:root {
  --bg: #f6f7fb;
  --card: #ffffff;
  --text: #202532;
  --muted: #677084;
  --border: #e3e7ef;
  --accent: #4f46e5;
  --accent-soft: #eef2ff;
  --green-soft: #ecfdf3;
  --green-border: #b7ebc6;
  --blue-soft: #eff6ff;
  --blue-border: #bfdbfe;
  --yellow-soft: #fffbeb;
  --yellow-border: #fde68a;
  --red-soft: #fff1f2;
  --red-border: #fecdd3;
  --shadow: 0 8px 24px rgba(18, 32, 59, 0.07);
  --radius: 18px;
  --content-width: 1120px;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: Inter, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.65;
}

.shell {
  display: grid;
  grid-template-columns: 280px 1fr;
  min-height: 100vh;
}

.sidebar {
  position: sticky;
  top: 0;
  height: 100vh;
  overflow: auto;
  padding: 28px 20px;
  background: #fff;
  border-right: 1px solid var(--border);
}

.brand {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 26px;
}

.brand-badge {
  width: 42px;
  height: 42px;
  border-radius: 14px;
  display: grid;
  place-items: center;
  background: var(--accent-soft);
  color: var(--accent);
  font-size: 22px;
  font-weight: 700;
}

.brand h1 {
  margin: 0;
  font-size: 1.05rem;
  line-height: 1.2;
}

.brand p {
  margin: 3px 0 0;
  color: var(--muted);
  font-size: 0.92rem;
}

.nav-title {
  font-size: 0.78rem;
  color: var(--muted);
  text-transform: uppercase;
  letter-spacing: 0.06em;
  margin: 0 0 10px;
}

.nav a {
  display: block;
  padding: 10px 12px;
  border-radius: 12px;
  color: var(--text);
  text-decoration: none;
  margin-bottom: 6px;
  transition: 0.18s ease;
}

.nav a:hover {
  background: var(--accent-soft);
  color: var(--accent);
}

.sidebar-note {
  margin-top: 24px;
  padding: 14px;
  border-radius: 14px;
  background: var(--yellow-soft);
  border: 1px solid var(--yellow-border);
  font-size: 0.93rem;
}

.main {
  padding: 34px;
}

.content {
  max-width: var(--content-width);
  margin: 0 auto;
}

.topbar {
  margin-bottom: 18px;
}

.back-link {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  text-decoration: none;
  color: var(--accent);
  background: #fff;
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 10px 14px;
  box-shadow: var(--shadow);
  font-weight: 600;
  transition: 0.18s ease;
}

.back-link:hover {
  background: var(--accent-soft);
}

.hero {
  background: linear-gradient(135deg, #ffffff 0%, #f3f6ff 100%);
  border: 1px solid var(--border);
  border-radius: 24px;
  padding: 30px;
  box-shadow: var(--shadow);
  margin-bottom: 24px;
}

.hero-kicker {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 12px;
  border-radius: 999px;
  background: var(--accent-soft);
  color: var(--accent);
  font-size: 0.9rem;
  font-weight: 600;
  margin-bottom: 14px;
}

.hero h2 {
  margin: 0 0 10px;
  font-size: clamp(1.8rem, 3vw, 2.5rem);
  line-height: 1.15;
}

.hero p {
  margin: 0;
  color: var(--muted);
  font-size: 1.02rem;
  max-width: 900px;
}

.section {
  margin-bottom: 24px;
  scroll-margin-top: 24px;
}

.section-card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 22px;
  box-shadow: var(--shadow);
  overflow: hidden;
}

.section-head {
  padding: 22px 24px 10px;
}

.section-head h2 {
  margin: 0 0 8px;
  font-size: 1.4rem;
}

.section-head p {
  margin: 0;
  color: var(--muted);
}

.section-body {
  padding: 0 24px 24px;
}

.info-grid,
.mini-grid,
.two-shots {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 16px;
  margin-top: 18px;
}

.quick-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 16px;
  margin: 22px 0 28px;
}

.quick-card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 18px;
  box-shadow: var(--shadow);
}

.quick-card h3 {
  margin: 0 0 6px;
  font-size: 1rem;
}

.quick-card p {
  margin: 0;
  color: var(--muted);
  font-size: 0.95rem;
}

.info-box,
.mini-card {
  border: 1px solid var(--border);
  border-radius: 16px;
  padding: 16px;
  background: #fff;
}

.info-box h3,
.mini-card h3 {
  margin: 0 0 8px;
  font-size: 1rem;
}

.info-box p,
.info-box li,
.mini-card li {
  color: var(--muted);
}

.mini-card ul,
.info-box ul {
  margin: 0;
  padding-left: 18px;
}

.steps {
  list-style: none;
  padding: 0;
  margin: 18px 0 0;
  display: grid;
  gap: 12px;
}

.steps li {
  display: grid;
  grid-template-columns: 42px 1fr;
  gap: 12px;
  align-items: start;
  padding: 14px;
  border-radius: 16px;
  border: 1px solid var(--border);
  background: #fff;
}

.step-no {
  width: 42px;
  height: 42px;
  border-radius: 12px;
  display: grid;
  place-items: center;
  font-weight: 700;
  background: var(--accent-soft);
  color: var(--accent);
}

.step-content strong {
  display: block;
  margin-bottom: 4px;
}

.rule-list {
  margin: 18px 0 0;
  padding-left: 18px;
}

.rule-list li {
  margin-bottom: 8px;
}

.shot {
  margin: 18px 0 0;
  border: 1px solid var(--border);
  border-radius: 18px;
  overflow: hidden;
  background: #fff;
  box-shadow: var(--shadow);
}

.shot img {
  display: block;
  width: 100%;
  height: auto;
}

.shot figcaption {
  padding: 14px 16px;
  color: var(--muted);
  font-size: 0.95rem;
}

.shot figcaption strong {
  color: var(--text);
}

.tip,
.warn,
.ok {
  margin-top: 18px;
  padding: 14px 16px;
  border-radius: 16px;
  border: 1px solid;
}

.tip {
  background: var(--blue-soft);
  border-color: var(--blue-border);
}

.warn {
  background: var(--yellow-soft);
  border-color: var(--yellow-border);
}

.ok {
  background: var(--green-soft);
  border-color: var(--green-border);
}

.tip strong,
.warn strong,
.ok strong {
  display: block;
  margin-bottom: 4px;
}

.footer {
  color: var(--muted);
  font-size: 0.92rem;
  text-align: center;
  padding: 14px 0 2px;
}

@media (max-width: 1024px) {
  .shell {
    grid-template-columns: 1fr;
  }

  .sidebar {
    position: static;
    height: auto;
    border-right: 0;
    border-bottom: 1px solid var(--border);
  }

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

  .info-grid,
  .mini-grid,
  .two-shots {
    grid-template-columns: 1fr 1fr;
  }
}

@media (max-width: 700px) {
  .main {
    padding: 18px;
  }

  .hero,
  .section-head,
  .section-body {
    padding-left: 18px;
    padding-right: 18px;
  }

  .quick-grid,
  .info-grid,
  .mini-grid,
  .two-shots {
    grid-template-columns: 1fr;
  }
}