/* ===================================================================
   F3 VPN — global styles
   Palette: violet (#7C3AED) + cyan (#22D3EE) on deep indigo (#0F0E1A)
   Type: Inter (body/headings) + IBM Plex Mono (eyebrows/accents)
   Mood: tech, slightly hacker, dark mesh, glassmorphism cards
   =================================================================== */

:root {
  --primary: #7C3AED;
  --primary-soft: #6D28D9;
  --accent: #22D3EE;
  --accent-soft: #06B6D4;
  --bg: #0F0E1A;
  --bg-alt: #1A1928;
  --bg-elev: #1F1D33;
  --bg-card: rgba(28, 26, 55, 0.7);
  --text: #E0E0FF;
  --text-strong: #F8F8FC;
  --text-muted: #94A3B8;
  --border: rgba(124, 58, 237, 0.22);
  --border-soft: rgba(148, 163, 184, 0.14);
  --radius: 14px;
  --radius-lg: 22px;
  --radius-sm: 8px;
  --grad: linear-gradient(135deg, #7C3AED 0%, #22D3EE 100%);
  --grad-soft: linear-gradient(135deg, rgba(124, 58, 237, 0.18) 0%, rgba(34, 211, 238, 0.18) 100%);
  --shadow-glow: 0 22px 60px -22px rgba(124, 58, 237, 0.55);
  --shadow-card: 0 18px 50px -18px rgba(8, 6, 28, 0.85);
  --mono: 'IBM Plex Mono', ui-monospace, SFMono-Regular, Menlo, monospace;
  --sans: 'Inter', system-ui, -apple-system, sans-serif;
}

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

html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }

body {
  font-family: var(--sans);
  font-size: 16px;
  line-height: 1.65;
  color: var(--text);
  background: var(--bg);
  background-image:
    radial-gradient(900px 500px at 12% -8%, rgba(124, 58, 237, 0.18), transparent 60%),
    radial-gradient(800px 460px at 92% 6%, rgba(34, 211, 238, 0.12), transparent 60%);
  background-attachment: fixed;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

img { max-width: 100%; height: auto; display: block; }
a { color: inherit; text-decoration: none; }
button { font-family: inherit; cursor: pointer; border: 0; background: transparent; color: inherit; }

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 22px;
}

.eyebrow {
  font-family: var(--mono);
  font-size: 12px;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--accent);
  display: inline-flex;
  align-items: center;
  gap: 8px;
}
.eyebrow::before {
  content: '';
  width: 22px;
  height: 1px;
  background: var(--accent);
  display: inline-block;
}

h1, h2, h3, h4 {
  font-family: var(--sans);
  color: var(--text-strong);
  font-weight: 800;
  letter-spacing: -0.02em;
  line-height: 1.12;
}

h1 { font-size: clamp(38px, 6vw, 64px); }
h2 { font-size: clamp(28px, 4vw, 42px); }
h3 { font-size: clamp(18px, 2vw, 22px); }

p { color: var(--text); }

/* ============== BUTTONS — gradient violet→cyan (axis Buttons F) ============== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 9px;
  padding: 14px 26px;
  border-radius: var(--radius);
  font-family: var(--sans);
  font-weight: 700;
  font-size: 15px;
  letter-spacing: 0.01em;
  cursor: pointer;
  transition: transform 0.22s ease, box-shadow 0.22s ease, filter 0.22s ease;
  white-space: nowrap;
  position: relative;
  overflow: hidden;
}

.btn-primary {
  background: var(--grad);
  color: #0B0A18;
  font-weight: 800;
  box-shadow: var(--shadow-glow);
}
.btn-primary:hover {
  transform: translateY(-2px);
  filter: brightness(1.08) saturate(1.1);
  box-shadow: 0 28px 70px -22px rgba(34, 211, 238, 0.55);
}

.btn-ghost {
  background: rgba(255, 255, 255, 0.04);
  color: var(--text-strong);
  border: 1px solid var(--border);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
}
.btn-ghost:hover {
  border-color: var(--accent);
  color: var(--accent);
  transform: translateY(-2px);
}

.btn-arrow::after {
  content: '→';
  font-family: var(--mono);
  display: inline-block;
  transition: transform 0.22s ease;
}
.btn-arrow:hover::after { transform: translateX(4px); }

