/* ============================================================
   Aqua Rezerv - промышленный B2B лэндинг
   Палитра: белый/светло-серый + синий #1B7FD4 + графит #1c2530
   ============================================================ */

:root {
  --blue: #1B7FD4;
  --blue-2: #2384D6;
  --blue-dark: #14639f;
  --blue-soft: #EAF3FB;
  --ink: #1c2530;
  --ink-soft: #5b6b7c;
  --line: #e3e9ef;
  --bg: #ffffff;
  --bg-tint: #f5f8fb;
  --green: #25D366;
  --green-dark: #1eb457;
  --radius: 16px;
  --shadow: 0 8px 30px rgba(20, 45, 75, 0.08);
  --shadow-hover: 0 14px 40px rgba(20, 45, 75, 0.14);
  --font: 'Manrope', system-ui, -apple-system, 'Segoe UI', sans-serif;
}

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

html { scroll-behavior: smooth; }

body {
  font-family: var(--font);
  color: var(--ink);
  background: var(--bg);
  line-height: 1.6;
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

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

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

ul, ol { list-style: none; }

/* ---------- Контейнеры ---------- */
.container {
  width: 100%;
  max-width: 1160px;
  margin: 0 auto;
  padding: 0 20px;
  min-width: 0;
}
.container--narrow { max-width: 820px; }

/* ---------- Кнопки ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  padding: 13px 26px;
  border-radius: 12px;
  font-weight: 700;
  font-size: 15px;
  line-height: 1.2;
  border: 2px solid transparent;
  cursor: pointer;
  transition: transform 0.2s ease, box-shadow 0.2s ease, background 0.2s ease, color 0.2s ease, border-color 0.2s ease;
  text-align: center;
}
.btn:active { transform: scale(0.98); }

.btn--primary {
  background: linear-gradient(135deg, var(--blue-2), var(--blue-dark));
  color: #fff;
  box-shadow: 0 6px 20px rgba(27, 127, 212, 0.35);
}
.btn--primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 10px 28px rgba(27, 127, 212, 0.45);
}

.btn--ghost {
  background: #fff;
  color: var(--blue);
  border-color: rgba(27, 127, 212, 0.35);
}
.btn--ghost:hover {
  border-color: var(--blue);
  background: var(--blue-soft);
  transform: translateY(-2px);
}

.btn--outline {
  background: transparent;
  color: var(--blue);
  border-color: rgba(27, 127, 212, 0.4);
  padding: 11px 20px;
  font-size: 14px;
}
.btn--outline:hover {
  background: var(--blue);
  color: #fff;
  border-color: var(--blue);
}

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

/* ---------- Шапка ---------- */
.header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(255, 255, 255, 0.92);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  transition: box-shadow 0.3s ease;
}
.header.is-scrolled { box-shadow: 0 4px 24px rgba(20, 45, 75, 0.1); }

.header__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  height: 72px;
}

.header__logo img {
  height: 52px;
  width: auto;
  transition: transform 0.25s ease;
}
.header__logo:hover img { transform: scale(1.04); }

.header__nav {
  display: flex;
  align-items: center;
  gap: 26px;
}

.header__link {
  font-weight: 600;
  font-size: 14.5px;
  color: var(--ink-soft);
  position: relative;
  transition: color 0.2s ease;
  padding: 6px 0;
}
.header__link::after {
  content: '';
  position: absolute;
  left: 0;
  bottom: 0;
  width: 0;
  height: 2px;
  background: var(--blue);
  border-radius: 2px;
  transition: width 0.25s ease;
}
.header__link:hover { color: var(--ink); }
.header__link:hover::after { width: 100%; }

.header__cta { padding: 10px 20px; font-size: 14px; }

/* Бургер */
.burger {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 44px;
  height: 44px;
  padding: 10px;
  background: transparent;
  border: none;
  cursor: pointer;
  z-index: 110;
}
.burger span {
  display: block;
  height: 2.5px;
  width: 100%;
  background: var(--ink);
  border-radius: 2px;
  transition: transform 0.3s ease, opacity 0.3s ease;
}
.burger.is-open span:nth-child(1) { transform: translateY(7.5px) rotate(45deg); }
.burger.is-open span:nth-child(2) { opacity: 0; }
.burger.is-open span:nth-child(3) { transform: translateY(-7.5px) rotate(-45deg); }

