/* IT247 / AIT247 — shared layout, typography, components, motion.
   See /root/dev/it247_relaunch/docs/design_system.md for the full spec this implements. */

/* ---------- reset ---------- */
*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  background: var(--bg-0);
  color: var(--fg-0);
  font: 400 1.0625rem/1.6 var(--font-sans);
  -webkit-font-smoothing: antialiased;
}
h1, h2, h3, p, ul, ol, blockquote { margin: 0; }
ul { padding: 0; list-style: none; }
a { color: inherit; text-decoration: none; }
img, svg { display: block; max-width: 100%; }
button { font: inherit; color: inherit; background: none; border: 0; cursor: pointer; }

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

/* ---------- layout ---------- */
.container {
  max-width: var(--container-max);
  margin-inline: auto;
  padding-inline: var(--container-pad);
}

.site-header {
  padding-block: var(--space-4);
  border-bottom: 1px solid var(--line);
}
.site-header .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-4);
}
.site-header--sticky {
  position: sticky;
  top: 0;
  z-index: 10;
  background: rgba(11, 13, 16, 0.9);
  backdrop-filter: none; /* no glassmorphism — flat translucency only */
}

main { display: block; }

.section {
  padding-block: var(--space-9);
  border-bottom: 1px solid var(--line);
}
.section:last-of-type { border-bottom: 0; }
@media (min-width: 960px) {
  .section { padding-block: var(--space-10); }
}

.section-head {
  margin-bottom: var(--space-7);
}
.section-meta {
  display: block;
  font: 500 0.8125rem/1.4 var(--font-mono);
  letter-spacing: 0.02em;
  text-transform: uppercase;
  color: var(--fg-2);
  margin-bottom: var(--space-3);
}

.prose {
  max-width: 640px;
}
.prose p + p { margin-top: var(--space-4); }

/* ait247 is denser / more modular than it247 */
.section--dense { padding-block: var(--space-7); }
@media (min-width: 960px) {
  .section--dense { padding-block: var(--space-8); }
}
.section--dense .prose { max-width: 720px; }

/* ---------- typography roles ---------- */
.h1 {
  font: 600 clamp(2.5rem, 5vw + 1rem, 4.5rem)/1.05 var(--font-sans);
  letter-spacing: -0.01em;
}
.h2 {
  font: 600 clamp(1.5rem, 2vw + 1rem, 2.25rem)/1.15 var(--font-sans);
  letter-spacing: -0.005em;
}
.h3 {
  font: 600 1.25rem/1.3 var(--font-sans);
}
.lede {
  font-size: 1.0625rem;
  color: var(--fg-0);
}
.body-small {
  font-size: 0.9375rem;
  line-height: 1.55;
  color: var(--fg-1);
}
.mono-label {
  font: 500 0.8125rem/1.4 var(--font-mono);
  letter-spacing: 0.02em;
  text-transform: uppercase;
}
.mono-metric {
  font: 500 clamp(1.5rem, 1.5vw + 1rem, 2rem)/1.1 var(--font-mono);
}
.accent-word { color: var(--accent); }

/* ---------- wordmark / logo-morph ---------- */
.wordmark {
  display: inline-flex;
  align-items: baseline;
  font: 500 1rem/1 var(--font-mono);
  letter-spacing: 0.02em;
  text-transform: uppercase;
  color: var(--fg-0);
}
.wordmark .morph-a {
  display: inline-block;
  overflow: hidden;
  width: 0;
  opacity: 0;
  transition: width 350ms ease-out, opacity 350ms ease-out;
}
.wordmark.is-final .morph-a,
.bridge.morphed .morph-a {
  width: 1ch;
  opacity: 1;
}

/* ---------- statusline ---------- */
.statusline {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  font: 500 0.8125rem/1.4 var(--font-mono);
  letter-spacing: 0.02em;
  color: var(--fg-1);
}
.statusline .dot {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--accent);
  flex-shrink: 0;
  animation: pulse 2.4s ease-in-out infinite;
}
.statusline .caret {
  display: inline-block;
  animation: caret-blink 1s step-end 3;
}

/* ---------- buttons ---------- */
.btn-primary {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  background: var(--accent);
  color: var(--accent-on);
  border-radius: 4px;
  padding: 14px 28px;
  font: 600 1rem/1 var(--font-sans);
  transition: background 150ms ease;
}
.btn-primary:hover,
.btn-primary:focus-visible { background: var(--accent-dim); }

.btn-secondary {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  border: 1px solid var(--line-strong);
  color: var(--fg-0);
  border-radius: 4px;
  padding: 13px 27px;
  font: 500 0.8125rem/1 var(--font-mono);
  letter-spacing: 0.02em;
  text-transform: uppercase;
  transition: border-color 150ms ease;
}
.btn-secondary:hover,
.btn-secondary:focus-visible { border-color: var(--accent); }

.cta-row {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-4);
  align-items: center;
}

/* ---------- cards ---------- */
.card-grid {
  display: grid;
  gap: var(--space-5);
  grid-template-columns: 1fr;
}
@media (min-width: 640px) {
  .card-grid { grid-template-columns: repeat(2, 1fr); }
}
@media (min-width: 960px) {
  .card-grid--3 { grid-template-columns: repeat(3, 1fr); }
}

.card {
  background: var(--bg-1);
  border: 1px solid var(--line);
  border-top: 2px solid transparent;
  padding: var(--space-6);
  transition: border-top-color 150ms ease;
}
.card:hover,
.card:focus-within { border-top-color: var(--accent); }
.card .mono-label { color: var(--fg-2); display: block; margin-bottom: var(--space-4); }
.card .h3 { margin-bottom: var(--space-3); }
.card .body-small { color: var(--fg-1); }
.card .icon {
  width: 28px;
  height: 28px;
  margin-bottom: var(--space-4);
  color: var(--fg-1);
}
.card .icon svg { width: 100%; height: 100%; }

