/* ============================================
   Sales2China — Russian Site
   Design system: Trust & Authority
   Palette: Navy + Vermilion | Type: Playfair + Inter
   ============================================ */

/* ── Design Tokens ── */
:root {
  --color-abyss: #0F172A;
  --color-abyss-light: #1E293B;
  --color-abyss-surface: #1A2740;
  --color-bg: #F8FAFC;
  --color-bg-alt: #F1F5F9;
  --color-surface: #FFFFFF;
  --color-accent: #C62828;
  --color-accent-hover: #AD2222;
  --color-accent-glow: rgba(198, 40, 40, 0.12);
  --color-text: #1E293B;
  --color-body: #475569;
  --color-muted: #64748B;
  --color-border: #E2E8F0;
  --color-border-light: #F1F5F9;

  --font-display: 'Playfair Display', 'Georgia', serif;
  --font-body: 'Inter', system-ui, -apple-system, sans-serif;

  --container-max: 72rem;
  --header-height: 4rem;
  --section-gap: clamp(4.5rem, 8vw, 7rem);

  --radius-sm: 4px;
  --radius-md: 6px;

  --shadow-sm: 0 1px 2px rgba(0,0,0,0.04);
  --shadow-md: 0 4px 12px rgba(0,0,0,0.06);
  --shadow-lg: 0 8px 24px rgba(0,0,0,0.08);

  --transition-fast: 0.15s ease;
  --transition-base: 0.25s ease;
  --transition-slow: 0.4s ease;
}

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

html {
  -webkit-text-size-adjust: 100%;
  text-size-adjust: 100%;
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-body);
  font-size: 1.0625rem;
  font-weight: 400;
  line-height: 1.72;
  color: var(--color-body);
  background: var(--color-bg);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

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

a { color: inherit; text-decoration-thickness: 1px; text-underline-offset: 3px; }
ul, ol { list-style: none; }

::selection { background: var(--color-accent); color: #fff; }

:focus-visible {
  outline: 2px solid var(--color-accent);
  outline-offset: 2px;
}

/* ── Skip Link ── */
.skip-link {
  position: fixed; top: 3px; left: 1rem; z-index: 1010;
  padding: 0.5rem 1rem;
  background: var(--color-accent); color: #fff;
  font-weight: 600; font-size: 0.875rem;
  border-radius: var(--radius-sm); text-decoration: none;
  transform: translateY(-120%);
  transition: transform var(--transition-fast);
}
.skip-link:focus { transform: translateY(0); }

/* ── Top Rule ── */
.top-rule {
  position: fixed; top: 0; left: 0; right: 0; height: 1.5px;
  background: var(--color-accent); z-index: 999; pointer-events: none;
}

/* ── Container ── */
.container {
  width: 100%; max-width: var(--container-max);
  margin-inline: auto;
  padding-inline: clamp(1rem, 5vw, 2.5rem);
}

/* ── Eyebrow ── */
.eyebrow {
  display: inline-block;
  font-family: var(--font-body);
  font-weight: 600; font-size: 0.75rem;
  text-transform: uppercase; letter-spacing: 0.12em;
  color: var(--color-accent);
  margin-block-end: 0.5rem;
}
.eyebrow-center { display: block; text-align: center; }
.eyebrow-light { color: rgba(255,255,255,0.55); }

/* ── Buttons ── */
.btn {
  display: inline-flex; align-items: center; justify-content: center;
  gap: 0.5em; padding: 0.7em 1.75em;
  font-family: var(--font-body); font-weight: 600;
  font-size: 0.9375rem; line-height: 1.2;
  border: none; border-radius: var(--radius-sm);
  cursor: pointer; text-decoration: none; white-space: nowrap;
  transition: background var(--transition-fast), color var(--transition-fast), box-shadow var(--transition-fast);
}
.btn:active { transform: scale(0.985); }

.btn-accent {
  background: var(--color-accent); color: #fff;
}
.btn-accent:hover {
  background: var(--color-accent-hover);
  box-shadow: 0 2px 8px var(--color-accent-glow);
}
.btn-accent:focus-visible { outline-offset: 3px; }

