/* Data Nexus — стили сайта, повторяют композицию презентации (слайд 2560×1440 → vw) */

@font-face {
  font-family: "Inter";
  src: url("../fonts/inter-cyrillic.woff2") format("woff2");
  font-weight: 100 900;
  font-style: normal;
  font-display: swap;
  unicode-range: U+0301, U+0400-045F, U+0490-0491, U+04B0-04B1, U+2116;
}
@font-face {
  font-family: "Inter";
  src: url("../fonts/inter-latin.woff2") format("woff2");
  font-weight: 100 900;
  font-style: normal;
  font-display: swap;
  unicode-range: U+0000-00FF, U+0131, U+0152-0153, U+02BB-02BC, U+02C6, U+02DA, U+02DC, U+0304, U+0308, U+0329, U+2000-206F, U+20AC, U+2122, U+2191, U+2193, U+2212, U+2215, U+FEFF, U+FFFD;
}

:root {
  /* Цвета бренда */
  --bg: #f7f1e8;
  --ink: #1a1a1a;
  --muted: #6e6b66;
  --accent: #e85a2a;
  --accent-text: #b5421a;
  --wm: #e8e2d8;
  --line-soft: rgba(26, 26, 26, 0.14);

  --rule: 1.5px;
  --pad: clamp(1rem, 3.6vw, 5.5rem);
  --max: 1920px;

  /* Логотип в шапке: линия логотипа совпадает с нижней линией шапки */
  --logo-w: clamp(190px, 17vw, 320px);
  --logo-top: clamp(12px, 1.4vw, 26px);
  --header-h: calc(var(--logo-top) + var(--logo-w) * 0.25702);

  /* Слэш-маркер */
  --mk-h: clamp(1.9rem, 3.2vw, 4rem);
  --mk-gap: clamp(2.3rem, 3.8vw, 4.75rem);

  /* Типографика по слайдам */
  --fs-body: clamp(1rem, 1.33vw, 1.6rem);
  --fs-col: clamp(1.35rem, 2.2vw, 2.65rem);
  --fs-en: clamp(1rem, 1.4vw, 1.7rem);

  --ease: cubic-bezier(0.2, 0.7, 0.2, 1);
}

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

html {
  -webkit-text-size-adjust: 100%;
  scroll-behavior: smooth;
  scroll-padding-top: calc(var(--header-h) + 1rem);
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: "Inter", "Helvetica Neue", Helvetica, Arial, sans-serif;
  font-optical-sizing: auto;
  font-size: var(--fs-body);
  line-height: 1.5;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

h1, h2, h3, p, dl, dd { margin: 0; }
img, svg { display: block; max-width: 100%; }
a { color: inherit; }
button { font: inherit; }
[hidden] { display: none !important; }
::selection { background: var(--accent); color: var(--ink); }
:focus-visible { outline: 2px solid var(--accent); outline-offset: 3px; }

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

.skip-link {
  position: absolute;
  left: 1rem;
  top: -4rem;
  z-index: 200;
  padding: 0.6rem 1rem;
  background: var(--ink);
  color: var(--bg);
  text-decoration: none;
}
.skip-link:focus { top: 1rem; }

/* Переносы строк как на слайдах — только на широких экранах */
@media (max-width: 1199px) {
  .br-d { display: none; }
}

/* ---------- Графика из презентации ---------- */

.logo { display: block; width: 100%; height: auto; overflow: visible; }

.slash {
  display: block;
  height: var(--mk-h);
  width: auto;
  aspect-ratio: 64 / 82;
  fill: var(--accent);
  overflow: visible;
}

.wm {
  position: absolute;
  right: 0;
  bottom: 0;
  z-index: 0;
  height: auto;
  color: var(--wm);
  pointer-events: none;
}

