-wrap: wrap; }

.hero-stats {
  display: flex;
  gap: 48px;
  margin-top: 72px;
  padding-top: 40px;
  border-top: 1px solid rgba(255,255,255,0.1);
  flex-wrap: wrap;
}

.stat-num {
  font-size: 40px;
  font-weight: 700;
  color: var(--white);
  line-height: 1;
  margin-bottom: 6px;
}
.stat-num span { color: var(--olive-lt); }
.stat-label {
  font-size: 12px;
  font-weight: 400;
  color: rgba(255,255,255,0.5);
  letter-spacing: 0.06em;
  text-transform: uppercase;
  max-width: 160px;
}

/* ── TEMP BADGE ─────────────────────────────────── */
.temp-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: rgba(62,73,25,0.35);
  border: 1px solid rgba(160,171,123,0.3);
  padding: 6px 14px;
  border-radius: 2px;
  font-size: 12px;
  color: var(--olive-lt);
  font-weight: 500;
  margin-bottom: 28px;
  letter-spacing: 0.04em;
}
.temp-dot {
  width: 6px; height: 6px;
  background: var(--olive-lt);
  border-radius: 50%;
  animation: pulse 2.4s ease-in-out infinite;
}
@keyframes pulse { 0%,100%{opacity:1} 50%{opacity:0.3} }

/* ── SECTIONS ───────────────────────────────────── */
section { padding: 96px 48px; }

.section-eyebrow {
  font-size: 12px;
  font-weight: 500;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--olive);
  margin-bottom: 14px;
  display: flex;
  align-items: center;
  gap: 10px;
}
.section-eyebrow::before {
  content: '';
  display: inline-block;
  width: 24px;
  height: 2px;
  background: var(--olive);
}

h2 {
  font-size: clamp(26px, 3.5vw, 44px);
  font-weight: 700;
  color: var(--bg-dark);
  text-transform: uppercase;
  letter-spacing: 0.02em;
  line-height: 1.1;
  margin-bottom: 20px;
}

.section-lead {
  font-size: 16px;
  font-weight: 300;
  color: var(--text-dim);
  max-width: 580px;
  line-height: 1.8;
  margin-bottom: 60px;
}

/* ── PROBLEM SECTION ────────────────────────────── */
.problem-section { background: var(--white); }

.problem-photos {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
  margin-bottom: 40px;
}
.problem-photos img {
  width: 100%;
  height: auto;
  display: block;
  border-radius: 3px;
}
@media (max-width: 768px) {
  .problem-photos {
    grid-template-columns: 1fr;
  }
}

.problem-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 0;
  margin-top: 48px;
}

.problem-card {
  background: var(--white);
  padding: 36px 32px;
  position: relative;
  box-shadow: 0 0 0 1px var(--border);
}
.problem-card::after {
  content: '';
  position: absolute;
  top: 0; left: 0;
  width: 100%;
  height: 4px;
  background: var(--bg-alt);
  transition: background 0.3s;
}
.problem-card:hover::after { background: var(--olive); }

.problem-card h3 {
  font-size: 16px;
  font-weight: 700;
  color: var(--bg-dark);
  text-transform: uppercase;
  letter-spacing: 0.04em;
  margin-bottom: 12px;
  margin-top: 20px;
}
.problem-card p { font-size: 14px; color: var(--text-dim); line-height: 1.75; }

.problem-icon { width: 40px; height: 40px; flex-shrink: 0; display: block; }

/* ── RESULTS SECTION ────────────────────────────── */
.results-section { background: var(--bg-alt); }

.results-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 0;
  margin-top: 48px;
}

.results-card {
  background: var(--bg-alt);
  padding: 36px 32px;
  transition: background 0.2s;
  box-shadow: 0 0 0 1px var(--border);
}
.results-card:hover { background: var(--bg); }

.results-icon {
  width: 40px;
  height: 40px;
  flex-shrink: 0;
  display: block;
  margin-bottom: 20px;
}

.results-card h3 {
  font-size: 16px;
  font-weight: 700;
  color: var(--bg-dark);
  text-transform: uppercase;
  letter-spacing: 0.06em;
  margin-bottom: 10px;
  line-height: 1.3;
}
.results-card p { font-size: 14px; color: var(--text-dim); line-height: 1.75; }