/* ---------- Hero ---------- */
.hero {
  position: relative;
  padding: 64px 0 96px;
  background: linear-gradient(180deg, #f7fafd 0%, #eef4fa 100%);
  overflow: hidden;
}

.hero__bg {
  position: absolute;
  inset: 0;
  pointer-events: none;
}
.hero__wave {
  position: absolute;
  left: 0;
  right: 0;
  bottom: -2px;
  width: 100%;
  height: 140px;
  color: #ffffff;
}

.hero__inner {
  position: relative;
  display: grid;
  grid-template-columns: minmax(0, 1.15fr) minmax(0, 0.85fr);
  gap: 48px;
  align-items: center;
}

.hero__eyebrow {
  display: inline-block;
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--blue);
  background: rgba(27, 127, 212, 0.1);
  border: 1px solid rgba(27, 127, 212, 0.2);
  border-radius: 999px;
  padding: 7px 16px;
  margin-bottom: 22px;
}

.hero__title {
  font-size: clamp(30px, 5vw, 48px);
  font-weight: 800;
  line-height: 1.14;
  letter-spacing: -0.02em;
  margin-bottom: 18px;
}
.accent { color: var(--blue); }

.hero__subtitle {
  font-size: clamp(16px, 2vw, 18px);
  color: var(--ink-soft);
  max-width: 560px;
  margin-bottom: 30px;
}

.hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
  margin-bottom: 36px;
}

.hero__facts {
  display: flex;
  flex-wrap: wrap;
  gap: 12px 28px;
}
.hero__facts li {
  display: flex;
  align-items: center;
  gap: 9px;
  font-size: 14px;
  font-weight: 600;
  color: var(--ink-soft);
  min-width: 0;
}
.hero__facts svg {
  width: 20px;
  height: 20px;
  flex-shrink: 0;
  color: var(--blue);
}

.hero__visual { min-width: 0; }
.hero__tank {
  width: 100%;
  max-width: 420px;
  margin: 0 auto;
  filter: drop-shadow(0 20px 40px rgba(27, 127, 212, 0.15));
  animation: float 6s ease-in-out infinite;
}
.hero__tanks {
  width: 100%;
  max-width: 540px;
  margin: 0 auto;
  filter: drop-shadow(0 22px 40px rgba(27, 127, 212, 0.22));
}
@keyframes float {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-10px); }
}

/* ---------- Секции ---------- */
.section { padding: 84px 0; }
.section--tint { background: var(--bg-tint); }

.section__head {
  max-width: 680px;
  margin-bottom: 48px;
}
.section__eyebrow {
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--blue);
  margin-bottom: 10px;
}
.section__title {
  font-size: clamp(25px, 3.6vw, 36px);
  font-weight: 800;
  line-height: 1.2;
  letter-spacing: -0.015em;
}
.section__lead {
  margin-top: 14px;
  color: var(--ink-soft);
  font-size: 16.5px;
}

/* ---------- Продукция ---------- */
.products__grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 22px;
}

.product {
  position: relative;
  display: flex;
  flex-direction: column;
  min-width: 0;
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 24px;
  transition: transform 0.28s ease, box-shadow 0.28s ease, border-color 0.28s ease;
  scroll-margin-top: 90px;
}
.product:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-hover);
  border-color: rgba(27, 127, 212, 0.35);
}

.product__media {
  aspect-ratio: 3 / 2;
  border-radius: 12px;
  background:
    radial-gradient(120% 140% at 85% 15%, rgba(27, 127, 212, 0.16), transparent 55%),
    linear-gradient(145deg, #f0f6fc 0%, #e2edf7 100%);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 18px;
  color: var(--blue);
  overflow: hidden;
}
.product__media svg {
  width: 54px;
  height: 54px;
  transition: transform 0.3s ease;
}
.product:hover .product__media svg { transform: scale(1.12); }
.product__media img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: center;
  transition: transform 0.4s ease;
}
.product:hover .product__media img { transform: scale(1.06); }