/* ---------- Кнопки (страница 404) ---------- */

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.6rem;
  min-height: 3.25rem;
  padding: 0.8rem 1.6rem;
  border: var(--rule) solid var(--ink);
  background: transparent;
  color: var(--ink);
  font-size: 1rem;
  font-weight: 600;
  line-height: 1.2;
  text-decoration: none;
  transition: background-color 0.2s, color 0.2s, border-color 0.2s;
}
.btn--primary { background: var(--ink); color: var(--bg); }
.btn--primary:hover { background: var(--accent); border-color: var(--accent); color: var(--ink); }
.btn--ghost:hover { background: var(--ink); color: var(--bg); }

/* ---------- Шапка ---------- */

.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: var(--bg);
}
.header-inner {
  position: relative;
  height: var(--header-h);
}
.header-logo {
  position: absolute;
  top: var(--logo-top);
  left: var(--pad);
  width: var(--logo-w);
  line-height: 0;
}
/* Продолжение линии логотипа до правого края */
.header-inner::after {
  content: "";
  position: absolute;
  left: calc(var(--pad) + var(--logo-w) - 1px);
  right: var(--pad);
  bottom: calc(var(--rule) / -2);
  height: var(--rule);
  background: var(--ink);
}

.site-nav {
  position: absolute;
  top: 0;
  right: var(--pad);
  bottom: 0;
  display: flex;
  align-items: center;
}
.site-nav ul { display: flex; gap: clamp(1.5rem, 2.4vw, 3rem); margin: 0; padding: 0; list-style: none; }
.site-nav ul a {
  position: relative;
  padding-block: 0.35rem;
  font-size: clamp(0.95rem, 1.1vw, 1.3rem);
  font-weight: 500;
  text-decoration: none;
}
.site-nav ul a::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  height: var(--rule);
  background: var(--accent);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform 0.25s var(--ease);
}
.site-nav ul a:hover::after,
.site-nav ul a[aria-current="page"]::after { transform: scaleX(1); }

.nav-toggle { display: none; }

@media (max-width: 900px) {
  .nav-toggle {
    position: absolute;
    top: 50%;
    right: calc(var(--pad) - 10px);
    display: inline-flex;
    flex-direction: column;
    justify-content: center;
    gap: 6px;
    width: 44px;
    height: 44px;
    padding: 10px;
    border: 0;
    background: none;
    color: var(--ink);
    transform: translateY(-50%);
    cursor: pointer;
  }
  .nav-toggle span { display: block; height: 2px; background: currentColor; transition: transform 0.25s var(--ease); }
  body.nav-open .nav-toggle span:first-child { transform: translateY(4px) rotate(45deg); }
  body.nav-open .nav-toggle span:last-child { transform: translateY(-4px) rotate(-45deg); }
  body.nav-open { overflow: hidden; }

  .site-nav {
    position: fixed;
    inset: var(--header-h) 0 0 0;
    display: none;
    align-items: stretch;
    padding: 1.5rem var(--pad) 2rem;
    background: var(--bg);
    overflow-y: auto;
  }
  body.nav-open .site-nav { display: block; }
  .site-nav ul { flex-direction: column; gap: 0; }
  .site-nav ul a {
    display: block;
    padding-block: 1rem;
    border-bottom: 1px solid var(--line-soft);
    font-size: 1.75rem;
    font-weight: 700;
    letter-spacing: -0.02em;
  }
  .site-nav ul a::after { display: none; }
  .site-nav ul a[aria-current="page"] { color: var(--accent-text); }
}

/* ---------- Слайд 1: hero ---------- */

.hero {
  position: relative;
  display: flex;
  align-items: center;
  min-height: min(calc(100svh - var(--header-h)), 56.25vw);
  padding-block: clamp(3rem, 7vw, 9rem);
  overflow: hidden;
}
.hero-inner { position: relative; z-index: 1; }
.hero-title {
  font-size: clamp(2rem, 4.76vw, 5.75rem);
  font-weight: 700;
  line-height: 1.22;
  letter-spacing: -0.02em;
}
.hero-lead {
  margin-top: clamp(1.25rem, 3vw, 3.6rem);
  font-size: clamp(1.1rem, 2.2vw, 2.65rem);
  line-height: 1.33;
}