/* ── HOW IT WORKS ───────────────────────────────── */
.how-section { background: var(--bg); }

.tech-layout {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 72px;
  align-items: center;
}

.tech-diagram {
  background: var(--bg-dark);
  border-radius: 3px;
  padding: 44px;
  position: relative;
  overflow: hidden;
}
.tech-diagram img {
  width: 100%;
  height: auto;
  display: block;
}
.tech-diagram::before {
  content: '';
  position: absolute;
  top: 0; right: 0;
  width: 120px;
  height: 100%;
  background-image: repeating-linear-gradient(
    -45deg,
    rgba(107,122,74,0.18) 0px,
    rgba(107,122,74,0.18) 10px,
    transparent 10px,
    transparent 22px
  );
  mask-image: linear-gradient(to left, rgba(0,0,0,0.5) 0%, transparent 100%);
  -webkit-mask-image: linear-gradient(to left, rgba(0,0,0,0.5) 0%, transparent 100%);
  pointer-events: none;
}

.spec-item {
  display: flex;
  gap: 20px;
  padding: 22px 0;
  border-bottom: 1px solid var(--border);
}
.spec-item:last-child { border-bottom: none; }

.spec-num {
  font-size: 28px;
  font-weight: 700;
  color: var(--olive-lt);
  opacity: 0.6;
  line-height: 1;
  flex-shrink: 0;
  width: 36px;
}

.spec-body h4 {
  font-size: 16px;
  font-weight: 700;
  color: var(--bg-dark);
  text-transform: uppercase;
  letter-spacing: 0.04em;
  margin-bottom: 5px;
}
.spec-body p { font-size: 14px; color: var(--text-dim); line-height: 1.7; }

/* ── BENEFITS ───────────────────────────────────── */
.benefits-section { background: var(--white); }

.benefits-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1px;
  background: var(--border);
  border: 1px solid var(--border);
}

.benefit-card {
  background: var(--white);
  padding: 36px 32px;
  transition: background 0.2s;
}
.benefit-card:hover { background: var(--bg); }

.benefit-tag {
  display: inline-block;
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--olive);
  border: 1px solid rgba(62,73,25,0.25);
  padding: 4px 8px;
  margin-bottom: 20px;
  border-radius: 1px;
}

.benefit-card h3 {
  font-size: 16px;
  font-weight: 700;
  color: var(--bg-dark);
  text-transform: uppercase;
  letter-spacing: 0.03em;
  margin-bottom: 10px;
  line-height: 1.25;
}
.benefit-card p { font-size: 14px; color: var(--text-dim); line-height: 1.75; }

/* ── PRICE ──────────────────────────────────────── */
.price-section { background: var(--bg); }

.price-layout {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 72px;
  align-items: start;
}

.price-card {
  background: var(--bg-dark);
  padding: 52px;
  position: relative;
  overflow: hidden;
}
.price-card::before {
  content: '';
  position: absolute;
  top: 0; left: 0; right: 0;
  height: 4px;
  background: var(--olive);
}
.price-card::after {
  content: '';
  position: absolute;
  top: 0; right: 0;
  width: 100px;
  height: 100%;
  background-image: repeating-linear-gradient(
    -45deg,
    rgba(107,122,74,0.15) 0px,
    rgba(107,122,74,0.15) 8px,
    transparent 8px,
    transparent 18px
  );
  mask-image: linear-gradient(to left, rgba(0,0,0,0.5) 0%, transparent 100%);
  -webkit-mask-image: linear-gradient(to left, rgba(0,0,0,0.5) 0%, transparent 100%);
  pointer-events: none;
}

.price-label {
  font-size: 12px;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: rgba(255,255,255,0.5);
  margin-bottom: 12px;
}
.price-amount {
  font-size: 60px;
  font-weight: 700;
  color: var(--white);
  line-height: 1;
  margin-bottom: 4px;
}
.price-amount span { font-size: 28px; color: rgba(255,255,255,0.4); font-weight: 300; }