.product__title {
  font-size: 17px;
  font-weight: 800;
  line-height: 1.3;
  margin-bottom: 10px;
}
.product__text {
  font-size: 14px;
  color: var(--ink-soft);
  flex-grow: 1;
  margin-bottom: 18px;
}
.product__btn { width: 100%; }

/* Ключевая карточка */
.product--key {
  border-color: rgba(27, 127, 212, 0.45);
  background: linear-gradient(180deg, #ffffff 0%, #f2f8fd 100%);
}
.product__badge {
  position: absolute;
  top: 14px;
  right: 14px;
  z-index: 1;
  font-size: 11px;
  font-weight: 800;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  color: #fff;
  background: linear-gradient(135deg, var(--blue-2), var(--blue-dark));
  border-radius: 999px;
  padding: 5px 12px;
}
.product__media--featured {
  background:
    radial-gradient(120% 140% at 85% 15%, rgba(27, 127, 212, 0.3), transparent 60%),
    linear-gradient(145deg, #dcebf8 0%, #c9e0f4 100%);
}
/* Техническая схема — показываем целиком, не обрезая подписи */
.product__media--diagram {
  aspect-ratio: 4 / 5;
  background: linear-gradient(160deg, #f4f7fa 0%, #e9f0f6 100%);
}
.product__media--diagram img {
  object-fit: contain;
  padding: 10px;
}
.product:hover .product__media--diagram img { transform: scale(1.03); }

/* ---------- Этапы ---------- */
.process__grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 22px;
  counter-reset: step;
}

.step {
  position: relative;
  min-width: 0;
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 28px 24px 24px;
  transition: transform 0.28s ease, box-shadow 0.28s ease;
}
.step:hover {
  transform: translateY(-5px);
  box-shadow: var(--shadow);
}

.step__num {
  position: absolute;
  top: 18px;
  right: 20px;
  font-size: 34px;
  font-weight: 800;
  color: rgba(27, 127, 212, 0.14);
  line-height: 1;
}

.step__icon {
  width: 52px;
  height: 52px;
  border-radius: 13px;
  background: var(--blue-soft);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--blue);
  margin-bottom: 18px;
}
.step__icon svg { width: 27px; height: 27px; }

.step__title {
  font-size: 17px;
  font-weight: 800;
  margin-bottom: 8px;
}
.step__text {
  font-size: 14px;
  color: var(--ink-soft);
}

/* ---------- Преимущества ---------- */
.advantages__grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 22px;
}

.advantage {
  min-width: 0;
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 26px 24px;
  transition: transform 0.28s ease, box-shadow 0.28s ease, border-color 0.28s ease;
}
.advantage:hover {
  transform: translateY(-5px);
  box-shadow: var(--shadow);
  border-color: rgba(27, 127, 212, 0.3);
}

.advantage__icon {
  width: 50px;
  height: 50px;
  border-radius: 13px;
  background: linear-gradient(135deg, rgba(27, 127, 212, 0.12), rgba(27, 127, 212, 0.05));
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--blue);
  margin-bottom: 16px;
}
.advantage__icon svg { width: 26px; height: 26px; }

.advantage h3 {
  font-size: 16.5px;
  font-weight: 800;
  margin-bottom: 7px;
}
.advantage p {
  font-size: 14px;
  color: var(--ink-soft);
}

/* ---------- Наши работы ---------- */
.counters {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 22px;
  margin-bottom: 44px;
}

