:root {
  --bg: #eef0f6;
  --surface: #ffffff;
  --surface-2: #f6f7fb;
  --border: #e3e6f0;
  --text: #141824;
  --muted: #6b7290;
  --accent: #141824;
  --accent-text: #ffffff;
  --pink-from: #f2447a;
  --pink-mid: #f68fae;
  --pink-to: #fbd3df;
  --blue-from: #3c63f0;
  --blue-mid: #7f9cf7;
  --blue-to: #d7e0fd;
  --violet-from: #c7a2f2;
  --violet-mid: #9b6ce6;
  --violet-to: #7d4fd8;
  --success: #1f9d6b;
  --warning: #e08a00;
  --danger: #e0345e;
  --shadow: 0 10px 30px rgb(40 50 90 / 0.08);
  --code-bg: #141824;
  --code-text: #e9ecff;
}

.dark {
  --bg: #0b0d17;
  --surface: rgb(255 255 255 / 0.05);
  --surface-2: rgb(255 255 255 / 0.08);
  --border: rgb(255 255 255 / 0.1);
  --text: #e9ecff;
  --muted: #9097b8;
  --accent: #e9ecff;
  --accent-text: #0b0d17;
  --pink-from: #ff4f8b;
  --pink-mid: #a0285a;
  --pink-to: #1a0f22;
  --blue-from: #4f7bff;
  --blue-mid: #253c9e;
  --blue-to: #0e1328;
  --violet-from: #a873ff;
  --violet-mid: #5a2fb0;
  --violet-to: #130c26;
  --success: #3ddc97;
  --warning: #ffb547;
  --danger: #ff5c86;
  --shadow: none;
  --code-bg: rgb(0 0 0 / 0.45);
  --code-text: #e9ecff;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  scroll-padding-top: 32px;
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: "Manrope", system-ui, sans-serif;
  font-size: 16px;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  transition: background-color 0.4s, color 0.4s;
}

.dark body {
  background-image:
    radial-gradient(1px 1px at 20% 30%, #ffffff55 50%, transparent 51%),
    radial-gradient(1px 1px at 70% 80%, #ffffff44 50%, transparent 51%),
    radial-gradient(1px 1px at 85% 15%, #ffffff66 50%, transparent 51%),
    radial-gradient(1px 1px at 40% 70%, #ffffff33 50%, transparent 51%),
    radial-gradient(1.5px 1.5px at 60% 45%, #ffffff55 50%, transparent 51%);
  background-attachment: fixed;
}

a {
  color: inherit;
}

.dots {
  font-family: "Doto", monospace;
  font-weight: 800;
  letter-spacing: -0.02em;
  font-variant-numeric: tabular-nums;
}

.muted {
  color: var(--muted);
}

/* боковое меню */

.sidebar {
  position: fixed;
  inset: 16px auto 16px 16px;
  width: 268px;
  z-index: 20;
  display: flex;
  flex-direction: column;
  padding: 20px 14px;
  border-radius: 28px;
  background: var(--surface);
  border: 1px solid var(--border);
  box-shadow: var(--shadow);
  backdrop-filter: blur(16px);
}

.dark .sidebar {
  background: rgb(20 23 37 / 0.85);
}

.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 0 10px 18px;
  font-weight: 800;
  font-size: 18px;
}

.brand small {
  display: block;
  font-size: 12px;
  font-weight: 500;
  color: var(--muted);
}

.brand .mark {
  font-family: "Doto", monospace;
  font-size: 26px;
}

.toc {
  flex: 1;
  overflow-y: auto;
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.toc a {
  position: relative;
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 9px 12px;
  border-radius: 14px;
  text-decoration: none;
  font-size: 14px;
  font-weight: 600;
  color: var(--muted);
  transition: color 0.2s, background-color 0.2s;
}

.toc a:hover {
  color: var(--text);
  background: var(--surface-2);
}

.toc a.active {
  color: var(--accent-text);
  background: var(--accent);
}

.toc .num {
  width: 22px;
  font-family: "Doto", monospace;
  font-weight: 800;
  font-size: 13px;
  opacity: 0.8;
}