.btn-outline-light {
  background: transparent; color: rgba(255,255,255,0.85);
  box-shadow: inset 0 0 0 1.5px rgba(255,255,255,0.25);
}
.btn-outline-light:hover {
  background: rgba(255,255,255,0.06); color: #fff;
  box-shadow: inset 0 0 0 1.5px rgba(255,255,255,0.5);
}

.btn-xl { padding: 1em 2.5em; font-size: 1.0625rem; }
.btn-sm { padding: 0.5em 1.25em; font-size: 0.8125rem; }
.btn-nav { padding: 0.5em 1.25em; font-size: 0.875rem; }
.btn-sub {
  font-weight: 400; font-size: 0.8em; opacity: 0.7;
  border-left: 1px solid rgba(255,255,255,0.3);
  padding-left: 0.6em; margin-left: 0.3em;
}

/* ── Header ── */
.site-header {
  position: fixed; top: 1.5px; left: 0; right: 0; z-index: 900;
  height: var(--header-height);
  display: flex; align-items: center;
  border-bottom: 1.5px solid transparent;
  transition: background var(--transition-base), border-color var(--transition-base);
}
.no-js .site-header {
  background: var(--color-abyss);
  border-bottom-color: var(--color-accent);
}
.site-header.header-scrolled {
  background: rgba(255,255,255,0.88);
  -webkit-backdrop-filter: blur(16px); backdrop-filter: blur(16px);
  border-bottom-color: var(--color-border);
  box-shadow: var(--shadow-sm);
}

.header-inner {
  display: flex; align-items: center; justify-content: space-between;
  width: 100%; max-width: var(--container-max);
  margin-inline: auto;
  padding-inline: clamp(1rem, 5vw, 2.5rem);
}

.logo {
  font-family: var(--font-display); font-weight: 700;
  font-size: 1.125rem; letter-spacing: 0.02em;
  color: #fff; text-decoration: none;
  display: flex; align-items: baseline; gap: 0.35em;
  transition: color var(--transition-base);
}
.header-scrolled .logo { color: var(--color-text); }
.no-js .logo { color: #fff; }

.logo-name { font-weight: 700; }
.logo-sep { color: var(--color-accent); font-weight: 500; font-size: 0.9em; }
.logo-domain { font-weight: 500; color: rgba(255,255,255,0.65); }
.header-scrolled .logo-domain { color: var(--color-muted); }

.header-nav { display: flex; align-items: center; gap: 0.25rem; }

.nav-link {
  padding: 0.45rem 0.8rem;
  font-family: var(--font-body); font-weight: 500;
  font-size: 0.875rem; color: rgba(255,255,255,0.75);
  text-decoration: none;
  transition: color var(--transition-fast);
}
.nav-link:hover { color: #fff; }
.header-scrolled .nav-link { color: var(--color-body); }
.header-scrolled .nav-link:hover { color: var(--color-text); }
.no-js .nav-link { color: rgba(255,255,255,0.75); }

/* ── Sections ── */
.section { padding-block: var(--section-gap); }
.section-alt { background: var(--color-bg-alt); }
.section-dark { background: var(--color-abyss); color: rgba(255,255,255,0.75); }
.section-dark-alt {
  background: var(--color-abyss);
  color: rgba(255,255,255,0.75);
  border-top: 1px solid rgba(255,255,255,0.06);
}

.section-title {
  font-family: var(--font-display); font-weight: 600;
  font-size: clamp(1.6rem, 3.5vw, 2.35rem);
  line-height: 1.18; letter-spacing: -0.01em;
  color: var(--color-text); margin-block-end: 1.25rem;
}
.section-title-light { color: #fff; }
.section-title-center { text-align: center; }

/* ── Reveal ── */
.reveal {
  opacity: 0; transform: translateY(24px);
  transition: opacity 0.7s ease, transform 0.7s ease;
}
.reveal.revealed { opacity: 1; transform: translateY(0); }