.counter {
  min-width: 0;
  background: linear-gradient(135deg, var(--blue-2), var(--blue-dark));
  border-radius: var(--radius);
  padding: 26px 20px;
  text-align: center;
  color: #fff;
  box-shadow: 0 10px 30px rgba(27, 127, 212, 0.25);
}
.counter__num {
  display: block;
  font-size: clamp(30px, 4.5vw, 44px);
  font-weight: 800;
  line-height: 1.1;
  letter-spacing: -0.02em;
}
.counter__num::after { content: '+'; opacity: 0.7; }
.counter__label {
  display: block;
  margin-top: 6px;
  font-size: 13.5px;
  font-weight: 600;
  opacity: 0.9;
}

.projects__grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 22px;
}

.project {
  min-width: 0;
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
  transition: transform 0.28s ease, box-shadow 0.28s ease;
}
.project:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-hover);
}

.project__media {
  position: relative;
  height: 170px;
  background:
    radial-gradient(130% 150% at 15% 10%, rgba(27, 127, 212, 0.22), transparent 55%),
    linear-gradient(160deg, #e6f0f9 0%, #d3e5f4 100%);
  display: flex;
  align-items: center;
  justify-content: center;
  color: rgba(27, 127, 212, 0.7);
}
.project__media svg { width: 64px; height: 64px; }
.project__media img {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.5s ease;
}
.project:hover .project__media img { transform: scale(1.05); }

.project__tag {
  position: absolute;
  top: 12px;
  left: 12px;
  z-index: 1;
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  background: rgba(255, 255, 255, 0.9);
  color: var(--ink-soft);
  border-radius: 999px;
  padding: 4px 11px;
}

.project figcaption { padding: 20px 22px 24px; }
.project h3 {
  font-size: 16px;
  font-weight: 800;
  margin-bottom: 7px;
  line-height: 1.35;
}
.project p {
  font-size: 13.5px;
  color: var(--ink-soft);
}

/* ---------- FAQ ---------- */
.faq__list {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.faq__item {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 14px;
  overflow: hidden;
  transition: border-color 0.25s ease, box-shadow 0.25s ease;
}
.faq__item[open] {
  border-color: rgba(27, 127, 212, 0.4);
  box-shadow: var(--shadow);
}

.faq__item summary {
  list-style: none;
  cursor: pointer;
  padding: 18px 52px 18px 22px;
  font-weight: 700;
  font-size: 15.5px;
  position: relative;
  transition: color 0.2s ease;
}
.faq__item summary::-webkit-details-marker { display: none; }
.faq__item summary:hover { color: var(--blue); }

.faq__item summary::after {
  content: '';
  position: absolute;
  right: 20px;
  top: 50%;
  width: 10px;
  height: 10px;
  border-right: 2.5px solid var(--blue);
  border-bottom: 2.5px solid var(--blue);
  transform: translateY(-70%) rotate(45deg);
  transition: transform 0.3s ease;
}
.faq__item[open] summary::after {
  transform: translateY(-30%) rotate(-135deg);
}

.faq__item p {
  padding: 0 22px 20px;
  font-size: 14.5px;
  color: var(--ink-soft);
}

/* ---------- Заявка ---------- */
.section--cta {
  background:
    radial-gradient(90% 120% at 90% 0%, rgba(27, 127, 212, 0.12), transparent 55%),
    linear-gradient(180deg, #f2f7fc 0%, #e8f1f9 100%);
}

.cta-card {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 22px;
  box-shadow: var(--shadow);
  padding: clamp(28px, 5vw, 48px);
}
.cta-card__head {
  text-align: center;
  max-width: 540px;
  margin: 0 auto 32px;
}

.form {
  display: flex;
  flex-direction: column;
  gap: 18px;
  max-width: 560px;
  margin: 0 auto;
}

.form__row {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 18px;
}

.form__field {
  display: flex;
  flex-direction: column;
  gap: 7px;
  min-width: 0;
}
.form__label {
  font-size: 13.5px;
  font-weight: 700;
  color: var(--ink);
}

