/* =========================================================
   Alexander Kucherov — Personal Website
   Design system: premium, minimalist, executive.
   ========================================================= */

:root {
  /* Colour palette */
  --color-bg: #FBFBF9;
  --color-bg-alt: #F2F1EC;
  --color-surface: #FFFFFF;
  --color-ink: #14172A;
  --color-ink-soft: #4A4F63;
  --color-ink-faint: #7A7F94;
  --color-accent: #2A46C7;
  --color-accent-ink: #1B2E8C;
  --color-accent-soft: #E7EBFA;
  --color-line: #E3E1D9;
  --color-line-soft: #ECEAE2;

  /* Typography */
  --font-display: 'Fraunces', Georgia, 'Times New Roman', serif;
  --font-body: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;

  /* Layout */
  --container-width: 1160px;
  --radius-sm: 6px;
  --radius-md: 12px;
  --radius-lg: 20px;
  --shadow-card: 0 1px 2px rgba(20, 23, 42, 0.04), 0 10px 30px -14px rgba(20, 23, 42, 0.12);
  --shadow-card-hover: 0 4px 10px rgba(20, 23, 42, 0.06), 0 20px 40px -16px rgba(20, 23, 42, 0.16);
  --transition: 220ms cubic-bezier(0.4, 0, 0.2, 1);
}

/* ---------- Reset ---------- */
*, *::before, *::after { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  font-family: var(--font-body);
  color: var(--color-ink);
  background: var(--color-bg);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}
img { max-width: 100%; display: block; }
a { color: inherit; text-decoration: none; }
ul, ol { list-style: none; margin: 0; padding: 0; }
h1, h2, h3, h4, p { margin: 0; }
button { font: inherit; cursor: pointer; }
input, select, textarea { font: inherit; }

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  * { animation-duration: 0.01ms !important; animation-iteration-count: 1 !important; transition-duration: 0.01ms !important; }
}

.visually-hidden {
  position: absolute;
  width: 1px; height: 1px;
  padding: 0; margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

.skip-link {
  position: absolute;
  top: -48px;
  left: 12px;
  background: var(--color-ink);
  color: #fff;
  padding: 12px 18px;
  border-radius: var(--radius-sm);
  z-index: 1000;
  transition: top var(--transition);
}
.skip-link:focus { top: 12px; }

:focus-visible {
  outline: 2px solid var(--color-accent);
  outline-offset: 3px;
}

.container {
  width: 100%;
  max-width: var(--container-width);
  margin-inline: auto;
  padding-inline: 24px;
}

/* ---------- Typography helpers ---------- */
.eyebrow {
  font-size: 0.8rem;
  font-weight: 600;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--color-accent);
  margin-bottom: 12px;
}

h1, h2, h3 { font-family: var(--font-display); font-weight: 600; color: var(--color-ink); line-height: 1.15; }
h1 { font-size: clamp(2.4rem, 4.5vw + 1rem, 4rem); letter-spacing: -0.01em; }
h2 { font-size: clamp(1.9rem, 2.6vw + 1rem, 2.6rem); letter-spacing: -0.01em; }
h3 { font-size: 1.25rem; }

.section-lede {
  color: var(--color-ink-soft);
  font-size: 1.05rem;
  max-width: 620px;
  margin-top: 14px;
}

/* ---------- Buttons ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 14px 28px;
  border-radius: var(--radius-sm);
  font-weight: 600;
  font-size: 0.95rem;
  border: 1px solid transparent;
  transition: transform var(--transition), background var(--transition), color var(--transition), border-color var(--transition), box-shadow var(--transition);
}
.btn-primary {
  background: var(--color-ink);
  color: #fff;
}
.btn-primary:hover { background: var(--color-accent-ink); transform: translateY(-1px); }
.btn-ghost {
  background: transparent;
  color: var(--color-ink);
  border-color: var(--color-line);
}
.btn-ghost:hover { border-color: var(--color-ink); transform: translateY(-1px); }
.btn-full { width: 100%; }