.price-note {
  font-size: 13px;
  color: rgba(255,255,255,0.5);
  margin-bottom: 36px;
  padding-bottom: 36px;
  border-bottom: 1px solid rgba(255,255,255,0.1);
  line-height: 1.65;
}

.price-includes { list-style: none; }
.price-includes li {
  display: flex;
  align-items: flex-start;
  gap: 12px;
  font-size: 14px;
  color: rgba(255,255,255,0.7);
  margin-bottom: 12px;
  line-height: 1.55;
}
.price-includes li::before {
  content: '';
  display: inline-block;
  width: 6px; height: 6px;
  background: var(--olive-lt);
  border-radius: 50%;
  margin-top: 7px;
  flex-shrink: 0;
}

.price-btn {
  margin-top: 36px;
  width: 100%;
  text-align: center;
  padding: 16px;
  font-size: 15px;
  background: var(--olive);
  position: relative;
  z-index: 1;
}
.price-btn:hover { background: var(--olive-mid); }

.price-specs { padding-top: 4px; }
.price-specs h3 {
  font-size: 20px;
  font-weight: 700;
  color: var(--bg-dark);
  text-transform: uppercase;
  letter-spacing: 0.04em;
  margin-bottom: 28px;
}

.spec-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 16px 0;
  border-bottom: 1px solid var(--border);
}
.spec-row:last-child { border-bottom: none; }
.spec-row-label { font-size: 14px; color: var(--text-dim); }
.spec-row-val {
  font-size: 14px;
  font-weight: 700;
  color: var(--bg-dark);
  text-align: right;
}

/* ── CONTACT ────────────────────────────────────── */
.contact-section {
  background: var(--olive);
  text-align: center;
  padding: 80px 48px;
  position: relative;
  overflow: hidden;
}
.contact-section::after {
  content: '';
  position: absolute;
  top: 0; right: 0;
  width: 50%;
  height: 100%;
  background-image: repeating-linear-gradient(
    -45deg,
    rgba(255,255,255,0.06) 0px,
    rgba(255,255,255,0.06) 14px,
    transparent 14px,
    transparent 30px
  );
  pointer-events: none;
}

.contact-section h2 { color: var(--white); margin-bottom: 14px; }
.contact-section .section-eyebrow {
  justify-content: center;
  color: rgba(255,255,255,0.6);
}
.contact-section p { color: rgba(255,255,255,0.65); font-size: 16px; margin-bottom: 40px; }

.contact-actions {
  display: flex;
  gap: 16px;
  justify-content: center;
  flex-wrap: wrap;
  margin-bottom: 48px;
  position: relative;
  z-index: 1;
}

.btn-white {
  display: inline-block;
  background: var(--white);
  color: var(--olive);
  font-family: 'Ubuntu', sans-serif;
  font-size: 15px;
  font-weight: 700;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  padding: 16px 32px;
  text-decoration: none;
  border-radius: 2px;
  transition: background 0.2s, color 0.2s;
}
.btn-white:hover { background: var(--bg-dark); color: var(--white); }

.contact-meta {
  display: flex;
  gap: 48px;
  justify-content: center;
  flex-wrap: wrap;
  position: relative;
  z-index: 1;
}
.contact-item { display: flex; flex-direction: column; gap: 4px; }
.contact-item-label {
  font-size: 12px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: rgba(255,255,255,0.6);
}
.contact-item-val {
  font-size: 17px;
  font-weight: 700;
  color: var(--white);
  text-decoration: none;
  transition: color 0.2s;
}
.contact-item-val:hover { color: var(--olive-lt); }

/* ── FOOTER ─────────────────────────────────────── */
footer {
  background: var(--bg-dark);
  padding: 28px 48px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  border-top: 4px solid var(--olive);
}

.footer-logo {
  font-size: 17px;
  font-weight: 700;
  letter-spacing: 0.12em;
  color: rgba(255,255,255,0.5);
  text-transform: uppercase;
}
.footer-logo span { color: var(--olive-lt); }
footer p { font-size: 12px; color: rgba(255,255,255,0.5); }