.form input,
.form select {
  width: 100%;
  min-width: 0;
  font-family: var(--font);
  font-size: 15px;
  color: var(--ink);
  background: var(--bg-tint);
  border: 1.5px solid var(--line);
  border-radius: 11px;
  padding: 13px 16px;
  transition: border-color 0.2s ease, background 0.2s ease, box-shadow 0.2s ease;
  appearance: none;
  -webkit-appearance: none;
}
.form select {
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='8'%3E%3Cpath d='M1 1l5 5 5-5' stroke='%235b6b7c' stroke-width='2' fill='none' stroke-linecap='round'/%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right 16px center;
  padding-right: 40px;
  cursor: pointer;
}
.form input:focus,
.form select:focus {
  outline: none;
  border-color: var(--blue);
  background: #fff;
  box-shadow: 0 0 0 4px rgba(27, 127, 212, 0.12);
}
.form input.is-invalid,
.form select.is-invalid {
  border-color: #d84a4a;
  background: #fdf3f3;
}

.form__error {
  font-size: 13.5px;
  color: #c33;
  font-weight: 600;
  text-align: center;
}

.form__submit {
  background: linear-gradient(135deg, var(--green), var(--green-dark));
  box-shadow: 0 8px 24px rgba(37, 211, 102, 0.35);
}
.form__submit:hover { box-shadow: 0 12px 30px rgba(37, 211, 102, 0.45); }
.form__submit svg { width: 21px; height: 21px; }

.form__hint {
  font-size: 12.5px;
  color: var(--ink-soft);
  text-align: center;
}

/* ---------- Контакты ---------- */
.contacts__grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 20px;
}

.contact {
  display: flex;
  align-items: center;
  gap: 15px;
  min-width: 0;
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 20px;
  transition: transform 0.25s ease, box-shadow 0.25s ease, border-color 0.25s ease;
}
a.contact:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow);
  border-color: rgba(27, 127, 212, 0.35);
}

.contact__icon {
  flex-shrink: 0;
  width: 48px;
  height: 48px;
  border-radius: 12px;
  background: var(--blue-soft);
  color: var(--blue);
  display: flex;
  align-items: center;
  justify-content: center;
}
.contact__icon svg { width: 24px; height: 24px; }
.contact__icon--wa {
  background: rgba(37, 211, 102, 0.14);
  color: var(--green-dark);
}

.contact > div:last-child { min-width: 0; }
.contact__label {
  display: block;
  font-size: 12px;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--ink-soft);
}
.contact__value {
  display: block;
  font-size: 15px;
  font-weight: 700;
  overflow-wrap: break-word;
}
/* email длиннее прочих — чуть уменьшаем, чтобы влезал в одну строку и не рвался на «z» */
.contact__value--email {
  font-size: 13px;
  letter-spacing: -0.2px;
  white-space: nowrap;
}
@media (max-width: 360px) {
  .contact__value--email { font-size: 12px; white-space: normal; overflow-wrap: anywhere; }
}
.contact__hint {
  display: block;
  margin-top: 3px;
  font-size: 12.5px;
  font-weight: 600;
  color: var(--blue);
}
a.contact:hover .contact__hint { text-decoration: underline; }

/* ---------- Футер ---------- */
.footer {
  background: #f0f4f8;
  border-top: 1px solid var(--line);
  padding-top: 56px;
}

.footer__inner {
  display: grid;
  grid-template-columns: minmax(0, 1.3fr) repeat(3, minmax(0, 1fr));
  gap: 36px;
  padding-bottom: 40px;
}

.footer__brand p {
  font-size: 14px;
  color: var(--ink-soft);
  max-width: 260px;
}
.footer__logo {
  display: inline-block;
  margin-bottom: 16px;
}
.footer__logo img { height: 64px; width: auto; }

.footer__nav {
  display: flex;
  flex-direction: column;
  gap: 10px;
  min-width: 0;
}
.footer__head {
  font-size: 13px;
  font-weight: 800;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--ink);
  margin-bottom: 4px;
}
.footer__nav a {
  font-size: 14px;
  color: var(--ink-soft);
  transition: color 0.2s ease;
  overflow-wrap: break-word;
}
.footer__nav a:hover { color: var(--blue); }
.footer__addr { font-size: 14px; color: var(--ink-soft); }