/* ---------- Слайды 2–5 ---------- */

.slide { position: relative; overflow: hidden; }
.slide > .container { position: relative; z-index: 1; }
.slide-inner {
  position: relative;
  padding-block: clamp(2.5rem, 3.9vw, 4.75rem) clamp(4rem, 7.5vw, 9rem);
  border-top: var(--rule) solid var(--ink);
}
.slide--first .slide-inner { border-top: 0; }

.slide-title {
  --fs: clamp(2.3rem, 7.2vw, 8.6rem);
  margin-bottom: clamp(2rem, 4.3vw, 5.2rem);
  font-size: var(--fs);
  font-weight: 700;
  line-height: 1.08;
  letter-spacing: -0.025em;
  overflow-wrap: break-word;
}
.slide--principles .slide-title { --fs: clamp(2.3rem, 6.3vw, 7.6rem); margin-bottom: clamp(2rem, 3.4vw, 4.1rem); }
.slide--approach .slide-title { --fs: clamp(2.3rem, 6.7vw, 8rem); margin-bottom: clamp(1.75rem, 3.6vw, 4.3rem); }
.slide--contacts .slide-title { --fs: clamp(2.6rem, 7.4vw, 8.9rem); margin-bottom: clamp(2rem, 4.4vw, 5.3rem); }

.slide-num {
  position: absolute;
  right: 0;
  bottom: clamp(1.25rem, 2.2vw, 2.6rem);
  font-size: clamp(0.95rem, 1.74vw, 2.1rem);
  font-variant-numeric: tabular-nums;
  line-height: 1;
}

/* Блок со слэшем: слэш стоит на базовой линии первой строки заголовка */
.feature-title,
.keywords li { position: relative; }
.feature-title > .slash,
.keywords li > .slash {
  position: absolute;
  left: calc(-1 * var(--mk-gap));
  top: calc(0.938em - var(--mk-h));
}
.keywords li > .slash { left: 0; }

.feature {
  padding-left: var(--mk-gap);
  padding-top: max(0px, calc(var(--mk-h) - 0.938 * var(--fs-col)));
}
.feature-title {
  font-size: var(--fs-col);
  font-weight: 700;
  line-height: 1.15;
  letter-spacing: -0.025em;
}
.feature-en { margin-top: clamp(0.5rem, 1vw, 1.2rem); color: var(--ink); font-size: var(--fs-en); line-height: 1.35; }
.feature-text { margin-top: clamp(0.9rem, 1.9vw, 2.3rem); font-size: var(--fs-body); line-height: 1.5; }

/* Слайд 2: три колонки с вертикальными линиями */
.cols-3 { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); }
.cols-3 .feature { padding-right: clamp(0.75rem, 1.2vw, 1.5rem); padding-bottom: clamp(0.5rem, 1.2vw, 1.5rem); }
.cols-3 .feature + .feature {
  padding-left: calc(clamp(1.25rem, 2.2vw, 2.7rem) + var(--mk-gap));
  border-left: var(--rule) solid var(--ink);
}

/* Слайд 3: сетка 2×2 с перекрестьем линий */
.grid-2 { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); }
.grid-2 .feature { padding-right: clamp(1rem, 2vw, 2.5rem); }
.grid-2 .feature:nth-child(even) { padding-left: calc(clamp(1.5rem, 4vw, 4.8rem) + var(--mk-gap)); }
.grid-2 .feature:nth-child(odd) { border-right: var(--rule) solid var(--ink); }
.grid-2 .feature:nth-child(-n+2) { padding-bottom: clamp(1.75rem, 2.7vw, 3.25rem); border-bottom: var(--rule) solid var(--ink); }
.grid-2 .feature:nth-child(n+3) { padding-top: calc(clamp(1.75rem, 2.1vw, 2.5rem) + max(0px, calc(var(--mk-h) - 0.938 * var(--fs-col)))); padding-bottom: clamp(0.5rem, 1.2vw, 1.5rem); }