/* ── MODAL ──────────────────────────────────────── */
.modal-overlay {
  position: fixed;
  inset: 0;
  z-index: 999;
  background: rgba(37,41,36,0.75);
  backdrop-filter: blur(6px);
  -webkit-backdrop-filter: blur(6px);
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 24px;
  opacity: 0;
  visibility: hidden;
  transition: opacity 0.3s, visibility 0.3s;
}
.modal-overlay.active { opacity: 1; visibility: visible; }

.modal {
  background: var(--white);
  border-radius: 3px;
  width: 100%;
  max-width: 560px;
  max-height: 90vh;
  overflow-y: auto;
  position: relative;
  box-shadow: 0 24px 64px rgba(0,0,0,0.35);
}

.modal-header {
  background: var(--bg-dark);
  padding: 32px 40px 28px;
  position: relative;
  overflow: hidden;
}
.modal-header::after {
  content: '';
  position: absolute;
  top: 0; right: 0;
  width: 80px;
  height: 100%;
  background-image: repeating-linear-gradient(
    -45deg,
    rgba(107,122,74,0.18) 0px,
    rgba(107,122,74,0.18) 10px,
    transparent 10px,
    transparent 22px
  );
  mask-image: linear-gradient(to left, rgba(0,0,0,0.5) 0%, transparent 100%);
  -webkit-mask-image: linear-gradient(to left, rgba(0,0,0,0.5) 0%, transparent 100%);
  pointer-events: none;
}

.modal-header .modal-eyebrow {
  font-size: 12px;
  font-weight: 500;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: rgba(255,255,255,0.5);
  margin-bottom: 8px;
  position: relative;
  z-index: 1;
}
.modal-header h3 {
  font-size: 22px;
  font-weight: 700;
  color: var(--white);
  text-transform: uppercase;
  letter-spacing: 0.03em;
  line-height: 1.2;
  position: relative;
  z-index: 1;
}

.modal-close {
  position: absolute;
  top: 16px; right: 16px;
  z-index: 2;
  width: 36px; height: 36px;
  background: none;
  border: none;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  color: rgba(255,255,255,0.5);
  transition: color 0.2s;
}
.modal-close:hover { color: var(--white); }
.modal-close svg { width: 20px; height: 20px; }

.modal-body { padding: 36px 40px 40px; }
.modal-form { display: flex; flex-direction: column; gap: 20px; }

.form-group { display: flex; flex-direction: column; gap: 6px; }
.form-group label {
  font-size: 12px;
  font-weight: 500;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--text-dim);
}
.form-group label .required { color: var(--olive); }
.form-group input {
  font-family: 'Ubuntu', sans-serif;
  font-size: 15px;
  padding: 12px 14px;
  border: 1px solid rgba(37,41,36,0.15);
  border-radius: 2px;
  background: var(--white);
  color: var(--text);
  transition: border-color 0.2s, box-shadow 0.2s;
  outline: none;
  width: 100%;
}
.form-group input:focus {
  border-color: var(--olive);
  box-shadow: 0 0 0 3px rgba(62,73,25,0.08);
}
.form-group input.error { border-color: var(--error); }
.form-group .field-error {
  font-size: 12px;
  color: var(--error);
  display: none;
}
.form-group .field-error.visible { display: block; }

.checkbox-group {
  display: flex;
  align-items: flex-start;
  gap: 10px;
  margin-top: 2px;
}
.checkbox-group input[type="checkbox"] {
  appearance: none;
  -webkit-appearance: none;
  width: 18px; height: 18px;
  min-width: 18px;
  border: 1.5px solid rgba(37,41,36,0.25);
  border-radius: 2px;
  background: var(--white);
  cursor: pointer;
  position: relative;
  margin-top: 1px;
  transition: border-color 0.2s, background 0.2s;
}
.checkbox-group input[type="checkbox"]:checked {
  background: var(--olive);
  border-color: var(--olive);
}
.checkbox-group input[type="checkbox"]:checked::after {
  content: '';
  position: absolute;
  left: 5px; top: 2px;
  width: 6px; height: 10px;
  border: solid var(--white);
  border-width: 0 2px 2px 0;
  transform: rotate(45deg);
}
.checkbox-group input[type="checkbox"].error { border-color: var(--error); }
.checkbox-group .field-error { margin-top: -12px; }
.checkbox-group label {
  font-size: 13px;
  color: var(--text-dim);
  line-height: 1.55;
  cursor: pointer;
  user-select: none;
}
.checkbox-group label a {
  color: var(--olive);
  text-decoration: none;
  border-bottom: 1px solid var(--olive-lt);
  transition: color 0.2s, border-color 0.2s;
}
.checkbox-group label a:hover { color: var(--bg-dark); border-color: var(--bg-dark); }