/* ---------- Header ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(251, 251, 249, 0.86);
  backdrop-filter: saturate(180%) blur(14px);
  border-bottom: 1px solid transparent;
  transition: border-color var(--transition), box-shadow var(--transition);
}
.site-header.is-scrolled {
  border-bottom-color: var(--color-line);
  box-shadow: 0 1px 0 rgba(20,23,42,0.02);
}
.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 76px;
}
.brand {
  font-family: var(--font-display);
  font-weight: 600;
  font-size: 1.15rem;
  letter-spacing: -0.01em;
}

.primary-nav ul {
  display: flex;
  align-items: center;
  gap: 32px;
}
.primary-nav a {
  font-size: 0.95rem;
  font-weight: 500;
  color: var(--color-ink-soft);
  transition: color var(--transition);
}
.primary-nav a:hover { color: var(--color-ink); }
.nav-cta {
  padding: 9px 18px;
  border-radius: var(--radius-sm);
  background: var(--color-ink);
  color: #fff !important;
}
.nav-cta:hover { background: var(--color-accent-ink); }

.nav-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 40px;
  height: 40px;
  background: transparent;
  border: none;
  padding: 0;
}
.nav-toggle-bar {
  width: 22px;
  height: 2px;
  background: var(--color-ink);
  transition: transform var(--transition), opacity var(--transition);
}
.nav-toggle[aria-expanded="true"] .nav-toggle-bar:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.nav-toggle[aria-expanded="true"] .nav-toggle-bar:nth-child(2) { opacity: 0; }
.nav-toggle[aria-expanded="true"] .nav-toggle-bar:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

/* ---------- Hero ---------- */
.hero {
  padding-block: clamp(64px, 10vw, 128px) clamp(56px, 8vw, 96px);
}
.hero-inner {
  display: grid;
  grid-template-columns: 1.15fr 0.85fr;
  gap: clamp(32px, 5vw, 72px);
  align-items: center;
}
.hero-subhead {
  font-size: 1.1rem;
  font-weight: 500;
  color: var(--color-accent-ink);
  margin-top: 20px;
}
.hero-statement {
  margin-top: 24px;
  font-size: 1.08rem;
  color: var(--color-ink-soft);
  max-width: 56ch;
}
.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 16px;
  margin-top: 36px;
}
.hero-contact {
  margin-top: 28px;
  font-size: 0.92rem;
  color: var(--color-ink-faint);
  display: flex;
  gap: 10px;
  flex-wrap: wrap;
}
.hero-contact a { color: var(--color-ink-soft); transition: color var(--transition); }
.hero-contact a:hover { color: var(--color-accent); }

.hero-portrait img {
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-card-hover);
  width: 100%;
  height: auto;
  aspect-ratio: 5 / 6;
  object-fit: cover;
}

/* ---------- Sections ---------- */
.section { padding-block: clamp(64px, 8vw, 108px); }
.section-alt { background: var(--color-bg-alt); }
.section-head { max-width: 700px; margin-bottom: clamp(36px, 5vw, 56px); }

/* ---------- About ---------- */
.about-grid {
  display: grid;
  grid-template-columns: 1.3fr 1fr;
  gap: clamp(32px, 5vw, 64px);
  align-items: start;
}
.about-copy p { color: var(--color-ink-soft); margin-bottom: 18px; font-size: 1.02rem; }
.about-copy p:last-child { margin-bottom: 0; }
.about-facts {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 12px 20px;
  padding: 28px;
  background: var(--color-surface);
  border: 1px solid var(--color-line);
  border-radius: var(--radius-md);
}
.about-facts li {
  font-size: 0.92rem;
  color: var(--color-ink-soft);
  padding-left: 18px;
  position: relative;
}
.about-facts li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 9px;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--color-accent);
}

/* ---------- Numbers ---------- */
.numbers-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1px;
  background: var(--color-line);
  border: 1px solid var(--color-line);
  border-radius: var(--radius-md);
  overflow: hidden;
}
.number-card {
  background: var(--color-surface);
  padding: 36px 28px;
  text-align: center;
}
.number-value {
  font-family: var(--font-display);
  font-size: clamp(2rem, 3vw, 2.6rem);
  font-weight: 600;
  color: var(--color-accent-ink);
}
.number-label {
  margin-top: 10px;
  font-size: 0.88rem;
  color: var(--color-ink-soft);
}
.numbers-footnote {
  text-align: center;
  margin-top: 28px;
  color: var(--color-ink-faint);
  font-size: 0.9rem;
}