/* Слайд 4 */
.approach-text p { font-size: clamp(1.05rem, 1.74vw, 2.1rem); line-height: 1.5; }
.approach-text p + p { margin-top: clamp(1.1rem, 2.6vw, 3.1rem); }

.keywords {
  display: flex;
  flex-wrap: nowrap;
  margin: clamp(2.5rem, 4.6vw, 5.5rem) 0 0;
  padding: 0;
  list-style: none;
  --kw-fs: clamp(1.3rem, 2.54vw, 3.05rem);
}
.keywords li {
  margin-right: clamp(2rem, 7vw, 8.4rem);
  padding-left: var(--mk-gap);
  white-space: nowrap;
  font-size: var(--kw-fs);
  font-weight: 700;
  line-height: 1.15;
  letter-spacing: -0.015em;
}
.keywords li:last-child { margin-right: 0; }

/* Слайд 5: контакты */
.req { display: grid; gap: clamp(1.4rem, 3vw, 3.6rem); }
.req dt { margin-bottom: clamp(0.25rem, 0.9vw, 1.1rem); color: var(--muted); font-size: clamp(0.95rem, 1.6vw, 1.9rem); line-height: 1.3; }
.req dd { font-size: clamp(1.15rem, 2.38vw, 2.85rem); font-weight: 700; line-height: 1.2; letter-spacing: -0.01em; overflow-wrap: anywhere; }
.req-num { font-variant-numeric: tabular-nums; }
.req a { text-decoration: none; transition: color 0.2s; }
.req a:hover { color: var(--accent-text); }

@media (max-width: 900px) {
  .cols-3, .grid-2 { grid-template-columns: minmax(0, 1fr); }
  .cols-3 .feature + .feature,
  .grid-2 .feature + .feature {
    margin-top: 2rem;
    padding-top: calc(2rem + max(0px, calc(var(--mk-h) - 0.938 * var(--fs-col))));
    padding-left: var(--mk-gap);
    border-left: 0;
    border-top: var(--rule) solid var(--ink);
  }
  .grid-2 .feature:nth-child(odd) { border-right: 0; }
  .grid-2 .feature:nth-child(-n+2) { padding-bottom: 0; border-bottom: 0; }
  .cols-3 .feature, .grid-2 .feature { padding-right: 0; padding-bottom: 0; }
  .keywords { flex-direction: column; gap: 1.1rem; }
  .keywords li { margin-right: 0; }
  .slide-num { bottom: 1.25rem; }
}

/* ---------- Внутренние страницы ---------- */

.page-hero {
  position: relative;
  overflow: hidden;
  padding-block: clamp(2.5rem, 5vw, 6rem) clamp(2rem, 3.5vw, 4rem);
}
.page-hero .container { position: relative; z-index: 1; }
.page-title {
  font-size: clamp(2.3rem, 6vw, 7rem);
  font-weight: 700;
  line-height: 1.05;
  letter-spacing: -0.025em;
  overflow-wrap: break-word;
}
.page-date { margin-top: 1rem; color: var(--muted); font-size: clamp(0.95rem, 1.2vw, 1.4rem); }
.page-lead { max-width: 34em; margin-top: clamp(1.25rem, 2.5vw, 2rem); font-size: clamp(1.1rem, 1.74vw, 2.1rem); line-height: 1.5; }
.page-actions { display: flex; flex-wrap: wrap; gap: 0.75rem; margin-top: clamp(2rem, 3.5vw, 3rem); }
.page-hero--404 { padding-bottom: clamp(5rem, 12vw, 12rem); }

