/* ============================================================
   Crypto Helper — shared design system
   Dark fintech theme · brand orange + cyan accent · no build step
   ============================================================ */

:root {
  --bg: #050505;
  --bg-elevated: #0d0f14;
  --bg-card: rgba(255, 255, 255, 0.03);
  --border: rgba(255, 255, 255, 0.08);
  --border-strong: rgba(255, 255, 255, 0.14);

  --brand: #ff6b00;
  --brand-light: #ffa24d;
  --brand-grad: linear-gradient(135deg, #ff6b00 0%, #ffa24d 100%);
  --accent: #00f0ff;

  --text: #ffffff;
  --text-secondary: #a1a1aa;
  --text-muted: #62626b;

  --radius: 16px;
  --radius-lg: 24px;
  --nav-height: 72px;

  --shadow-brand: 0 8px 32px rgba(255, 107, 0, 0.28);
  --font: "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
}

*,
*::before,
*::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
  scroll-padding-top: calc(var(--nav-height) + 16px);
}

body {
  font-family: var(--font);
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

img {
  max-width: 100%;
  display: block;
}

a {
  color: inherit;
  text-decoration: none;
}

.container {
  width: min(1160px, 100% - 48px);
  margin-inline: auto;
}

/* ---------- Accessibility ---------- */

.skip-link {
  position: absolute;
  left: -9999px;
  top: 0;
  background: var(--brand);
  color: #fff;
  padding: 10px 18px;
  border-radius: 0 0 12px 0;
  z-index: 200;
}

.skip-link:focus {
  left: 0;
}

:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 3px;
  border-radius: 4px;
}

/* ---------- Navbar ---------- */

.nav {
  position: fixed;
  inset: 0 0 auto 0;
  height: var(--nav-height);
  z-index: 100;
  background: rgba(5, 5, 5, 0.72);
  -webkit-backdrop-filter: blur(18px);
  backdrop-filter: blur(18px);
  border-bottom: 1px solid var(--border);
}

.nav-inner {
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}

.nav-logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-weight: 800;
  font-size: 1.1rem;
  letter-spacing: -0.02em;
}

.nav-logo img {
  width: 34px;
  height: 34px;
  border-radius: 9px;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 28px;
  list-style: none;
}

.nav-links a {
  color: var(--text-secondary);
  font-size: 0.92rem;
  font-weight: 500;
  transition: color 0.2s;
}

.nav-links a:hover {
  color: var(--text);
}

.nav-actions {
  display: flex;
  align-items: center;
  gap: 14px;
}

.lang-toggle {
  display: flex;
  border: 1px solid var(--border-strong);
  border-radius: 999px;
  overflow: hidden;
}

.lang-toggle button {
  background: transparent;
  color: var(--text-secondary);
  border: 0;
  font: inherit;
  font-size: 0.8rem;
  font-weight: 600;
  padding: 6px 12px;
  cursor: pointer;
  transition: background 0.2s, color 0.2s;
}

.lang-toggle button.active {
  background: var(--brand);
  color: #fff;
}

.nav-burger {
  display: none;
  background: transparent;
  border: 1px solid var(--border-strong);
  border-radius: 10px;
  color: var(--text);
  width: 42px;
  height: 42px;
  font-size: 1.15rem;
  cursor: pointer;
}

/* ---------- Buttons ---------- */

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  font: inherit;
  font-weight: 600;
  font-size: 0.95rem;
  border-radius: 999px;
  padding: 13px 26px;
  cursor: pointer;
  border: 0;
  transition: transform 0.2s, box-shadow 0.2s, background 0.2s, border-color 0.2s;
}

.btn-primary {
  background: var(--brand-grad);
  color: #fff;
  box-shadow: var(--shadow-brand);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 12px 40px rgba(255, 107, 0, 0.4);
}

.btn-ghost {
  background: transparent;
  color: var(--text);
  border: 1px solid var(--border-strong);
}

.btn-ghost:hover {
  border-color: var(--brand);
  color: var(--brand-light);
}

.btn-sm {
  padding: 9px 18px;
  font-size: 0.85rem;
}

/* ---------- Cards ---------- */

.card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  -webkit-backdrop-filter: blur(10px);
  backdrop-filter: blur(10px);
  transition: transform 0.25s, border-color 0.25s, background 0.25s;
}

.card:hover {
  transform: translateY(-4px);
  border-color: rgba(255, 107, 0, 0.35);
  background: rgba(255, 255, 255, 0.05);
}