.footer__bottom {
  border-top: 1px solid var(--line);
  padding-top: 20px;
  padding-bottom: 20px;
}
.footer__bottom p {
  font-size: 13px;
  color: var(--ink-soft);
}

/* ---------- Липкая кнопка WhatsApp ---------- */
.wa-float {
  position: fixed;
  right: 20px;
  bottom: 20px;
  z-index: 90;
  width: 60px;
  height: 60px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--green), var(--green-dark));
  color: #fff;
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: 0 8px 26px rgba(37, 211, 102, 0.45);
  transition: transform 0.25s ease, box-shadow 0.25s ease;
  animation: wa-pulse 2.6s ease-out infinite;
}
.wa-float svg { width: 32px; height: 32px; }
.wa-float:hover {
  transform: scale(1.08);
  box-shadow: 0 12px 32px rgba(37, 211, 102, 0.55);
}
@keyframes wa-pulse {
  0% { box-shadow: 0 8px 26px rgba(37, 211, 102, 0.45), 0 0 0 0 rgba(37, 211, 102, 0.4); }
  70% { box-shadow: 0 8px 26px rgba(37, 211, 102, 0.45), 0 0 0 18px rgba(37, 211, 102, 0); }
  100% { box-shadow: 0 8px 26px rgba(37, 211, 102, 0.45), 0 0 0 0 rgba(37, 211, 102, 0); }
}

/* ---------- Сертификаты ---------- */
.certs__grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 22px;
}

.cert {
  min-width: 0;
  display: block;
  width: 100%;
  padding: 0;
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 12px;
  overflow: hidden;
  cursor: pointer;
  box-shadow: var(--shadow);
  transition: transform 0.28s ease, box-shadow 0.28s ease, border-color 0.28s ease;
}
.cert:hover,
.cert:focus-visible {
  transform: translateY(-5px);
  box-shadow: var(--shadow-hover);
  border-color: rgba(27, 127, 212, 0.4);
  outline: none;
}
.cert img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 1 / 1.414;
  object-fit: contain;
  background: #fff;
  transition: transform 0.4s ease;
}
.cert:hover img { transform: scale(1.04); }

/* ---------- Лайтбокс ---------- */
.lightbox {
  position: fixed;
  inset: 0;
  z-index: 200;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 24px;
  background: rgba(15, 25, 35, 0.86);
  -webkit-backdrop-filter: blur(4px);
  backdrop-filter: blur(4px);
  overflow-y: auto;
  opacity: 0;
  visibility: hidden;
  transition: opacity 0.3s ease, visibility 0.3s ease;
}
.lightbox.is-open { opacity: 1; visibility: visible; }

.lightbox__img {
  max-width: min(92vw, 680px);
  max-height: 90vh;
  width: auto;
  height: auto;
  object-fit: contain;
  border-radius: 6px;
  box-shadow: 0 24px 70px rgba(0, 0, 0, 0.5);
  background: #fff;
}
.lightbox.is-open .lightbox__img { animation: lb-pop 0.3s ease; }
@keyframes lb-pop {
  from { opacity: 0; transform: scale(0.96); }
  to { opacity: 1; transform: scale(1); }
}

.lightbox__btn {
  position: absolute;
  display: flex;
  align-items: center;
  justify-content: center;
  width: 46px;
  height: 46px;
  border: none;
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.16);
  color: #fff;
  cursor: pointer;
  transition: background 0.2s ease, transform 0.2s ease;
}
.lightbox__btn:hover { background: rgba(255, 255, 255, 0.3); transform: scale(1.06); }
.lightbox__btn svg { width: 24px; height: 24px; }
.lightbox__close { top: 18px; right: 18px; }
.lightbox__nav { top: 50%; transform: translateY(-50%); }
.lightbox__nav:hover { transform: translateY(-50%) scale(1.06); }
.lightbox__nav--prev { left: 18px; }
.lightbox__nav--next { right: 18px; }