.theme-toggle {
  margin-top: 14px;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  height: 42px;
  border: 1px solid var(--border);
  border-radius: 999px;
  background: var(--surface-2);
  color: var(--text);
  font: inherit;
  font-size: 14px;
  font-weight: 600;
  cursor: pointer;
  transition: transform 0.2s;
}

.theme-toggle:active {
  transform: scale(0.97);
}

/* основная колонка */

main {
  margin-left: 300px;
  padding: 16px 40px 120px;
}

main > section {
  max-width: 1160px;
  margin-inline: auto;
}

section {
  padding-top: 72px;
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-size: 13px;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  color: var(--muted);
}

.eyebrow .dots {
  font-size: 16px;
  letter-spacing: 0;
}

h1 {
  font-size: 56px;
  line-height: 1.05;
  letter-spacing: -0.03em;
  margin: 12px 0 16px;
}

h2 {
  font-size: 36px;
  line-height: 1.15;
  letter-spacing: -0.02em;
  margin: 8px 0 12px;
}

h3 {
  font-size: 20px;
  margin: 0 0 8px;
}

p {
  margin: 0 0 12px;
}

.lead {
  font-size: 18px;
  color: var(--muted);
  max-width: 720px;
}

/* герой */

.hero {
  position: relative;
  margin-top: 0;
  padding: 64px 48px 48px;
  border-radius: 36px;
  overflow: hidden;
  background: var(--surface);
  border: 1px solid var(--border);
  box-shadow: var(--shadow);
}

.hero canvas {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  pointer-events: none;
}

.hero .blob {
  position: absolute;
  border-radius: 999px;
  filter: blur(90px);
  opacity: 0.45;
  animation: float 18s ease-in-out infinite alternate;
  pointer-events: none;
}

.dark .hero .blob {
  opacity: 0.35;
}

.hero > *:not(.blob):not(canvas) {
  position: relative;
}

@keyframes float {
  0% { transform: translate(0, 0) scale(1); }
  50% { transform: translate(40px, -30px) scale(1.1); }
  100% { transform: translate(-30px, 35px) scale(0.95); }
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 24px;
}

.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  height: 44px;
  padding: 0 20px;
  border-radius: 999px;
  border: 0;
  background: var(--accent);
  color: var(--accent-text);
  font: inherit;
  font-size: 15px;
  font-weight: 700;
  text-decoration: none;
  cursor: pointer;
  transition: transform 0.2s, opacity 0.2s;
}

.btn:hover {
  opacity: 0.9;
}

.btn:active {
  transform: scale(0.97);
}

.btn.soft {
  background: var(--surface-2);
  color: var(--text);
  border: 1px solid var(--border);
}

/* градиентные карточки */

.grid {
  display: grid;
  gap: 16px;
}

.grid.c2 { grid-template-columns: repeat(2, 1fr); }
.grid.c3 { grid-template-columns: repeat(3, 1fr); }
.grid.c4 { grid-template-columns: repeat(4, 1fr); }

.card {
  position: relative;
  padding: 24px;
  border-radius: 28px;
  background: var(--surface);
  border: 1px solid var(--border);
  box-shadow: var(--shadow);
}

.dark .card {
  backdrop-filter: blur(14px);
}

.gcard {
  position: relative;
  overflow: hidden;
  isolation: isolate;
  padding: 24px;
  border-radius: 28px;
  color: #fff;
}

.gcard::before {
  content: "";
  position: absolute;
  inset: -30%;
  z-index: -1;
  background: var(--g);
  animation: drift 18s ease-in-out infinite alternate;
}

.gcard::after {
  content: "";
  position: absolute;
  inset: 0;
  z-index: -1;
  opacity: 0.12;
  mix-blend-mode: overlay;
  background-image: url("data:image/svg+xml;utf8,<svg xmlns='http://www.w3.org/2000/svg' width='160' height='160'><filter id='n'><feTurbulence baseFrequency='.9' numOctaves='2'/></filter><rect width='100%' height='100%' filter='url(%23n)'/></svg>");
}