/* ── Hero ── */
.hero {
  position: relative;
  min-height: 100vh; min-height: 100dvh;
  display: flex; align-items: center; justify-content: center;
  background: var(--color-abyss);
  text-align: center; overflow: hidden;
  border-bottom: 1.5px solid var(--color-accent);
  padding-block: var(--header-height) 4rem;
}

.hero-bg {
  position: absolute; inset: 0;
  background:
    radial-gradient(ellipse 80% 50% at 50% 40%, rgba(198,40,40,0.06) 0%, transparent 70%),
    radial-gradient(ellipse 60% 40% at 25% 70%, rgba(30,41,59,0.4) 0%, transparent 60%),
    var(--color-abyss);
}

.hero-inner {
  position: relative; z-index: 1;
  display: flex; flex-direction: column; align-items: center;
  gap: 1.5rem; padding-inline: 1rem;
}

.hero-title {
  font-family: var(--font-display); font-weight: 700;
  font-size: clamp(2.25rem, 6vw, 5rem);
  line-height: 1.08; letter-spacing: -0.02em;
  color: #fff; max-width: 14ch;
}

.hero-lead {
  font-family: var(--font-body); font-weight: 400;
  font-size: clamp(1rem, 2vw, 1.25rem);
  color: rgba(255,255,255,0.6);
  max-width: 36ch;
}

/* ── About ── */
.about-grid {
  display: grid; grid-template-columns: 5fr 7fr;
  gap: clamp(2.5rem, 7vw, 5rem); align-items: start;
}

.about-figure {
  margin: 0; position: relative;
  aspect-ratio: 3 / 4; overflow: hidden;
  background: var(--color-border-light);
}
.about-figure img { width: 100%; height: 100%; object-fit: cover; }
.about-caption {
  position: absolute; bottom: 1rem; left: 1rem;
  font-family: var(--font-body); font-weight: 500;
  font-size: 0.75rem; color: #fff; letter-spacing: 0.06em;
  text-transform: uppercase;
  background: rgba(15,23,42,0.7);
  padding: 0.35em 0.75em; border-radius: var(--radius-sm);
}

.about-body { display: flex; flex-direction: column; gap: 1rem; padding-block-start: 0.5rem; }

.about-role {
  font-family: var(--font-display); font-style: italic; font-weight: 500;
  font-size: 1.125rem; color: var(--color-accent);
  margin-block-start: -0.75rem; margin-block-end: 0.25rem;
}

.about-text p { font-size: 1.0625rem; max-width: 48ch; }

.credentials {
  display: grid; grid-template-columns: repeat(3, 1fr);
  gap: 1.25rem;
  margin-block-start: 1rem;
}
.credentials li {
  display: flex; flex-direction: column; gap: 0.2rem;
}
.credentials li strong {
  font-weight: 600; font-size: 0.75rem;
  color: var(--color-accent); letter-spacing: 0.08em;
  text-transform: uppercase;
}
.credentials li span {
  font-size: 0.9375rem; color: var(--color-body);
}

/* ── Trust Bar ── */
.section-trust {
  padding-block: 3rem;
  background: var(--color-abyss-light);
  border-top: 1px solid rgba(255,255,255,0.06);
  border-bottom: 1px solid rgba(255,255,255,0.06);
}

.trust-bar {
  display: flex; align-items: center; justify-content: center;
  gap: 0; flex-wrap: wrap;
}

.trust-stat {
  display: flex; flex-direction: column; align-items: center;
  text-align: center; padding: 1rem 2rem;
  min-width: 140px; gap: 0.25rem;
}

.trust-figure {
  font-family: var(--font-display); font-weight: 700;
  font-size: clamp(2.25rem, 4vw, 3.25rem);
  line-height: 1.1; color: #fff;
}
.trust-unit {
  font-family: var(--font-display); font-weight: 500;
  font-size: 0.55em; color: var(--color-accent);
  display: inline;
}
.trust-percent { font-size: 0.6em; color: var(--color-accent); }
.trust-label {
  font-size: 0.8125rem; color: rgba(255,255,255,0.55);
  line-height: 1.4;
}