/* ---------- Card grids ---------- */
.card-grid { display: grid; gap: 22px; }
.card-grid-3 { grid-template-columns: repeat(3, 1fr); }
.card-grid-2 { grid-template-columns: repeat(2, 1fr); }

.expertise-card, .case-card, .service-card {
  background: var(--color-surface);
  border: 1px solid var(--color-line);
  border-radius: var(--radius-md);
  padding: 30px;
  box-shadow: var(--shadow-card);
  transition: box-shadow var(--transition), transform var(--transition);
}
.expertise-card:hover, .case-card:hover, .service-card:hover {
  box-shadow: var(--shadow-card-hover);
  transform: translateY(-2px);
}
.expertise-card h3 { font-size: 1.1rem; margin-bottom: 10px; }
.expertise-card p { color: var(--color-ink-soft); font-size: 0.95rem; }

/* ---------- Services ---------- */
.service-card h3 { margin-bottom: 8px; }
.service-for { color: var(--color-ink-soft); font-size: 0.92rem; margin-bottom: 18px; }
.service-card ul { margin-bottom: 22px; }
.service-card li {
  font-size: 0.92rem;
  color: var(--color-ink-soft);
  padding: 7px 0 7px 20px;
  border-top: 1px solid var(--color-line-soft);
  position: relative;
}
.service-card li:first-child { border-top: none; }
.service-card li::before {
  content: "\2013";
  position: absolute;
  left: 0;
  color: var(--color-accent);
}
.service-card-wide { grid-column: 1 / -1; }
.service-list-inline { display: grid; grid-template-columns: repeat(2, 1fr); }
.service-link {
  display: inline-block;
  font-weight: 600;
  font-size: 0.92rem;
  color: var(--color-accent-ink);
  transition: color var(--transition);
}
.service-link:hover { color: var(--color-accent); }

/* ---------- How I Work ---------- */
.method-steps {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 28px 32px;
  counter-reset: step;
}
.method-step { position: relative; padding-top: 8px; border-top: 2px solid var(--color-line); }
.method-index {
  display: block;
  font-family: var(--font-display);
  font-size: 0.95rem;
  color: var(--color-accent);
  font-weight: 600;
  margin-bottom: 14px;
}
.method-step h3 { margin-bottom: 8px; }
.method-step p { color: var(--color-ink-soft); font-size: 0.95rem; }

/* ---------- Experience timeline ---------- */
.timeline { display: flex; flex-direction: column; gap: 40px; }
.timeline-item {
  display: grid;
  grid-template-columns: 220px 1fr;
  gap: 32px;
  padding-bottom: 40px;
  border-bottom: 1px solid var(--color-line);
}
.timeline-item:last-child { border-bottom: none; padding-bottom: 0; }
.timeline-dates {
  font-weight: 600;
  font-size: 0.92rem;
  color: var(--color-accent-ink);
  margin-bottom: 6px;
}
.timeline-company { color: var(--color-ink-faint); font-size: 0.9rem; }
.timeline-content h3 { margin-bottom: 12px; }
.timeline-content p { color: var(--color-ink-soft); font-size: 0.98rem; }
.timeline-impact {
  margin-top: 14px;
  font-size: 0.9rem;
  color: var(--color-accent-ink);
  font-weight: 500;
}
.timeline-item-condensed .timeline-content p { font-size: 0.95rem; }

/* ---------- Case studies ---------- */
.case-tag {
  font-size: 0.78rem;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--color-accent);
  margin-bottom: 12px;
}
.case-card h3 { margin-bottom: 14px; font-size: 1.15rem; }
.case-card p { color: var(--color-ink-soft); font-size: 0.92rem; margin-bottom: 12px; }
.case-card p:last-child { margin-bottom: 0; }
.case-card strong { color: var(--color-ink); }

/* ---------- Who I work with ---------- */
.audience-grid {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
}
.audience-grid li {
  padding: 12px 22px;
  background: var(--color-surface);
  border: 1px solid var(--color-line);
  border-radius: 999px;
  font-size: 0.92rem;
  font-weight: 500;
  color: var(--color-ink-soft);
}

