@import url("https://fonts.googleapis.com/css2?family=Sora:wght@400;500;600;700&family=Vazirmatn:wght@400;500;600;700&display=swap");

:root {
  --bg: #0b1218;
  --bg-soft: #121c24;
  --surface: #17232d;
  --surface-2: #1d2c38;
  --border: #2a3d4c;
  --text: #e8eef2;
  --muted: #8fa3b0;
  --teal: #2f9e8a;
  --amber: #e0a045;
  --coral: #e06452;
  --sky: #3db8d0;
  --radius: 16px;
  --font-display: "Sora", "Vazirmatn", sans-serif;
  --font-body: "Vazirmatn", "Sora", sans-serif;
  --shadow: 0 20px 50px rgba(0, 0, 0, 0.35);
  --max: 1080px;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: var(--font-body);
  color: var(--text);
  background:
    radial-gradient(900px 420px at 8% -5%, rgba(47, 158, 138, 0.16), transparent 55%),
    radial-gradient(700px 380px at 95% 5%, rgba(61, 184, 208, 0.1), transparent 50%),
    linear-gradient(165deg, #0a1016, #101820 50%, #0d151c);
  background-attachment: fixed;
  line-height: 1.75;
  font-size: 1.02rem;
}

a {
  color: var(--sky);
  text-decoration: none;
}

a:hover {
  color: #9adceb;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 40;
  backdrop-filter: blur(14px);
  background: color-mix(in srgb, var(--bg) 82%, transparent);
  border-bottom: 1px solid var(--border);
}

.header-inner {
  max-width: calc(var(--max) + 80px);
  margin: 0 auto;
  padding: 0.85rem 1.25rem;
  display: flex;
  align-items: center;
  gap: 1rem;
  justify-content: space-between;
}

.brand {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  color: var(--text);
}

.brand-mark {
  width: 38px;
  height: 38px;
  border-radius: 10px;
  border: 1px solid rgba(61, 184, 208, 0.35);
  background: linear-gradient(145deg, rgba(47, 158, 138, 0.35), rgba(61, 184, 208, 0.12));
  position: relative;
}

.brand-mark::before,
.brand-mark::after {
  content: "";
  position: absolute;
  border: 2px solid var(--teal);
  border-radius: 3px;
  inset: 10px;
  transform: rotate(18deg);
}

.brand-mark::after {
  inset: 13px 13px 13px 16px;
  border-color: var(--amber);
  transform: rotate(-10deg);
}

.brand strong {
  display: block;
  font-family: var(--font-display);
  font-size: 0.95rem;
  letter-spacing: -0.02em;
}

.brand span {
  display: block;
  font-size: 0.72rem;
  color: var(--muted);
}

.nav {
  display: flex;
  flex-wrap: wrap;
  gap: 0.35rem;
  justify-content: flex-end;
}

.nav a {
  color: var(--muted);
  font-size: 0.82rem;
  font-weight: 600;
  padding: 0.4rem 0.65rem;
  border-radius: 8px;
  border: 1px solid transparent;
}

.nav a:hover,
.nav a.active {
  color: var(--text);
  background: var(--surface);
  border-color: var(--border);
}

.nav a.active {
  border-color: rgba(47, 158, 138, 0.45);
  background: rgba(47, 158, 138, 0.14);
}

.hero {
  max-width: calc(var(--max) + 80px);
  margin: 0 auto;
  padding: 3rem 1.25rem 2rem;
  display: grid;
  gap: 1.5rem;
}

.hero-grid {
  display: grid;
  grid-template-columns: 1.3fr 0.9fr;
  gap: 1.5rem;
  align-items: stretch;
}

.eyebrow {
  margin: 0 0 0.55rem;
  font-family: var(--font-display);
  font-size: 0.72rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--sky);
  font-weight: 600;
}

h1,
h2,
h3 {
  font-family: var(--font-display);
  letter-spacing: -0.02em;
  line-height: 1.25;
}

h1 {
  margin: 0 0 0.75rem;
  font-size: clamp(1.8rem, 4vw, 2.7rem);
}

h2 {
  margin: 0 0 0.75rem;
  font-size: 1.45rem;
}

h3 {
  margin: 1.25rem 0 0.45rem;
  font-size: 1.05rem;
  color: #d7e6ec;
}

.lead {
  margin: 0;
  color: var(--muted);
  font-size: 1.08rem;
  max-width: 52ch;
}

.hero-card,
.panel,
.step,
.metric,
.callout {
  background: color-mix(in srgb, var(--surface) 92%, transparent);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
}

.hero-card {
  padding: 1.25rem;
  display: flex;
  flex-direction: column;
  gap: 0.85rem;
  justify-content: center;
}

.hero-card dl {
  margin: 0;
  display: grid;
  gap: 0.55rem;
}

.hero-card dt {
  font-size: 0.75rem;
  color: var(--muted);
}

.hero-card dd {
  margin: 0.1rem 0 0;
  font-weight: 600;
}

.cta-row {
  display: flex;
  flex-wrap: wrap;
  gap: 0.55rem;
  margin-top: 1.25rem;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.65rem 1rem;
  border-radius: 10px;
  font-weight: 700;
  font-size: 0.9rem;
  border: 1px solid transparent;
}

