/* Minimal reset */
*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: system-ui, -apple-system, "Segoe UI", Roboto, Ubuntu, "Helvetica Neue", sans-serif;
  font-size: 1rem;
  line-height: 1.55;
  color: var(--color-text);
  background: var(--color-bg);
}

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

h1, h2, h3, p {
  margin: 0 0 0.75rem;
}

ul, ol {
  margin: 0;
  padding: 0;
  list-style: none;
}

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

a:hover {
  text-decoration: underline;
}

:root {
  --color-bg: #f8fafc;
  --color-bg-alt: #e2e8f0;
  --color-surface: #ffffff;
  --color-text: #0f172a;
  --color-muted: #64748b;
  --color-primary: #0284c7;
  --color-primary-hover: #0369a1;
  --color-accent: #0ea5e9;
  --color-error: #b91c1c;
  --color-success: #15803d;
  --radius: 12px;
  --shadow: 0 10px 40px rgba(15, 23, 42, 0.08);
  --container: 1100px;
}

.container {
  width: 100%;
  max-width: var(--container);
  margin: 0 auto;
  padding: 0 1.25rem;
}

/* Header */
.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(248, 250, 252, 0.92);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--color-bg-alt);
}

.header-inner {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  min-height: 4rem;
  padding-top: 0.75rem;
  padding-bottom: 0.75rem;
}

.logo {
  display: flex;
  align-items: center;
  gap: 0.65rem;
  color: var(--color-text);
  font-weight: 700;
  font-size: 1.25rem;
  text-decoration: none;
}

.logo:hover {
  text-decoration: none;
  color: var(--color-primary);
}

.logo__text {
  letter-spacing: -0.02em;
}

.nav-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 2.75rem;
  height: 2.75rem;
  padding: 0;
  border: 0;
  background: transparent;
  cursor: pointer;
  border-radius: 8px;
}

.nav-toggle:hover,
.nav-toggle:focus-visible {
  background: var(--color-bg-alt);
  outline: none;
}

.nav-toggle__bar {
  display: block;
  width: 1.35rem;
  height: 2px;
  margin: 0 auto;
  background: var(--color-text);
  border-radius: 1px;
  transition: transform 0.2s, opacity 0.2s;
}

.site-nav__list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.5rem 1.25rem;
}

.site-nav__list a {
  color: var(--color-text);
  font-weight: 500;
  padding: 0.35rem 0;
}

.site-nav__list a:hover {
  color: var(--color-primary);
}

/* Hero */
.hero {
  padding: 3rem 0 4rem;
  background: linear-gradient(135deg, #0f172a 0%, #0c4a6e 55%, #0369a1 100%);
  color: #f8fafc;
}

.hero__inner {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: flex-start;
}

.hero__content {
  flex: 1 1 320px;
  max-width: 36rem;
}

.hero h1 {
  font-size: clamp(1.75rem, 4vw, 2.5rem);
  line-height: 1.2;
  margin-bottom: 1rem;
}

.hero__lead {
  font-size: 1.1rem;
  opacity: 0.92;
  margin-bottom: 1.5rem;
  color: #e2e8f0;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.75rem 1.5rem;
  font-size: 1rem;
  font-weight: 600;
  border-radius: 10px;
  border: 2px solid transparent;
  cursor: pointer;
  text-decoration: none;
  transition: background 0.2s, color 0.2s, border-color 0.2s;
}

.btn:hover {
  text-decoration: none;
}

.btn--primary {
  background: var(--color-accent);
  color: #0f172a;
  border-color: var(--color-accent);
}

.btn--primary:hover {
  background: #7dd3fc;
  border-color: #7dd3fc;
}

.btn--primary:focus-visible {
  outline: 2px solid #f8fafc;
  outline-offset: 2px;
}

.btn--submit:disabled {
  opacity: 0.65;
  cursor: not-allowed;
}

/* Sections */
.section {
  padding: 3.5rem 0;
}

.section--alt {
  background: var(--color-bg-alt);
}

.section--order {
  background: var(--color-surface);
  box-shadow: inset 0 1px 0 var(--color-bg-alt);
}

.section__title {
  font-size: clamp(1.5rem, 3vw, 2rem);
  margin-bottom: 0.75rem;
  text-align: center;
}

.section__intro {
  text-align: center;
  color: var(--color-muted);
  max-width: 36rem;
  margin: 0 auto 2rem;
}

/* Cards — flex grids */
.cards {
  display: flex;
  flex-wrap: wrap;
  gap: 1.25rem;
  justify-content: center;
}

.card {
  background: var(--color-surface);
  border-radius: var(--radius);
  padding: 1.5rem;
  box-shadow: var(--shadow);
  flex: 1 1 min(260px, 100%);
  max-width: 100%;
}

.section--alt .card {
  background: var(--color-surface);
}

.card--feature .card__title,
.card--catalog .card__title {
  color: var(--color-primary);
  font-size: 1.15rem;
}

.cards--features .card {
  flex: 1 1 min(220px, 100%);
}

.cards--catalog .card {
  flex: 1 1 min(240px, 100%);
}

.cards--reviews {
  align-items: stretch;
}

.card--review {
  flex: 1 1 min(280px, 100%);
}

.card--review p {
  font-style: italic;
  margin-bottom: 1rem;
}

.card--review footer {
  font-size: 0.9rem;
  color: var(--color-muted);
  margin: 0;
}