/* ============== HEADER (Nav D — dark sticky) ============== */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(15, 14, 26, 0.86);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  border-bottom: 1px solid var(--border-soft);
}
.nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 16px 0;
}
.brand {
  display: flex;
  align-items: center;
  gap: 11px;
  font-family: var(--mono);
  font-weight: 700;
  font-size: 17px;
  letter-spacing: 0.02em;
  color: var(--text-strong);
}
.brand-mark {
  width: 36px;
  height: 36px;
  border-radius: 10px;
  background: var(--grad);
  display: grid;
  place-items: center;
  font-family: var(--mono);
  font-weight: 800;
  font-size: 14px;
  color: #0B0A18;
  box-shadow: 0 6px 20px -6px rgba(124, 58, 237, 0.7);
}
.nav-links {
  display: flex;
  align-items: center;
  gap: 30px;
  list-style: none;
}
.nav-links a {
  color: var(--text);
  font-size: 14px;
  font-weight: 500;
  transition: color 0.18s ease;
  font-family: var(--mono);
}
.nav-links a:hover { color: var(--accent); }
.nav-links a.nav-cta {
  padding: 11px 22px;
  border-radius: 10px;
  background: var(--grad);
  color: #000000;
  font-weight: 800;
  font-family: var(--sans);
}
.nav-links a.nav-cta:hover {
  color: #000000;
  filter: brightness(1.08);
  transform: translateY(-1px);
}

.burger {
  display: none;
  flex-direction: column;
  gap: 5px;
  padding: 9px;
}
.burger span {
  width: 24px;
  height: 2px;
  background: var(--text-strong);
  border-radius: 2px;
  transition: transform 0.25s ease, opacity 0.25s ease;
}
.burger.active span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.burger.active span:nth-child(2) { opacity: 0; }
.burger.active span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

.mobile-menu {
  display: none;
  position: fixed;
  top: 70px;
  left: 0;
  right: 0;
  background: rgba(15, 14, 26, 0.97);
  backdrop-filter: blur(18px);
  -webkit-backdrop-filter: blur(18px);
  padding: 28px;
  border-bottom: 1px solid var(--border-soft);
  z-index: 99;
}
.mobile-menu.open { display: block; }
.mobile-menu ul { list-style: none; display: flex; flex-direction: column; gap: 18px; }
.mobile-menu a { color: var(--text); font-family: var(--mono); font-size: 15px; }

/* ============== HERO (Hero H — animated mesh, Price D — embedded) ============== */
.hero {
  position: relative;
  padding: 96px 0 110px;
  overflow: hidden;
}
.mesh {
  position: absolute;
  inset: -10% -5% -5% -5%;
  z-index: 0;
  pointer-events: none;
  filter: blur(70px);
  opacity: 0.65;
}
.mesh .blob {
  position: absolute;
  border-radius: 50%;
  mix-blend-mode: screen;
  animation: float 18s ease-in-out infinite;
}
.mesh .blob-1 { top: -8%; left: 4%; width: 460px; height: 460px; background: radial-gradient(closest-side, rgba(124, 58, 237, 0.85), transparent); animation-delay: 0s; }
.mesh .blob-2 { top: 18%; right: -6%; width: 540px; height: 540px; background: radial-gradient(closest-side, rgba(34, 211, 238, 0.7), transparent); animation-delay: -6s; }
.mesh .blob-3 { bottom: -16%; left: 22%; width: 520px; height: 520px; background: radial-gradient(closest-side, rgba(168, 85, 247, 0.6), transparent); animation-delay: -12s; }
.mesh .blob-4 { bottom: 4%; right: 18%; width: 380px; height: 380px; background: radial-gradient(closest-side, rgba(34, 211, 238, 0.55), transparent); animation-delay: -3s; }

@keyframes float {
  0%, 100% { transform: translate(0, 0) scale(1); }
  33% { transform: translate(40px, -36px) scale(1.08); }
  66% { transform: translate(-32px, 26px) scale(0.94); }
}

.hero-grid-overlay {
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(124, 58, 237, 0.05) 1px, transparent 1px),
    linear-gradient(90deg, rgba(124, 58, 237, 0.05) 1px, transparent 1px);
  background-size: 56px 56px;
  z-index: 1;
  pointer-events: none;
  mask-image: radial-gradient(ellipse at center, #000 30%, transparent 75%);
  -webkit-mask-image: radial-gradient(ellipse at center, #000 30%, transparent 75%);
}