.modal-submit {
  display: inline-block;
  background: var(--olive);
  color: var(--white);
  font-family: 'Ubuntu', sans-serif;
  font-size: 15px;
  font-weight: 700;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  padding: 16px 36px;
  text-decoration: none;
  border-radius: 2px;
  border: none;
  cursor: pointer;
  transition: background 0.2s, transform 0.15s;
  width: 100%;
  margin-top: 4px;
}
.modal-submit:hover { background: var(--bg-dark); transform: translateY(-1px); }
.modal-submit:disabled { opacity: 0.6; cursor: not-allowed; transform: none; }

.modal-success {
  display: none;
  text-align: center;
  padding: 48px 40px;
}
.modal-success.visible { display: block; }
.modal-success .success-icon {
  width: 48px; height: 48px;
  margin: 0 auto 20px;
  color: var(--olive);
}
.modal-success h3 {
  font-size: 20px;
  font-weight: 700;
  color: var(--bg-dark);
  text-transform: uppercase;
  letter-spacing: 0.03em;
  margin-bottom: 10px;
}
.modal-success p {
  font-size: 14px;
  color: var(--text-dim);
  line-height: 1.7;
  margin-bottom: 28px;
}
.modal-success .btn-close-success {
  display: inline-block;
  color: var(--olive);
  font-size: 14px;
  font-weight: 500;
  text-decoration: none;
  border-bottom: 1px solid var(--olive-lt);
  padding-bottom: 2px;
  transition: color 0.2s, border-color 0.2s;
  cursor: pointer;
  background: none;
  border-top: none;
  border-left: none;
  border-right: none;
}
.modal-success .btn-close-success:hover { color: var(--bg-dark); border-color: var(--bg-dark); }

.modal-submit .spinner {
  display: none;
  width: 18px; height: 18px;
  border: 2px solid rgba(255,255,255,0.3);
  border-top-color: var(--white);
  border-radius: 50%;
  animation: spin 0.7s linear infinite;
  margin-right: 10px;
  vertical-align: middle;
}
.modal-submit.sending .spinner { display: inline-block; }
.modal-submit.sending .submit-text { display: none; }
@keyframes spin { to { transform: rotate(360deg); } }

/* ================================================================
   RESPONSIVE
   ================================================================ */

/* Tablet + Mobile (≤900px) */
@media (max-width: 900px) {
  nav { padding: 0 20px; }
  section { padding: 64px 20px; }
  .hero { padding: 96px 20px 64px; }

  .nav-cta-top { font-size: 11px; padding: 6px 14px; }

  .burger { display: flex; }

  .problem-grid,
  .results-grid,
  .tech-layout,
  .benefits-grid,
  .price-layout { grid-template-columns: 1fr; }

  .results-card { padding: 28px 24px; }

  .hero-stats { gap: 28px; }
  .stat-num { font-size: 32px; }

  .hero-actions { flex-direction: column; align-items: flex-start; }
  .hero-actions .btn-primary { width: 100%; text-align: center; }

  .price-section { padding: 64px 20px 80px; }
  .price-layout { gap: 32px; }

  .tech-layout { gap: 40px; }
  .tech-diagram { padding: 28px; }

  .contact-section { padding: 64px 20px; }
  .contact-meta { gap: 24px; }
  .contact-item { align-items: center; }

  footer { flex-direction: column; gap: 10px; text-align: center; padding: 24px 20px; }

  .modal-overlay { padding: 12px; }
  .modal { max-width: 100%; }
  .modal-header { padding: 24px 24px 20px; }
  .modal-header h3 { font-size: 18px; }
  .modal-body { padding: 24px; }
  .modal-success { padding: 36px 20px; }
}