/* ---------- timeline ---------- */
.timeline {
  position: relative;
  padding-left: var(--space-6);
  border-left: 1px solid var(--line);
}
.timeline-item {
  position: relative;
  padding-bottom: var(--space-6);
}
.timeline-item:last-child { padding-bottom: 0; }
.timeline-item::before {
  content: "";
  position: absolute;
  left: calc(-1 * var(--space-6) - 4px);
  top: 6px;
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--accent-dim);
}
.timeline-item .mono-label {
  display: block;
  color: var(--fg-2);
  margin-bottom: var(--space-2);
}

/* ---------- process steps (ait247 "как работаем") ---------- */
.steps {
  display: grid;
  gap: var(--space-5);
  grid-template-columns: 1fr;
}
@media (min-width: 640px) {
  .steps { grid-template-columns: repeat(2, 1fr); }
}
@media (min-width: 1180px) {
  .steps { grid-template-columns: repeat(4, 1fr); }
}
.step {
  border-top: 1px solid var(--line-strong);
  padding-top: var(--space-4);
}
.step .mono-label { color: var(--accent); display: block; margin-bottom: var(--space-3); }

/* ---------- disclaimer ("honesty tag") ---------- */
.disclaimer {
  border-left: 2px solid var(--accent-dim);
  padding-left: var(--space-4);
  font: 400 0.9375rem/1.55 var(--font-sans);
  color: var(--fg-1);
  margin-top: var(--space-6);
}

/* ---------- bridge component ---------- */
.bridge {
  border: 1px solid var(--line-strong);
  padding: var(--space-7);
}
.bridge .statusline { margin-bottom: var(--space-4); }
.bridge .wordmark { font-size: 1.25rem; margin-bottom: var(--space-4); }
.bridge .h2 { margin-bottom: var(--space-3); }
.bridge .prose { margin-bottom: var(--space-6); }

.bridge-line {
  font-style: italic;
  color: var(--fg-1);
  max-width: 560px;
}
.bridge-line + .bridge-link { margin-top: var(--space-3); display: inline-block; }
.bridge-link {
  border-bottom: 1px solid var(--line-strong);
  transition: border-color 150ms ease;
}
.bridge-link:hover,
.bridge-link:focus-visible { border-color: var(--accent); }

/* ---------- trust line (ait247 hero) ---------- */
.trust-line {
  font: 500 0.9375rem/1.5 var(--font-mono);
  color: var(--fg-1);
}

/* ---------- procedural background (very quiet dot-grid) ---------- */
.hero {
  position: relative;
  padding-block: var(--space-9);
  overflow: hidden;
}
@media (min-width: 960px) {
  .hero { padding-block: var(--space-10); }
}
.hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image: radial-gradient(var(--fg-1) 1px, transparent 1px);
  background-size: 28px 28px;
  opacity: 0.06;
  pointer-events: none;
  animation: drift 40s linear infinite;
}
.hero > .container { position: relative; }

.hero .statusline { margin-bottom: var(--space-6); }
.hero .h1 { margin-bottom: var(--space-4); }
.hero .subtitle {
  font: 400 1.25rem/1.4 var(--font-sans);
  color: var(--fg-1);
  margin-bottom: var(--space-5);
  max-width: 640px;
}
.hero .lede { max-width: 640px; margin-bottom: var(--space-6); }
.hero .cta-row { margin-bottom: var(--space-3); }
.hero .microcopy { color: var(--fg-1); max-width: 520px; }

/* ---------- footer ---------- */
.site-footer {
  padding-block: var(--space-8);
  background: var(--bg-0);
}
.footer-cols {
  display: grid;
  gap: var(--space-6);
  grid-template-columns: 1fr;
  margin-bottom: var(--space-6);
}
@media (min-width: 640px) {
  .footer-cols { grid-template-columns: repeat(3, 1fr); }
}
.footer-cols h3 {
  font: 500 0.8125rem/1.4 var(--font-mono);
  letter-spacing: 0.02em;
  text-transform: uppercase;
  color: var(--fg-2);
  margin-bottom: var(--space-3);
}
.footer-cols p { color: var(--fg-1); font-size: 0.9375rem; line-height: 1.55; }
.footer-cols p + p { margin-top: var(--space-2); }
.footer-cols a { border-bottom: 1px solid var(--line-strong); }
.footer-cols a:hover,
.footer-cols a:focus-visible { border-color: var(--accent); }

.copyright {
  color: var(--fg-2);
  font-size: 0.875rem;
  border-top: 1px solid var(--line);
  padding-top: var(--space-5);
}

/* ---------- scroll reveal ---------- */
.reveal {
  opacity: 0;
  transform: translateY(8px);
  transition: opacity 400ms ease-out, transform 400ms ease-out;
}
.reveal.is-visible {
  opacity: 1;
  transform: translateY(0);
}

/* ---------- motion keyframes ---------- */
@keyframes pulse {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.4; }
}
@keyframes caret-blink {
  0%, 100% { opacity: 1; }
  50% { opacity: 0; }
}
@keyframes drift {
  0% { background-position: 0 0; }
  100% { background-position: 28px 56px; }
}

/* ---------- reduced motion ---------- */
@media (prefers-reduced-motion: reduce) {
  * {
    animation-duration: 0.001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.001ms !important;
    scroll-behavior: auto !important;
  }
  .reveal { opacity: 1; transform: none; }
  .hero::before { animation: none; }
  .statusline .dot { animation: none; opacity: 1; }
  .statusline .caret { display: none; }
}