/* Steps */
.steps {
  display: flex;
  flex-wrap: wrap;
  gap: 1.5rem;
  justify-content: center;
  max-width: 900px;
  margin: 0 auto;
}

.steps__item {
  display: flex;
  flex: 1 1 min(240px, 100%);
  gap: 1rem;
  align-items: flex-start;
  background: var(--color-surface);
  padding: 1.25rem 1.5rem;
  border-radius: var(--radius);
  box-shadow: var(--shadow);
}

.steps__num {
  flex-shrink: 0;
  width: 2.5rem;
  height: 2.5rem;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--color-primary);
  color: #fff;
  font-weight: 700;
  border-radius: 50%;
  font-size: 1.1rem;
}

.steps__heading {
  font-size: 1.1rem;
  margin-bottom: 0.35rem;
}

.steps__item p {
  margin: 0;
  color: var(--color-muted);
  font-size: 0.95rem;
}

/* Form */
.form-status {
  max-width: 40rem;
  margin: 0 auto 1.25rem;
  padding: 0.85rem 1rem;
  border-radius: var(--radius);
  font-weight: 500;
}

.form-status--ok {
  background: #dcfce7;
  color: var(--color-success);
  border: 1px solid #86efac;
}

.form-status--err {
  background: #fee2e2;
  color: var(--color-error);
  border: 1px solid #fca5a5;
}

.order-form {
  max-width: 40rem;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 1.25rem;
}

.form-row {
  display: flex;
  flex-wrap: wrap;
  gap: 1.25rem;
}

.form-row .field {
  flex: 1 1 min(220px, 100%);
}

.field {
  display: flex;
  flex-direction: column;
  gap: 0.35rem;
}

.field label {
  font-weight: 600;
  font-size: 0.95rem;
}

.req {
  color: var(--color-error);
}

.field input,
.field select,
.field textarea {
  font: inherit;
  padding: 0.65rem 0.85rem;
  border: 1px solid var(--color-bg-alt);
  border-radius: 8px;
  background: var(--color-bg);
  color: var(--color-text);
}

.field input:focus,
.field select:focus,
.field textarea:focus {
  outline: 2px solid var(--color-accent);
  outline-offset: 1px;
  border-color: var(--color-accent);
}

.field input.field--invalid,
.field select.field--invalid,
.field textarea.field--invalid {
  border-color: var(--color-error);
}

.field__hint {
  font-size: 0.8rem;
  color: var(--color-muted);
}

.field__error {
  min-height: 1.25rem;
  font-size: 0.85rem;
  color: var(--color-error);
}

.field--checkbox {
  flex-direction: row;
  flex-wrap: wrap;
  align-items: flex-start;
  gap: 0.5rem 0.75rem;
}

.field--checkbox input {
  width: 1.15rem;
  height: 1.15rem;
  margin-top: 0.2rem;
  flex-shrink: 0;
}

.field--checkbox label {
  font-weight: 500;
  flex: 1 1 200px;
}

.field--checkbox .field__error {
  flex: 1 1 100%;
  margin-left: 0;
}

/* Footer */
.site-footer {
  background: #0f172a;
  color: #cbd5e1;
  padding: 2.5rem 0 2rem;
}

.footer-inner {
  display: flex;
  flex-wrap: wrap;
  gap: 1.5rem 2rem;
  align-items: flex-start;
  justify-content: space-between;
}

.footer-brand {
  flex: 1 1 200px;
}

.footer-brand strong {
  color: #f8fafc;
  font-size: 1.1rem;
}

.footer-brand p {
  margin: 0.35rem 0 0;
  font-size: 0.9rem;
}

.footer-contacts {
  flex: 1 1 180px;
}

.footer-contacts p {
  margin: 0 0 0.35rem;
}

.footer-contacts a {
  color: #7dd3fc;
}

.footer-nav {
  flex: 1 1 200px;
}

.footer-nav__list {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem 1rem;
}

.footer-nav a {
  color: #e2e8f0;
}

.footer-copy {
  flex: 1 1 100%;
  margin: 0;
  padding-top: 1rem;
  border-top: 1px solid #334155;
  font-size: 0.85rem;
  color: #94a3b8;
}

/* Mobile nav */
@media (max-width: 768px) {
  .nav-toggle {
    display: flex;
  }

  .site-nav {
    flex: 1 1 100%;
    order: 3;
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.3s ease;
  }

  .site-nav.is-open {
    max-height: 320px;
  }

  .site-nav__list {
    flex-direction: column;
    align-items: stretch;
    padding: 0.5rem 0 1rem;
    gap: 0;
  }

  .site-nav__list a {
    display: block;
    padding: 0.75rem 0;
    border-bottom: 1px solid var(--color-bg-alt);
  }

  .site-header.is-nav-open .nav-toggle__bar:nth-child(1) {
    transform: translateY(7px) rotate(45deg);
  }

  .site-header.is-nav-open .nav-toggle__bar:nth-child(2) {
    opacity: 0;
  }

  .site-header.is-nav-open .nav-toggle__bar:nth-child(3) {
    transform: translateY(-7px) rotate(-45deg);
  }

  .hero {
    padding: 2.25rem 0 3rem;
  }

  .section {
    padding: 2.5rem 0;
  }
}