.trust-divider {
  width: 1px; height: 4rem;
  background: rgba(255,255,255,0.1);
  flex-shrink: 0;
}

/* ── Expertise ── */
.expertise-grid {
  display: grid; grid-template-columns: repeat(3, 1fr);
  gap: clamp(1.5rem, 3vw, 2.5rem);
}

.expertise-card {
  padding: 2rem 1.5rem;
  border: 1px solid var(--color-border-light);
  background: var(--color-surface);
  text-align: center;
  transition: border-color var(--transition-base), box-shadow var(--transition-base);
}
.expertise-card:hover {
  border-color: var(--color-accent);
  box-shadow: var(--shadow-md);
}

.expertise-marker {
  display: block; width: 8px; height: 8px;
  background: var(--color-accent);
  margin-block-end: 1.25rem;
  margin-inline: auto;
}

.expertise-title {
  font-family: var(--font-display); font-weight: 600;
  font-size: 1.125rem; color: var(--color-text);
  margin-block-end: 0.6rem;
}
.expertise-card p { font-size: 0.9375rem; color: var(--color-body); }

/* ── Services ── */
.services-grid {
  display: grid; grid-template-columns: repeat(2, 1fr);
  gap: clamp(1.25rem, 3vw, 2rem);
  margin-block-start: 2.5rem;
}

.service-card {
  padding: 2.5rem 2rem;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  text-align: center;
  transition: border-color var(--transition-base), box-shadow var(--transition-base);
  position: relative; overflow: hidden;
}
.service-card::before {
  content: ''; position: absolute; top: 0; left: 0; right: 0;
  height: 2px; background: var(--color-accent);
  transform: scaleX(0); transform-origin: left;
  transition: transform var(--transition-base);
}
.service-card:hover {
  border-color: var(--color-accent);
  box-shadow: var(--shadow-md);
}
.service-card:hover::before { transform: scaleX(1); }

.service-num {
  font-family: var(--font-display); font-weight: 700;
  font-size: 2.5rem; line-height: 1;
  color: var(--color-border);
  margin-block-end: 0.5rem;
  transition: color var(--transition-base);
}
.service-card:hover .service-num { color: var(--color-accent); }

.service-title {
  font-family: var(--font-display); font-weight: 600;
  font-size: 1.25rem; color: var(--color-text);
  margin-block-end: 0.65rem;
}
.service-card p { font-size: 0.9375rem; color: var(--color-body); }

/* ── Experience ── */
.experience-grid {
  display: grid; grid-template-columns: 1fr 1fr;
  gap: clamp(2.5rem, 6vw, 4rem); align-items: center;
}

.experience-body { display: flex; flex-direction: column; gap: 1.25rem; }

.experience-lead {
  font-size: 1.0625rem; line-height: 1.7;
  max-width: 40ch;
}

.experience-figure {
  margin: 0; aspect-ratio: 3 / 2;
  overflow: hidden; background: rgba(255,255,255,0.05);
  position: relative;
}
.experience-figure img { width: 100%; height: 100%; object-fit: cover; }

.experience-caption {
  position: absolute; bottom: 1rem; left: 1rem; right: 1rem;
  font-family: var(--font-display); font-style: italic; font-weight: 500;
  font-size: 0.9375rem; color: #fff;
  background: rgba(15,23,42,0.65);
  padding: 0.5rem 1rem; border-radius: var(--radius-sm);
}

/* ── Cases ── */
.cases-grid {
  display: grid; grid-template-columns: repeat(2, 1fr);
  gap: clamp(1.5rem, 3vw, 2.5rem);
  margin-block-start: 2.5rem;
}

.case-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  overflow: hidden;
  transition: border-color var(--transition-base), box-shadow var(--transition-base);
}
.case-card:hover {
  border-color: var(--color-accent);
  box-shadow: var(--shadow-md);
}