/* ---------- Scroll-reveal ---------- */
.reveal {
  opacity: 0;
  transform: translateY(26px);
  transition: opacity 0.7s ease, transform 0.7s ease;
}
.reveal.is-visible {
  opacity: 1;
  transform: translateY(0);
}
.reveal--delay { transition-delay: 0.15s; }

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .reveal { opacity: 1; transform: none; transition: none; }
  .hero__tank { animation: none; }
  .wa-float { animation: none; }
}

/* Якорная прокрутка с учётом липкой шапки */
section[id], [id] { scroll-margin-top: 86px; }

/* ============================================================
   Адаптив
   ============================================================ */

@media (max-width: 1024px) {
  .products__grid { grid-template-columns: repeat(3, minmax(0, 1fr)); }
  .process__grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .contacts__grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .footer__inner { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .certs__grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}

@media (max-width: 860px) {
  .hero__inner { grid-template-columns: minmax(0, 1fr); gap: 36px; }
  .hero__visual { order: -1; }
  .hero__tank { max-width: 300px; }
  .hero__tanks { max-width: 360px; }
  .hero { padding: 40px 0 80px; }
  .products__grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .advantages__grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .projects__grid { grid-template-columns: minmax(0, 1fr); }
  .section { padding: 64px 0; }

  /* Мобильное меню */
  .burger { display: flex; }
  /* ФИКС: backdrop-filter делал шапку containing block для fixed-меню (drawer),
     из-за чего меню сжималось по высоте шапки. Убираем blur на мобиле. */
  .header {
    backdrop-filter: none;
    -webkit-backdrop-filter: none;
    background: rgba(255, 255, 255, 0.97);
  }
  .header__nav {
    position: fixed;
    top: 0;
    right: 0;
    bottom: 0;
    width: min(320px, 85vw);
    background: #fff;
    flex-direction: column;
    align-items: flex-start;
    justify-content: flex-start;
    gap: 8px;
    padding: 96px 28px 28px;
    box-shadow: -12px 0 40px rgba(20, 45, 75, 0.15);
    transform: translateX(105%);
    transition: transform 0.35s cubic-bezier(0.22, 1, 0.36, 1);
    overflow-y: auto;
  }
  .header__nav.is-open { transform: translateX(0); }
  .header__link {
    font-size: 17px;
    color: var(--ink);
    padding: 10px 0;
    width: 100%;
    border-bottom: 1px solid var(--bg-tint);
  }
  .header__cta {
    margin-top: 14px;
    width: 100%;
    padding: 14px 20px;
    font-size: 15px;
  }

  .nav-overlay {
    position: fixed;
    inset: 0;
    background: rgba(28, 37, 48, 0.45);
    z-index: 99;
    opacity: 0;
    pointer-events: none;
    transition: opacity 0.3s ease;
  }
  .nav-overlay.is-open { opacity: 1; pointer-events: auto; }
}

@media (max-width: 560px) {
  .products__grid { grid-template-columns: minmax(0, 1fr); }
  .process__grid { grid-template-columns: minmax(0, 1fr); }
  .advantages__grid { grid-template-columns: minmax(0, 1fr); }
  .counters { grid-template-columns: minmax(0, 1fr); gap: 14px; }
  .contacts__grid { grid-template-columns: minmax(0, 1fr); }
  .footer__inner { grid-template-columns: minmax(0, 1fr); gap: 28px; }
  .form__row { grid-template-columns: minmax(0, 1fr); }
  .hero__actions .btn { width: 100%; }
  .header__logo img { height: 44px; }
  .header__inner { height: 64px; }
  .wa-float { width: 54px; height: 54px; right: 16px; bottom: 16px; }
  .wa-float svg { width: 29px; height: 29px; }

  .lightbox { padding: 16px; }
  .lightbox__img { max-width: 94vw; max-height: 78vh; }
  .lightbox__nav { top: auto; bottom: 16px; transform: none; }
  .lightbox__nav:hover { transform: scale(1.06); }
  .lightbox__nav--prev { left: calc(50% - 54px); }
  .lightbox__nav--next { right: calc(50% - 54px); }
}