.hero-inner {
  position: relative;
  z-index: 2;
  text-align: center;
  max-width: 920px;
  margin: 0 auto;
}
.hero h1 { margin: 18px 0 22px; }
.hero h1 .grad {
  background: var(--grad);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}
.hero-desc {
  font-size: clamp(16px, 1.4vw, 19px);
  color: var(--text);
  max-width: 720px;
  margin: 0 auto 30px;
}
.hero-cta {
  display: flex;
  gap: 14px;
  justify-content: center;
  flex-wrap: wrap;
  margin-bottom: 26px;
}
.hero-price-tag {
  display: inline-flex;
  align-items: center;
  gap: 14px;
  padding: 12px 22px;
  background: var(--bg-card);
  backdrop-filter: blur(18px);
  -webkit-backdrop-filter: blur(18px);
  border: 1px solid var(--border);
  border-radius: 999px;
  font-family: var(--mono);
  font-size: 13px;
  color: var(--text);
  margin-bottom: 38px;
}
.hero-price-tag b { color: var(--accent); font-weight: 700; }
.hero-price-tag .dot { width: 6px; height: 6px; border-radius: 50%; background: var(--accent); box-shadow: 0 0 10px var(--accent); }

.trust-row {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 14px;
  max-width: 880px;
  margin: 0 auto;
}
.trust {
  padding: 14px 16px;
  background: var(--bg-card);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  border: 1px solid var(--border);
  border-radius: 12px;
  text-align: left;
}
.trust .k {
  display: block;
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--text-muted);
  margin-bottom: 4px;
}
.trust .v {
  font-weight: 700;
  font-size: 15px;
  color: var(--text-strong);
}

/* ============== STATS BAR ============== */
.stats {
  padding: 56px 0;
  border-top: 1px solid var(--border-soft);
  border-bottom: 1px solid var(--border-soft);
  background: var(--bg-alt);
}
.stats-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 22px;
}
.stat {
  text-align: center;
}
.stat .num {
  font-family: var(--mono);
  font-size: clamp(30px, 4vw, 42px);
  font-weight: 700;
  background: var(--grad);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
  display: block;
  margin-bottom: 6px;
}
.stat .lbl {
  font-size: 13px;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.12em;
  font-family: var(--mono);
}

/* ============== SECTION GENERIC ============== */
.section { padding: 96px 0; }
.section-head {
  text-align: center;
  max-width: 720px;
  margin: 0 auto 56px;
}
.section-head .eyebrow { margin-bottom: 14px; }
.section-head p { color: var(--text-muted); margin-top: 14px; font-size: 17px; }

/* ============== FEATURES (Cards D — glassmorphism) ============== */
.features-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 22px;
}
.feature {
  position: relative;
  padding: 32px 28px;
  background: var(--bg-card);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-card);
  transition: transform 0.3s ease, border-color 0.3s ease;
}
.feature::before {
  content: '';
  position: absolute;
  inset: 0;
  border-radius: var(--radius-lg);
  padding: 1px;
  background: var(--grad);
  -webkit-mask: linear-gradient(#000 0 0) content-box, linear-gradient(#000 0 0);
          mask: linear-gradient(#000 0 0) content-box, linear-gradient(#000 0 0);
  -webkit-mask-composite: xor;
          mask-composite: exclude;
  opacity: 0;
  transition: opacity 0.3s ease;
  pointer-events: none;
}
.feature:hover { transform: translateY(-4px); }
.feature:hover::before { opacity: 0.55; }
.feature-icon {
  width: 52px;
  height: 52px;
  border-radius: 13px;
  background: var(--grad-soft);
  border: 1px solid var(--border);
  display: grid;
  place-items: center;
  margin-bottom: 18px;
  font-family: var(--mono);
  font-weight: 700;
  font-size: 18px;
  color: var(--accent);
}
.feature h3 { margin-bottom: 9px; }
.feature p { color: var(--text-muted); font-size: 15px; line-height: 1.65; }

/* ============== DOWNLOAD / PLATFORMS ============== */
.platforms-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 18px;
}
.platform {
  padding: 26px 24px;
  background: var(--bg-card);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border: 1px solid var(--border-soft);
  border-radius: var(--radius);
  display: flex;
  align-items: center;
  gap: 18px;
  transition: transform 0.25s ease, border-color 0.25s ease;
  text-decoration: none;
  color: inherit;
}
.platform:hover {
  transform: translateY(-3px);
  border-color: var(--accent);
}
.platform-icon {
  width: 46px;
  height: 46px;
  border-radius: 11px;
  background: rgba(124, 58, 237, 0.16);
  border: 1px solid var(--border);
  display: grid;
  place-items: center;
  font-family: var(--mono);
  font-weight: 700;
  font-size: 13px;
  color: var(--accent);
  flex-shrink: 0;
}
.platform-text .ttl { font-weight: 700; color: var(--text-strong); margin-bottom: 2px; font-size: 16px; }
.platform-text .sub { font-size: 12px; color: var(--text-muted); font-family: var(--mono); letter-spacing: 0.05em; }