/* ---------- Contact ---------- */
.contact-grid {
  display: grid;
  grid-template-columns: 0.85fr 1.15fr;
  gap: clamp(32px, 5vw, 72px);
  align-items: start;
}
.contact-intro p { color: var(--color-ink-soft); margin-top: 18px; max-width: 46ch; }
.contact-direct { margin-top: 28px !important; font-size: 0.98rem; line-height: 2; }
.contact-direct a { color: var(--color-accent-ink); font-weight: 500; }
.contact-direct a:hover { color: var(--color-accent); }

.contact-form {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 20px 20px;
  background: var(--color-surface);
  border: 1px solid var(--color-line);
  border-radius: var(--radius-md);
  padding: clamp(24px, 4vw, 36px);
  box-shadow: var(--shadow-card);
}
.form-row { display: flex; flex-direction: column; gap: 8px; }
.form-row-full { grid-column: 1 / -1; }
.form-row label { font-size: 0.88rem; font-weight: 600; color: var(--color-ink); }
.form-row input, .form-row select, .form-row textarea {
  padding: 12px 14px;
  border: 1px solid var(--color-line);
  border-radius: var(--radius-sm);
  background: var(--color-bg);
  color: var(--color-ink);
  transition: border-color var(--transition), box-shadow var(--transition);
}
.form-row input:focus, .form-row select:focus, .form-row textarea:focus {
  border-color: var(--color-accent);
  box-shadow: 0 0 0 3px var(--color-accent-soft);
  outline: none;
}
.form-row textarea { resize: vertical; min-height: 120px; }
.form-error {
  font-size: 0.82rem;
  color: #B4232C;
  min-height: 1em;
}
.form-row.has-error input,
.form-row.has-error textarea {
  border-color: #B4232C;
}
.form-status {
  margin-top: 14px;
  font-size: 0.9rem;
  color: var(--color-ink-soft);
}
.form-status.is-success { color: #1B7A43; }
.form-status.is-error { color: #B4232C; }

/* ---------- Footer ---------- */
.site-footer {
  border-top: 1px solid var(--color-line);
  padding-block: 28px;
}
.footer-inner {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 12px;
  font-size: 0.86rem;
  color: var(--color-ink-faint);
}
.footer-links { display: flex; gap: 10px; }
.footer-links a { color: var(--color-ink-soft); transition: color var(--transition); }
.footer-links a:hover { color: var(--color-accent); }

/* ---------- Scroll reveal ---------- */
.reveal {
  opacity: 0;
  transform: translateY(16px);
  transition: opacity 600ms ease, transform 600ms ease;
}
.reveal.is-visible {
  opacity: 1;
  transform: translateY(0);
}

/* =========================================================
   Responsive
   ========================================================= */
@media (max-width: 960px) {
  .hero-inner { grid-template-columns: 1fr; }
  .hero-portrait { max-width: 360px; order: -1; }
  .about-grid { grid-template-columns: 1fr; }
  .card-grid-3 { grid-template-columns: repeat(2, 1fr); }
  .method-steps { grid-template-columns: repeat(2, 1fr); }
  .contact-grid { grid-template-columns: 1fr; }
  .numbers-grid { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 720px) {
  .primary-nav {
    position: fixed;
    inset: 76px 0 0 0;
    background: var(--color-bg);
    padding: 24px;
    transform: translateY(-8px);
    opacity: 0;
    pointer-events: none;
    transition: opacity var(--transition), transform var(--transition);
  }
  .primary-nav.is-open {
    opacity: 1;
    transform: translateY(0);
    pointer-events: auto;
  }
  .primary-nav ul { flex-direction: column; align-items: flex-start; gap: 4px; }
  .primary-nav li { width: 100%; }
  .primary-nav a { display: block; padding: 14px 4px; width: 100%; border-bottom: 1px solid var(--color-line-soft); }
  .nav-cta { display: inline-block; margin-top: 10px; text-align: center; }
  .nav-toggle { display: flex; }

  .card-grid-2, .card-grid-3 { grid-template-columns: 1fr; }
  .method-steps { grid-template-columns: 1fr; }
  .numbers-grid { grid-template-columns: 1fr; }
  .timeline-item { grid-template-columns: 1fr; gap: 10px; }
  .contact-form { grid-template-columns: 1fr; }
  .service-list-inline { grid-template-columns: 1fr; }
}