.case-img-wrap {
  aspect-ratio: 3 / 2; overflow: hidden;
  background: var(--color-border-light);
}
.case-img-wrap img {
  width: 100%; height: 100%; object-fit: cover;
  transition: transform var(--transition-slow);
}
.case-card:hover .case-img-wrap img { transform: scale(1.04); }

.case-body { padding: 1.75rem; text-align: center; }

.case-badge {
  display: inline-block;
  font-family: var(--font-body); font-weight: 600;
  font-size: 0.6875rem; text-transform: uppercase; letter-spacing: 0.1em;
  color: var(--color-accent);
  background: var(--color-accent-glow);
  padding: 0.3em 0.75em; border-radius: var(--radius-sm);
  margin-block-end: 0.75rem;
}

.case-title {
  font-family: var(--font-display); font-weight: 600;
  font-size: 1.25rem; color: var(--color-text);
  margin-block-end: 0.35rem;
}

.case-metric {
  font-weight: 500; font-size: 0.9375rem;
  color: var(--color-text); margin-block-end: 0.6rem;
}
.case-metric strong { color: var(--color-accent); font-weight: 600; }

.case-body > p { font-size: 0.9375rem; color: var(--color-body); }

/* ── Video ── */
.testimonial-wrap { max-width: 56rem; margin-inline: auto; }
.video-player {
  margin-block-start: 2.5rem;
  background: var(--color-abyss);
  border: 1px solid var(--color-border);
}
.video-player video { width: 100%; display: block; }

/* ── Partners ── */
.partners-grid {
  display: flex; flex-wrap: wrap; align-items: center; justify-content: center;
  gap: clamp(2rem, 5vw, 4rem);
  margin-block-start: 2rem;
}

.partner-link {
  display: flex; align-items: center; justify-content: center;
  opacity: 0.55; filter: grayscale(1);
  transition: opacity var(--transition-base), filter var(--transition-base);
}
.partner-link:hover { opacity: 1; filter: grayscale(0); }
.partner-link img { max-width: 180px; max-height: 56px; object-fit: contain; }

/* ── Books ── */
.books-scroll {
  display: flex; gap: 1.5rem;
  overflow-x: auto; scroll-snap-type: x mandatory;
  -webkit-overflow-scrolling: touch;
  padding-block: 0.5rem; margin-block-start: 2.5rem;
  margin-inline: calc(-1 * clamp(1rem, 5vw, 2.5rem));
  padding-inline: clamp(1rem, 5vw, 2.5rem);
}

.books-scroll::-webkit-scrollbar { height: 3px; }
.books-scroll::-webkit-scrollbar-track { background: rgba(255,255,255,0.04); }
.books-scroll::-webkit-scrollbar-thumb { background: var(--color-accent); border-radius: 2px; }

.book-card {
  flex: 0 0 270px; scroll-snap-align: start;
  display: flex; flex-direction: column;
  background: var(--color-abyss-surface);
  border: 1px solid rgba(255,255,255,0.06);
  overflow: hidden;
  transition: border-color var(--transition-base);
}
.book-card:hover { border-color: rgba(198,40,40,0.4); }

.book-cover {
  aspect-ratio: 3 / 4.2;
  background: rgba(255,255,255,0.05);
  overflow: hidden; display: flex; align-items: center; justify-content: center;
}
.book-cover img { width: 100%; height: 100%; object-fit: cover; }

.book-cover-plain {
  display: flex; align-items: center; justify-content: center;
  background: var(--color-abyss-light);
}
.book-cover-label {
  font-family: var(--font-display); font-weight: 600;
  font-size: 1rem; line-height: 1.4; text-align: center;
  color: rgba(255,255,255,0.55); padding: 1.5rem;
}

.book-body { padding: 1.5rem; display: flex; flex-direction: column; gap: 0.75rem; flex: 1; text-align: center; align-items: center; }

.book-title {
  font-family: var(--font-display); font-weight: 600;
  font-size: 1.0625rem; color: #fff;
}
.book-desc { font-size: 0.8125rem; line-height: 1.6; flex: 1; }

