/* Yelingo marketing site.
   Persian-first and right-to-left throughout — the page is authored in
   Persian and never mirrored back to LTR. Plain CSS on purpose: this is a
   static brochure, and a build step would only add moving parts. */

:root {
  --green: #58cc02;
  --green-dark: #46a302;
  --blue: #1cb0f6;
  --blue-dark: #1191cf;
  --gold: #ffc800;
  --ink: #14212b;
  --ink-soft: #5b6b78;
  --line: #e3e9ee;
  --bg: #ffffff;
  --bg-tint: #f5f9fc;
  --radius: 18px;
  --shadow: 0 10px 30px rgba(20, 33, 43, .08);
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  /* System fonts only. A hosted Persian webfont would be prettier, but
     every common CDN is unreliable from Iran, and a font that fails to
     load is worse than one that was never requested. Vazirmatn is listed
     first for the many Iranian users who already have it installed. */
  font-family: Vazirmatn, "IRANSans", Tahoma, "Segoe UI", system-ui, sans-serif;
  font-size: 17px;
  line-height: 1.9;
  -webkit-font-smoothing: antialiased;
}

img { max-width: 100%; height: auto; }

h1, h2, h3 { line-height: 1.5; margin: 0; font-weight: 800; }
h1 { font-size: clamp(30px, 6vw, 52px); letter-spacing: -.5px; }
h2 { font-size: clamp(24px, 4vw, 34px); }
h3 { font-size: 19px; }
p { margin: 0; }

.wrap { width: min(1120px, 100% - 40px); margin-inline: auto; }
.narrow { width: min(760px, 100% - 40px); }

/* ---------- buttons ---------- */

.btn {
  display: inline-block;
  background: var(--green);
  color: #fff;
  text-decoration: none;
  font-weight: 800;
  padding: 14px 30px;
  border-radius: 15px;
  box-shadow: 0 4px 0 var(--green-dark);
  transition: transform .12s ease, box-shadow .12s ease;
}
.btn:hover { transform: translateY(1px); box-shadow: 0 3px 0 var(--green-dark); }
.btn:active { transform: translateY(4px); box-shadow: none; }

.btn-lg { padding: 17px 44px; font-size: 19px; }
.btn-small { padding: 9px 20px; font-size: 15px; box-shadow: 0 3px 0 var(--green-dark); }

.btn-ghost {
  background: #fff;
  color: var(--blue);
  border: 2px solid var(--line);
  box-shadow: 0 4px 0 var(--line);
}
.btn-ghost:hover { box-shadow: 0 3px 0 var(--line); }

.btn-disabled {
  background: var(--line);
  color: var(--ink-soft);
  box-shadow: none;
  cursor: default;
  pointer-events: none;
}

/* ---------- header ---------- */

.topbar {
  position: sticky;
  top: 0;
  z-index: 20;
  background: rgba(255, 255, 255, .92);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--line);
}
.topbar-inner {
  display: flex;
  align-items: center;
  gap: 18px;
  padding: 12px 0;
}
.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  font-weight: 800;
  font-size: 20px;
  color: var(--ink);
  text-decoration: none;
}
.brand img { border-radius: 11px; }
.topnav { display: flex; gap: 22px; margin-inline-start: auto; }
.topnav a { color: var(--ink-soft); text-decoration: none; font-weight: 600; font-size: 15px; }
.topnav a:hover { color: var(--blue); }

/* ---------- hero ---------- */

.hero {
  background: linear-gradient(180deg, #f0f9ff 0%, #ffffff 100%);
  padding: clamp(40px, 7vw, 84px) 0;
}
.hero-inner {
  display: grid;
  grid-template-columns: 1.15fr .85fr;
  gap: 40px;
  align-items: center;
}
.pill {
  display: inline-block;
  background: #e4f5ff;
  color: var(--blue-dark);
  font-weight: 700;
  font-size: 14px;
  padding: 6px 16px;
  border-radius: 100px;
  margin-bottom: 18px;
}
.lead { color: var(--ink-soft); font-size: 18px; margin-top: 16px; }
.hero-actions { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 28px; }
.hero-note { color: var(--ink-soft); font-size: 14px; margin-top: 16px; }
.hero-art { text-align: center; }
.hero-art img { filter: drop-shadow(0 18px 30px rgba(20, 33, 43, .16)); }

/* ---------- stat strip ---------- */

.strip { background: var(--ink); color: #fff; }
.strip-inner {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 18px;
  padding: 26px 0;
  text-align: center;
}
.strip-inner strong { display: block; font-size: 24px; color: var(--gold); }
.strip-inner span { font-size: 14px; color: #b9c6d1; }

/* ---------- sections ---------- */

.section { padding: clamp(48px, 7vw, 88px) 0; }
.section-tint { background: var(--bg-tint); }
.section h2 { text-align: center; }
.section-lead {
  text-align: center;
  color: var(--ink-soft);
  max-width: 620px;
  margin: 14px auto 0;
}