/* ---------- Sections ---------- */

.section {
  padding: 96px 0;
}

.section-label {
  display: inline-block;
  font-size: 0.78rem;
  font-weight: 700;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--brand-light);
  background: rgba(255, 107, 0, 0.1);
  border: 1px solid rgba(255, 107, 0, 0.25);
  border-radius: 999px;
  padding: 6px 14px;
  margin-bottom: 18px;
}

.section-title {
  font-size: clamp(1.7rem, 3.6vw, 2.6rem);
  font-weight: 800;
  letter-spacing: -0.03em;
  line-height: 1.15;
  margin-bottom: 14px;
}

.section-desc {
  color: var(--text-secondary);
  font-size: 1.05rem;
  max-width: 560px;
}

.section-head {
  margin-bottom: 56px;
}

.section-head.center {
  text-align: center;
}

.section-head.center .section-desc {
  margin-inline: auto;
}

.highlight {
  background: var(--brand-grad);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  color: transparent;
}

/* ---------- Footer ---------- */

.footer {
  border-top: 1px solid var(--border);
  background: var(--bg-elevated);
  padding: 64px 0 32px;
  margin-top: 40px;
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.6fr 1fr 1fr 1fr;
  gap: 40px;
  margin-bottom: 48px;
}

.footer-brand p {
  color: var(--text-secondary);
  font-size: 0.92rem;
  margin-top: 14px;
  max-width: 300px;
}

.footer h4 {
  font-size: 0.85rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--text-muted);
  margin-bottom: 16px;
}

.footer ul {
  list-style: none;
  display: grid;
  gap: 10px;
}

.footer ul a {
  color: var(--text-secondary);
  font-size: 0.92rem;
  transition: color 0.2s;
}

.footer ul a:hover {
  color: var(--brand-light);
}

.footer-bottom {
  border-top: 1px solid var(--border);
  padding-top: 26px;
  display: flex;
  justify-content: space-between;
  gap: 16px;
  flex-wrap: wrap;
  color: var(--text-muted);
  font-size: 0.85rem;
}

/* ---------- Scroll reveal ---------- */

.reveal {
  opacity: 0;
  transform: translateY(26px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

.reveal.visible {
  opacity: 1;
  transform: none;
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

  .reveal {
    opacity: 1;
    transform: none;
    transition: none;
  }

  .card:hover,
  .btn-primary:hover {
    transform: none;
  }
}

/* ---------- Legal / prose pages ---------- */

.prose-page {
  padding: calc(var(--nav-height) + 56px) 0 80px;
}

.prose {
  max-width: 760px;
  margin-inline: auto;
}

.prose h1 {
  font-size: clamp(1.9rem, 4vw, 2.6rem);
  font-weight: 800;
  letter-spacing: -0.03em;
  margin-bottom: 10px;
}

.prose .updated {
  color: var(--text-muted);
  font-size: 0.9rem;
  margin-bottom: 36px;
}

.prose h2 {
  font-size: 1.25rem;
  font-weight: 700;
  margin: 36px 0 12px;
}

.prose p,
.prose li {
  color: var(--text-secondary);
  font-size: 0.98rem;
}

.prose ul {
  padding-left: 22px;
  display: grid;
  gap: 8px;
  margin: 10px 0;
}

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

.prose a {
  color: var(--brand-light);
}

.prose a:hover {
  text-decoration: underline;
}

/* ---------- Responsive ---------- */

@media (max-width: 860px) {
  .footer-grid {
    grid-template-columns: 1fr 1fr;
  }
}

@media (max-width: 768px) {
  .nav-links {
    position: fixed;
    top: var(--nav-height);
    left: 0;
    right: 0;
    flex-direction: column;
    align-items: flex-start;
    gap: 4px;
    background: rgba(5, 5, 5, 0.97);
    border-bottom: 1px solid var(--border);
    padding: 12px 24px 20px;
    display: none;
  }

  .nav-links.open {
    display: flex;
  }

  .nav-links a {
    display: block;
    padding: 10px 0;
    font-size: 1rem;
    width: 100%;
  }

  .nav-burger {
    display: block;
  }

  .nav-download {
    display: none;
  }

  .section {
    padding: 64px 0;
  }
}

@media (max-width: 520px) {
  .footer-grid {
    grid-template-columns: 1fr;
    gap: 28px;
  }
}