/* ── Course ── */
.course-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  padding: clamp(2rem, 5vw, 3rem);
  max-width: 48rem; margin-inline: auto;
  text-align: center;
  transition: border-color var(--transition-base), box-shadow var(--transition-base);
}
.course-card:hover { border-color: var(--color-accent); box-shadow: var(--shadow-md); }

.course-lead {
  font-family: var(--font-display); font-style: italic; font-weight: 500;
  font-size: 1.0625rem; color: var(--color-text);
  margin-block-end: 1.25rem;
}
.course-body { font-size: 0.9375rem; color: var(--color-body); margin-block-end: 1.75rem; }

/* ── Contact ── */
.contact-inner {
  max-width: 40rem; margin-inline: auto;
  text-align: center; display: flex; flex-direction: column; align-items: center;
}
.contact-lead {
  font-size: 1.125rem; max-width: 40ch;
  margin-block-end: 2.5rem;
}
.contact-links { display: flex; flex-wrap: wrap; gap: 1rem; justify-content: center; }

/* ── Footer ── */
.site-footer {
  background: #070D17; color: rgba(255,255,255,0.45);
  padding-block: 3rem 2rem; font-size: 0.875rem;
}

.footer-grid {
  display: grid; grid-template-columns: 1fr auto;
  gap: 1.5rem 4rem; align-items: start;
}

.footer-brand { display: flex; flex-direction: column; gap: 0.35rem; }
.footer-name {
  font-family: var(--font-display); font-weight: 700;
  font-size: 0.9375rem; color: rgba(255,255,255,0.6);
}
.footer-legal { font-size: 0.8125rem; line-height: 1.6; color: rgba(255,255,255,0.3); }

.footer-links { display: flex; gap: 1.5rem; align-items: center; }
.footer-link {
  font-weight: 500; color: rgba(255,255,255,0.45); text-decoration: none;
  transition: color var(--transition-fast);
}
.footer-link:hover { color: var(--color-accent); }

.footer-copy {
  grid-column: 1 / -1;
  border-block-start: 1px solid rgba(255,255,255,0.06);
  padding-block-start: 1.5rem;
  color: rgba(255,255,255,0.25);
}

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

@media (max-width: 1024px) {
  .about-grid { grid-template-columns: 1fr; gap: 2rem; }
  .about-figure { max-width: 28rem; }
}

@media (max-width: 768px) {
  :root { --header-height: 3.5rem; }

  .nav-link { display: none; }
  .header-nav .btn-nav { font-size: 0.8125rem; padding: 0.45em 1.1em; }

  .hero { min-height: 90vh; min-height: 90dvh; }
  .hero-title { font-size: clamp(1.75rem, 8vw, 3rem); }

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

  .expertise-grid { grid-template-columns: 1fr; }
  .services-grid { grid-template-columns: 1fr; }
  .cases-grid { grid-template-columns: 1fr; }
  .experience-grid { grid-template-columns: 1fr; gap: 2rem; }
  .experience-figure { order: -1; }

  .trust-bar { gap: 1rem; }
  .trust-stat { padding: 0.75rem 1.25rem; min-width: 120px; }
  .trust-divider { display: none; }

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

  .book-card { flex: 0 0 230px; }
}

@media (max-width: 480px) {
  .logo { font-size: 1rem; }
  .hero-lead { font-size: 0.9375rem; }
  .about-caption { font-size: 0.6875rem; }

  .trust-stat { min-width: 100px; padding: 0.5rem 1rem; }
  .trust-figure { font-size: 1.75rem; }

  .service-card { padding: 1.5rem; }
  .case-body { padding: 1.25rem; }

  .contact-links { flex-direction: column; width: 100%; }
  .contact-links .btn { width: 100%; justify-content: center; }

  .partners-grid { gap: 1.5rem; flex-direction: column; }
  .partner-link img { max-width: 160px; }

  .section-title { font-size: clamp(1.35rem, 7vw, 1.75rem); }
}

/* ── Reduced Motion ── */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .reveal { opacity: 1; transform: none; transition: none; }
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}