.cards {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(230px, 1fr));
  gap: 20px;
  margin-top: 42px;
}
.card {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 26px 22px;
  text-align: center;
  box-shadow: var(--shadow);
}
.card img { margin-bottom: 10px; }
.card p { color: var(--ink-soft); font-size: 15px; margin-top: 8px; }

/* ---------- lesson anatomy ---------- */

.anatomy {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 18px;
  margin-top: 42px;
}
.anatomy article {
  position: relative;
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 26px 22px 22px;
}
.anatomy-num {
  position: absolute;
  top: -14px;
  inset-inline-start: 22px;
  width: 32px;
  height: 32px;
  display: grid;
  place-items: center;
  border-radius: 50%;
  background: var(--green);
  color: #fff;
  font-weight: 800;
  font-size: 15px;
  box-shadow: 0 3px 0 var(--green-dark);
}
.anatomy h3 { margin-top: 6px; }
.anatomy p { color: var(--ink-soft); font-size: 15px; margin-top: 8px; }

/* ---------- CEFR ---------- */

.levels { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 22px; }
.levels span {
  background: #e4f5ff;
  color: var(--blue-dark);
  font-weight: 800;
  padding: 8px 18px;
  border-radius: 11px;
  letter-spacing: .5px;
}
.levels-note { font-size: 14px; margin-top: 14px; }

/* ---------- design note ---------- */

.design-note {
  display: flex;
  gap: 24px;
  align-items: flex-start;
}
.design-note h2 { text-align: start; }
.design-note p { color: var(--ink-soft); margin-top: 12px; }
.design-fine { font-size: 13px; opacity: .8; }

@media (max-width: 700px) {
  .design-note { flex-direction: column; align-items: center; text-align: center; }
  .design-note h2 { text-align: center; }
}

/* ---------- steps ---------- */

.steps { list-style: none; margin: 40px 0 0; padding: 0; display: grid; gap: 18px; }
.steps li {
  display: flex;
  gap: 18px;
  align-items: flex-start;
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 22px;
}
.step-num {
  flex: none;
  width: 42px;
  height: 42px;
  display: grid;
  place-items: center;
  border-radius: 50%;
  background: var(--blue);
  color: #fff;
  font-weight: 800;
}
.steps p { color: var(--ink-soft); font-size: 15px; margin-top: 4px; }

/* ---------- split ---------- */

.split {
  display: grid;
  grid-template-columns: .8fr 1.2fr;
  gap: 40px;
  align-items: center;
}
.split-art { text-align: center; }
.split-copy p { color: var(--ink-soft); margin-top: 14px; }
.ticks { list-style: none; padding: 0; margin: 20px 0 0; display: grid; gap: 10px; }
.ticks li { position: relative; padding-inline-start: 30px; color: var(--ink-soft); }
.ticks li::before {
  content: "✓";
  position: absolute;
  inset-inline-start: 0;
  color: var(--green);
  font-weight: 800;
}

/* ---------- cta ---------- */

.section-cta { background: var(--bg-tint); }
.cta { text-align: center; }
.cta img { border-radius: 24px; box-shadow: var(--shadow); }
.cta h2 { margin-top: 18px; }
.cta p { color: var(--ink-soft); margin-top: 10px; }
.cta .btn { margin-top: 26px; }
.cta-note { font-size: 14px; margin-top: 18px; }

/* ---------- faq ---------- */

details {
  border: 1px solid var(--line);
  border-radius: 14px;
  padding: 16px 20px;
  margin-top: 12px;
  background: #fff;
}
details[open] { box-shadow: var(--shadow); }
summary { cursor: pointer; font-weight: 700; list-style: none; }
summary::-webkit-details-marker { display: none; }
summary::after {
  content: "+";
  float: left;
  color: var(--blue);
  font-weight: 800;
  font-size: 20px;
}
details[open] summary::after { content: "−"; }
details p { color: var(--ink-soft); font-size: 15px; margin-top: 10px; }
.narrow h2 { text-align: center; margin-bottom: 30px; }

/* ---------- footer ---------- */

.footer { background: var(--ink); color: #b9c6d1; padding: 30px 0; }
.footer-inner {
  display: flex;
  flex-wrap: wrap;
  gap: 16px;
  align-items: center;
  justify-content: space-between;
}
.footer-brand { display: flex; align-items: center; gap: 12px; }
.footer-brand strong { display: block; color: #fff; font-size: 17px; }
.footer-brand span { font-size: 14px; }
.footer-copy { font-size: 14px; }

/* ---------- responsive ---------- */

@media (max-width: 860px) {
  .hero-inner, .split { grid-template-columns: 1fr; }
  .hero-art { order: -1; }
  .hero-art img { width: 240px; }
  .strip-inner { grid-template-columns: repeat(2, 1fr); gap: 22px; }
  .topnav { display: none; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .btn { transition: none; }
}

.design-diff {
  background: #fff;
  border: 1px solid var(--line);
  border-inline-start: 4px solid var(--green);
  border-radius: 14px;
  padding: 16px 18px;
}