.pink { --g: radial-gradient(60% 55% at 50% 45%, var(--pink-from) 0%, var(--pink-mid) 50%, var(--pink-to) 100%); }
.blue { --g: radial-gradient(60% 55% at 60% 55%, var(--blue-from) 0%, var(--blue-mid) 50%, var(--blue-to) 100%); }
.violet { --g: linear-gradient(160deg, var(--violet-from) 0%, var(--violet-mid) 60%, var(--violet-to) 100%); }
.dark .pink { box-shadow: 0 0 60px rgb(255 79 139 / 0.22); }
.dark .blue { box-shadow: 0 0 60px rgb(79 123 255 / 0.22); }
.dark .violet { box-shadow: 0 0 60px rgb(168 115 255 / 0.2); }

@keyframes drift {
  0% { transform: translate(0, 0) scale(1); }
  50% { transform: translate(6%, -4%) scale(1.08); }
  100% { transform: translate(-5%, 5%) scale(1.02); }
}

.stat .value {
  display: block;
  margin-top: 18px;
  font-size: 56px;
  line-height: 1;
}

.stat .label {
  font-size: 14px;
  opacity: 0.92;
}

/* шаги */

.steps {
  display: flex;
  flex-direction: column;
  gap: 12px;
  counter-reset: step;
}

.step {
  display: grid;
  grid-template-columns: 64px 1fr;
  gap: 18px;
  align-items: start;
}

.step .n {
  display: grid;
  place-items: center;
  width: 56px;
  height: 56px;
  border-radius: 18px;
  background: var(--accent);
  color: var(--accent-text);
  font-family: "Doto", monospace;
  font-weight: 800;
  font-size: 26px;
}

.step h3 {
  margin-top: 4px;
}

/* код */

.code {
  position: relative;
  margin: 10px 0 12px;
  padding: 14px 52px 14px 18px;
  border-radius: 16px;
  background: var(--code-bg);
  color: var(--code-text);
  font-family: "JetBrains Mono", Consolas, monospace;
  font-size: 14px;
  white-space: pre-wrap;
  word-break: break-word;
}

.copy {
  position: absolute;
  top: 8px;
  right: 8px;
  height: 30px;
  padding: 0 10px;
  border: 1px solid rgb(255 255 255 / 0.15);
  border-radius: 10px;
  background: rgb(255 255 255 / 0.08);
  color: #e9ecff;
  font: inherit;
  font-size: 12px;
  cursor: pointer;
}

code {
  font-family: "JetBrains Mono", Consolas, monospace;
  font-size: 0.9em;
  padding: 1px 6px;
  border-radius: 6px;
  background: var(--surface-2);
  border: 1px solid var(--border);
}

/* подсказки */

.note {
  display: flex;
  gap: 12px;
  padding: 14px 18px;
  border-radius: 18px;
  font-size: 15px;
  background: color-mix(in srgb, var(--blue-from) 10%, transparent);
  border: 1px solid color-mix(in srgb, var(--blue-from) 30%, transparent);
}

.note.warn {
  background: color-mix(in srgb, var(--warning) 10%, transparent);
  border-color: color-mix(in srgb, var(--warning) 35%, transparent);
}

.note b:first-child {
  white-space: nowrap;
}

/* таблицы */

.table {
  width: 100%;
  border-collapse: collapse;
  font-size: 15px;
}

.table th {
  text-align: left;
  font-size: 13px;
  font-weight: 600;
  color: var(--muted);
  padding: 10px 14px;
}

.table td {
  padding: 12px 14px;
  border-top: 1px solid var(--border);
  vertical-align: top;
}

.table td:first-child {
  font-weight: 700;
  white-space: nowrap;
}

.badge {
  display: inline-flex;
  align-items: center;
  padding: 2px 10px;
  border-radius: 999px;
  font-size: 12px;
  font-weight: 700;
  background: var(--surface-2);
  color: var(--muted);
  white-space: nowrap;
}