.btn.primary {
  background: linear-gradient(135deg, #2f9e8a, #248a78);
  color: #04110e;
}

.btn.ghost {
  background: var(--surface-2);
  border-color: var(--border);
  color: var(--text);
}

.main {
  max-width: calc(var(--max) + 80px);
  margin: 0 auto;
  padding: 0 1.25rem 4rem;
}

.section {
  margin: 2rem 0 2.5rem;
}

.section-head {
  margin-bottom: 1rem;
}

.section-head p {
  margin: 0;
  color: var(--muted);
  max-width: 60ch;
}

.grid-2,
.grid-3 {
  display: grid;
  gap: 0.9rem;
}

.grid-2 {
  grid-template-columns: repeat(2, minmax(0, 1fr));
}

.grid-3 {
  grid-template-columns: repeat(3, minmax(0, 1fr));
}

.panel {
  padding: 1.15rem 1.2rem;
}

.panel p:last-child,
.step p:last-child {
  margin-bottom: 0;
}

.panel .icon,
.step .num {
  width: 2rem;
  height: 2rem;
  display: grid;
  place-items: center;
  border-radius: 8px;
  background: rgba(47, 158, 138, 0.14);
  color: var(--teal);
  font-weight: 700;
  font-size: 0.85rem;
  margin-bottom: 0.7rem;
}

.step {
  padding: 1.1rem 1.15rem;
  position: relative;
}

.step .num {
  background: rgba(61, 184, 208, 0.14);
  color: var(--sky);
}

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

.formula {
  font-family: ui-monospace, Consolas, monospace;
  background: var(--bg-soft);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 0.85rem 1rem;
  overflow-x: auto;
  direction: ltr;
  text-align: left;
  color: #cde7df;
  font-size: 0.9rem;
}

table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.92rem;
}

th,
td {
  border-bottom: 1px solid var(--border);
  padding: 0.7rem 0.55rem;
  text-align: right;
  vertical-align: top;
}

th {
  color: var(--muted);
  font-weight: 600;
  font-size: 0.8rem;
}

code,
.mono {
  font-family: ui-monospace, Consolas, monospace;
  direction: ltr;
  unicode-bidi: embed;
}

code {
  background: rgba(255, 255, 255, 0.05);
  padding: 0.1rem 0.35rem;
  border-radius: 5px;
  font-size: 0.88em;
}

pre {
  direction: ltr;
  text-align: left;
  background: var(--bg-soft);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 1rem;
  overflow-x: auto;
  color: #d5e4ea;
  font-size: 0.86rem;
  line-height: 1.55;
}

.callout {
  padding: 1rem 1.15rem;
  border-color: rgba(224, 160, 69, 0.35);
  background: rgba(224, 160, 69, 0.08);
}

.callout.danger {
  border-color: rgba(224, 100, 82, 0.4);
  background: rgba(224, 100, 82, 0.08);
}

.callout.info {
  border-color: rgba(61, 184, 208, 0.35);
  background: rgba(61, 184, 208, 0.08);
}

.metrics {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 0.75rem;
}

.metric {
  padding: 0.9rem 1rem;
}

.metric strong {
  display: block;
  font-family: var(--font-display);
  font-size: 1.25rem;
  margin-top: 0.2rem;
}

.metric span {
  color: var(--muted);
  font-size: 0.78rem;
}

.timeline {
  display: grid;
  gap: 0.75rem;
  border-right: 2px solid var(--border);
  padding-right: 1rem;
  margin-right: 0.25rem;
}

.timeline-item {
  position: relative;
}

.timeline-item::before {
  content: "";
  position: absolute;
  right: calc(-1rem - 6px);
  top: 0.45rem;
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: var(--teal);
  box-shadow: 0 0 0 4px rgba(47, 158, 138, 0.15);
}

.site-footer {
  border-top: 1px solid var(--border);
  padding: 1.5rem 1.25rem 2.5rem;
  color: var(--muted);
  font-size: 0.85rem;
}

.footer-inner {
  max-width: calc(var(--max) + 80px);
  margin: 0 auto;
  display: flex;
  justify-content: space-between;
  gap: 1rem;
  flex-wrap: wrap;
}

.tag {
  display: inline-block;
  font-size: 0.72rem;
  padding: 0.2rem 0.5rem;
  border-radius: 6px;
  border: 1px solid var(--border);
  color: #c5d4dc;
  background: var(--bg-soft);
  margin-left: 0.25rem;
}

.flow {
  display: flex;
  flex-wrap: wrap;
  gap: 0.45rem;
  align-items: center;
}

.flow .chip {
  background: var(--bg-soft);
  border: 1px solid var(--border);
  border-radius: 999px;
  padding: 0.35rem 0.7rem;
  font-size: 0.8rem;
  font-weight: 600;
}

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

.toc {
  display: grid;
  gap: 0.35rem;
}

.toc a {
  color: var(--muted);
  font-size: 0.9rem;
}

.toc a:hover {
  color: var(--sky);
}

@media (max-width: 900px) {
  .hero-grid,
  .grid-2,
  .grid-3,
  .metrics {
    grid-template-columns: 1fr;
  }

  .header-inner {
    flex-direction: column;
    align-items: flex-start;
  }

  .nav {
    justify-content: flex-start;
  }
}