/* Small phones (≤480px) */
@media (max-width: 480px) {
  .hero h1 { font-size: 30px; }
  .hero-sub { font-size: 15px; }
  .hero-stats { flex-direction: column; gap: 20px; }
  .hero-stats { margin-top: 48px; padding-top: 28px; }

  h2 { font-size: 24px; }
  section { padding: 48px 16px; }
  .hero { padding: 80px 16px 48px; }

  .price-amount { font-size: 42px; }
  .price-card { padding: 32px; }

  .contact-actions { flex-direction: column; }
  .btn-white { width: 100%; text-align: center; }

  .nav-drawer { width: 100%; }
}

/* ================================================================
   DEMO VIDEO (секция из трансфера, адаптирована к дизайну проекта)
   ================================================================ */
.demo-video-section { background: var(--bg); }

.demo-video-layout {
  display: grid;
  grid-template-columns: 1fr 1.1fr;
  gap: 72px;
  align-items: center;
}

.demo-copy {
  font-size: 14px;
  color: var(--text-dim);
  line-height: 1.75;
  max-width: 520px;
  margin-top: 20px;
}

/* Статы — display-числа (dl/dt/dd) */
.demo-stats {
  display: grid;
  grid-template-columns: 1fr 1fr;
  max-width: 540px;
  margin-top: 36px;
  border: 1px solid var(--border);
}
.demo-stats div {
  padding: 24px;
  border-right: 1px solid var(--border);
}
.demo-stats div:last-child { border-right: 0; }
.demo-stats dt {
  font-size: 28px;
  font-weight: 700;
  color: var(--olive);
  line-height: 1;
}
.demo-stats dd {
  font-size: 12px;
  text-transform: uppercase;
  letter-spacing: 0.11em;
  color: var(--text-dim);
  margin-top: 8px;
}

/* Видеокарточка: тёмный блок, видео + подпись */
.demo-video-card {
  background: var(--bg-dark);
  border-radius: 3px;
  overflow: hidden;
  margin: 0;
  align-self: center;
}
.demo-video-card video {
  display: block;
  width: 100%;
  max-height: 540px;
  object-fit: cover;
}
.demo-video-card figcaption { padding: 20px 24px; }
.demo-video-card small,
.demo-video-card strong { display: block; }
.demo-video-card small {
  font-size: 12px;
  text-transform: uppercase;
  letter-spacing: 0.15em;
  color: var(--olive-lt);
  margin-bottom: 8px;
}
.demo-video-card strong {
  font-size: 14px;
  font-weight: 700;
  color: var(--white);
}

/* ================================================================
   FAQ (нативные details/summary, без JS; тексты 1:1 с JSON-LD)
   ================================================================ */
.faq-section { background: var(--white); }

.faq-layout {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 72px;
  align-items: start;
}

.faq-list { border-top: 1px solid var(--border); }
.faq-list details { border-bottom: 1px solid var(--border); }

.faq-list summary {
  cursor: pointer;
  padding: 24px 48px 24px 0;
  font-size: 16px;
  font-weight: 700;
  color: var(--text);
  list-style: none;
  position: relative;
}
.faq-list summary::-webkit-details-marker { display: none; }
.faq-list summary::after {
  content: '+';
  position: absolute;
  right: 0;
  top: 50%;
  transform: translateY(-50%);
  font-size: 24px;
  font-weight: 300;
  color: var(--olive);
}
.faq-list details[open] summary::after { content: '−'; }

.faq-list details p {
  margin: 0;
  padding: 0 48px 24px 0;
  font-size: 13px;
  color: var(--text-dim);
  line-height: 1.7;
}

/* ================================================================
   Адаптив новых секций
   ================================================================ */
@media (max-width: 900px) {
  .demo-video-layout,
  .faq-layout { grid-template-columns: 1fr; gap: 40px; }
  .demo-stats { max-width: 100%; }
}

@media (max-width: 480px) {
  .demo-stats { grid-template-columns: 1fr; }
  .demo-stats div {
    border-bottom: 1px solid var(--border);
    border-right: 0;
  }
  .demo-stats div:last-child { border-bottom: 0; }
}