.badge.blue { background: color-mix(in srgb, var(--blue-from) 16%, transparent); color: var(--blue-from); }
.badge.pink { background: color-mix(in srgb, var(--pink-from) 16%, transparent); color: var(--pink-from); }
.badge.green { background: color-mix(in srgb, var(--success) 16%, transparent); color: var(--success); }
.badge.amber { background: color-mix(in srgb, var(--warning) 16%, transparent); color: var(--warning); }
.badge.violet { background: color-mix(in srgb, var(--violet-from) 20%, transparent); color: var(--violet-from); }

/* экраны */

.tabs {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  margin: 18px 0;
}

.tabs button {
  height: 36px;
  padding: 0 14px;
  border-radius: 999px;
  border: 1px solid var(--border);
  background: var(--surface);
  color: var(--muted);
  font: inherit;
  font-size: 14px;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.2s;
}

.tabs button:hover {
  color: var(--text);
}

.tabs button.active {
  background: var(--accent);
  color: var(--accent-text);
  border-color: transparent;
}

.screen {
  display: grid;
  grid-template-columns: 1.6fr 1fr;
  gap: 24px;
  align-items: start;
}

.shot {
  display: block;
  width: 100%;
  border-radius: 20px;
  border: 1px solid var(--border);
  box-shadow: 0 20px 50px rgb(0 0 0 / 0.18);
  cursor: zoom-in;
  transition: transform 0.3s;
}

.shot:hover {
  transform: translateY(-3px);
}

.light-only { display: block; }
.dark-only { display: none; }
.dark .light-only { display: none; }
.dark .dark-only { display: block; }

.screen ul,
.card ul {
  margin: 8px 0 0;
  padding-left: 20px;
}

.screen li,
.card li {
  margin-bottom: 6px;
}

.fade {
  animation: fade 0.45s cubic-bezier(.16, 1, .3, 1);
}

@keyframes fade {
  from { opacity: 0; transform: translateY(10px); }
}

/* дерево файлов */

.tree {
  font-family: "JetBrains Mono", Consolas, monospace;
  font-size: 14px;
  line-height: 1.9;
}

.tree .row {
  display: grid;
  grid-template-columns: 310px 1fr;
  gap: 16px;
  padding: 0 8px;
  border-radius: 8px;
}

.tree .row:hover {
  background: var(--surface-2);
}

.tree .path {
  white-space: pre;
}

.tree .desc {
  font-family: "Manrope", system-ui, sans-serif;
  color: var(--muted);
  font-size: 14px;
}

/* формулы */

.formula {
  margin: 8px 0;
  padding: 12px 16px;
  border-radius: 14px;
  background: var(--surface-2);
  font-size: 17px;
  font-weight: 600;
}

/* диаграммы */

.diagram {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.diagram img {
  width: 100%;
  border-radius: 16px;
  background: #fff;
  cursor: zoom-in;
  border: 1px solid var(--border);
}

/* вопросы */

details {
  border-top: 1px solid var(--border);
  padding: 14px 4px;
}

details:first-of-type {
  border-top: 0;
}

summary {
  cursor: pointer;
  font-weight: 700;
  list-style: none;
  display: flex;
  justify-content: space-between;
  gap: 16px;
}

summary::after {
  content: "+";
  font-family: "Doto", monospace;
  font-size: 22px;
  line-height: 1;
  transition: transform 0.3s;
}

details[open] summary::after {
  transform: rotate(45deg);
}

details p {
  margin: 10px 0 0;
  color: var(--muted);
}

/* лайтбокс */

.lightbox {
  position: fixed;
  inset: 0;
  z-index: 50;
  display: none;
  place-items: center;
  padding: 32px;
  background: rgb(5 6 12 / 0.82);
  backdrop-filter: blur(10px);
  cursor: zoom-out;
}

.lightbox.open {
  display: grid;
  animation: fade 0.3s ease-out;
}

.lightbox img {
  max-width: 100%;
  max-height: 100%;
  border-radius: 16px;
  background: #fff;
}

/* появление при прокрутке */

.reveal {
  opacity: 0;
  transform: translateY(24px);
  filter: blur(6px);
  transition: opacity 0.7s cubic-bezier(.16, 1, .3, 1), transform 0.7s cubic-bezier(.16, 1, .3, 1), filter 0.7s;
}