.doc-layout { display: grid; grid-template-columns: minmax(14rem, 18vw) minmax(0, 1fr); gap: clamp(2rem, 6vw, 7rem); align-items: start; }
.doc-aside { position: sticky; top: calc(var(--header-h) + 2rem); }
.doc-nav { margin: 0; padding: 0; list-style: none; border-top: var(--rule) solid var(--ink); }
.doc-nav a {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  padding: 0.9rem 0;
  border-bottom: 1px solid var(--line-soft);
  font-size: 1rem;
  font-weight: 500;
  line-height: 1.3;
  text-decoration: none;
}
.slash--sm { height: 1.1rem; flex: none; opacity: 0; transition: opacity 0.2s; }
.doc-nav a:hover .slash--sm, .doc-nav a[aria-current="page"] .slash--sm { opacity: 1; }
.doc-nav a[aria-current="page"] { font-weight: 700; }

.doc { max-width: 50rem; padding-bottom: clamp(4rem, 8vw, 8rem); font-size: clamp(1rem, 1.15vw, 1.2rem); line-height: 1.7; }
.doc h2 {
  margin: 2.75rem 0 1rem;
  padding-top: 1.5rem;
  border-top: 1px solid var(--line-soft);
  font-size: clamp(1.3rem, 1.8vw, 1.9rem);
  font-weight: 700;
  line-height: 1.2;
  letter-spacing: -0.015em;
}
.doc h2:first-child { margin-top: 0; padding-top: 0; border-top: 0; }
.doc p, .doc ul { margin: 0 0 1rem; }
.doc ul { padding-left: 1.25rem; }
.doc li { margin-bottom: 0.45rem; padding-left: 0.25rem; }
.doc li::marker { color: var(--accent); }
.doc a { text-decoration-color: var(--accent); text-decoration-thickness: 1.5px; text-underline-offset: 3px; overflow-wrap: anywhere; }
.doc a:hover { color: var(--accent-text); }
.doc-note { padding: 1.25rem 1.5rem; border-left: 3px solid var(--accent); background: rgba(232, 226, 216, 0.6); }

@media (max-width: 900px) {
  .doc-layout { grid-template-columns: minmax(0, 1fr); }
  .doc-aside { position: static; }
}

/* ---------- Подвал ---------- */

.site-footer { padding-block: 0 2rem; }
.footer-top {
  display: grid;
  grid-template-columns: 1.6fr 1fr 1.1fr 1.3fr;
  gap: 2.5rem;
  padding-top: clamp(2rem, 4vw, 3.5rem);
  border-top: var(--rule) solid var(--ink);
}
.footer-logo { display: block; width: clamp(150px, 12vw, 230px); }
.footer-logo .logo-rule { display: none; }
.footer-brand p { max-width: 22rem; margin-top: 1.25rem; color: var(--muted); font-size: 0.95rem; }
.footer-h { margin: 0 0 1rem; color: var(--muted); font-size: 0.88rem; font-weight: 500; }
.footer-col ul { display: grid; gap: 0.65rem; margin: 0; padding: 0; list-style: none; font-size: 0.95rem; line-height: 1.45; }
.footer-col a { text-decoration: none; transition: color 0.2s; }
.footer-col a:hover { color: var(--accent-text); }
.footer-bottom {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 0.75rem 2rem;
  margin-top: clamp(2.5rem, 5vw, 4rem);
  padding-top: 1.5rem;
  border-top: 1px solid var(--line-soft);
  color: var(--muted);
  font-size: 0.85rem;
}

@media (max-width: 1000px) {
  .footer-top { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}
@media (max-width: 560px) {
  .footer-top { grid-template-columns: minmax(0, 1fr); gap: 2rem; }
}

/* ---------- Анимация появления ---------- */

.js [data-reveal] {
  opacity: 0;
  transform: translateY(16px);
  transition: opacity 0.7s var(--ease), transform 0.7s var(--ease);
  transition-delay: calc(var(--d, 0) * 90ms);
}
.js [data-reveal].is-visible { opacity: 1; transform: none; }

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { transition: none !important; }
  .js [data-reveal] { opacity: 1; transform: none; }
}