.reveal.shown {
  opacity: 1;
  transform: none;
  filter: none;
}

footer {
  margin-top: 96px;
  padding-top: 24px;
  border-top: 1px solid var(--border);
  color: var(--muted);
  font-size: 14px;
}

::view-transition-old(root),
::view-transition-new(root) {
  animation: none;
  mix-blend-mode: normal;
}

@media (max-width: 1100px) {
  .sidebar { display: none; }
  main { margin-left: 0; padding: 16px 20px 80px; }
  .grid.c3, .grid.c4 { grid-template-columns: repeat(2, 1fr); }
  .screen { grid-template-columns: 1fr; }
  h1 { font-size: 40px; }
  .tree .row { grid-template-columns: 1fr; gap: 0; }
}

@media (prefers-reduced-motion: reduce) {
  .gcard::before, .hero .blob { animation: none; }
  .reveal { opacity: 1; transform: none; filter: none; }
}

/* цвета и шрифты «ОСновы» */

:root {
  --bg: #f4f5f7;
  --border: #e3e5e9;
  --text: #15171c;
  --muted: #646a74;
  --accent: #15171c;
  --pink-from: #cdee52;
  --pink-mid: #e2f594;
  --pink-to: #f3f9dc;
  --blue-from: #2e3239;
  --blue-mid: #4a4f58;
  --blue-to: #9a9fa8;
  --violet-from: #6f8f12;
  --violet-mid: #4c6b00;
  --violet-to: #26360a;
  --code-bg: #15171c;
  --code-text: #eef5d2;
  --shadow: 0 10px 30px rgb(21 23 28 / 0.07);
}

.dark {
  --bg: #0c0d0f;
  --surface: rgb(255 255 255 / 0.04);
  --surface-2: rgb(255 255 255 / 0.07);
  --border: rgb(255 255 255 / 0.09);
  --text: #e8e9eb;
  --muted: #8b8e95;
  --accent: #d9f26b;
  --accent-text: #14170a;
  --pink-from: #d9f26b;
  --pink-mid: #b4d43c;
  --pink-to: #7f9c1a;
  --blue-from: #3b3e46;
  --blue-mid: #24262b;
  --blue-to: #131417;
  --violet-from: #5d7a12;
  --violet-mid: #33440c;
  --violet-to: #15180d;
  --code-bg: rgb(0 0 0 / 0.5);
}

body,
.tree .desc {
  font-family: "Geist", system-ui, sans-serif;
}

.dots,
.toc .num,
.step .n,
.brand .mark,
summary::after {
  font-family: "Geist Mono", monospace;
  font-weight: 600;
  letter-spacing: -0.04em;
}

.brand .mark {
  display: grid;
  place-items: center;
  width: 36px;
  height: 36px;
  border-radius: 10px;
  background: #cdee52;
  color: #15190a;
  font-size: 15px;
}

.gcard.pink {
  color: #15190a;
}

.dark .pink { box-shadow: 0 0 60px rgb(217 242 107 / 0.18); }
.dark .blue { box-shadow: none; border: 1px solid var(--border); }
.dark .violet { box-shadow: 0 0 60px rgb(140 180 30 / 0.14); }

.badge.pink { background: color-mix(in srgb, #92bd14 18%, transparent); color: #4c6b00; }
.badge.violet { background: color-mix(in srgb, #4c6b00 14%, transparent); color: #4c6b00; }
.badge.blue { background: color-mix(in srgb, #2e3239 10%, transparent); color: #2e3239; }
.dark .badge.pink, .dark .badge.violet { background: rgb(217 242 107 / 0.12); color: #d9f26b; }
.dark .badge.blue { background: rgb(255 255 255 / 0.08); color: #c7c9cd; }

.note {
  background: color-mix(in srgb, #92bd14 9%, transparent);
  border-color: color-mix(in srgb, #92bd14 35%, transparent);
}


.back-home { display: block; margin: -6px 10px 14px; font-size: 13px; color: var(--muted); text-decoration: none; }
.back-home:hover { color: var(--text); }