/* ============== WHY-F3 (text block) ============== */
.why {
  background: var(--bg-alt);
  border-top: 1px solid var(--border-soft);
  border-bottom: 1px solid var(--border-soft);
}
.why-grid {
  display: grid;
  grid-template-columns: 1.05fr 1fr;
  gap: 60px;
  align-items: start;
}
.why-text p { margin-bottom: 16px; color: var(--text); font-size: 16px; }
.why-text p:last-child { margin-bottom: 0; }
.why-text strong { color: var(--text-strong); font-weight: 700; }
.why-text code {
  font-family: var(--mono);
  font-size: 13px;
  padding: 2px 7px;
  background: rgba(124, 58, 237, 0.18);
  border: 1px solid var(--border);
  border-radius: 5px;
  color: var(--accent);
}
.why-list {
  display: flex;
  flex-direction: column;
  gap: 14px;
}
.why-item {
  padding: 20px 22px;
  background: var(--bg-card);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border: 1px solid var(--border);
  border-radius: 12px;
}
.why-item .key {
  font-family: var(--mono);
  font-size: 11px;
  text-transform: uppercase;
  letter-spacing: 0.16em;
  color: var(--accent);
  margin-bottom: 6px;
  display: block;
}
.why-item h3 { font-size: 17px; margin-bottom: 5px; }
.why-item p { color: var(--text-muted); font-size: 14px; margin: 0; }

/* ============== USE CASES ============== */
.cases-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 22px;
}
.case {
  padding: 30px 26px;
  background: var(--bg-card);
  backdrop-filter: blur(18px);
  -webkit-backdrop-filter: blur(18px);
  border: 1px solid var(--border-soft);
  border-radius: var(--radius);
  transition: transform 0.25s ease, border-color 0.25s ease;
}
.case:hover { transform: translateY(-3px); border-color: var(--primary); }
.case-tag {
  display: inline-block;
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--accent);
  padding: 4px 10px;
  border: 1px solid var(--border);
  border-radius: 999px;
  margin-bottom: 14px;
}
.case h3 { font-size: 18px; margin-bottom: 9px; }
.case p { color: var(--text-muted); font-size: 14px; line-height: 1.7; }

/* ============== CTA BANNER ============== */
.cta-banner {
  padding: 80px 0;
}
.cta-card {
  position: relative;
  padding: 68px 40px;
  border-radius: var(--radius-lg);
  background: linear-gradient(135deg, rgba(124, 58, 237, 0.18), rgba(34, 211, 238, 0.12));
  border: 1px solid var(--border);
  text-align: center;
  overflow: hidden;
}
.cta-card::before {
  content: '';
  position: absolute;
  inset: -50%;
  background:
    radial-gradient(420px 280px at 18% 30%, rgba(124, 58, 237, 0.55), transparent),
    radial-gradient(420px 280px at 82% 70%, rgba(34, 211, 238, 0.45), transparent);
  filter: blur(60px);
  z-index: 0;
}
.cta-card > * { position: relative; z-index: 1; }
.cta-card h2 { margin-bottom: 14px; }
.cta-card p { color: var(--text); font-size: 17px; margin-bottom: 30px; max-width: 580px; margin-left: auto; margin-right: auto; }

/* ============== FAQ (Accordion — axis A) ============== */
.faq-list {
  max-width: 820px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 12px;
}
.faq-item {
  background: var(--bg-card);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border: 1px solid var(--border-soft);
  border-radius: var(--radius);
  overflow: hidden;
  transition: border-color 0.25s ease;
}
.faq-item.open { border-color: var(--primary); }
.faq-q {
  width: 100%;
  padding: 22px 26px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 18px;
  text-align: left;
  font-weight: 600;
  font-size: 16px;
  color: var(--text-strong);
  cursor: pointer;
}
.faq-q .num {
  font-family: var(--mono);
  font-size: 12px;
  color: var(--accent);
  margin-right: 14px;
  letter-spacing: 0.08em;
}
.faq-toggle {
  width: 30px;
  height: 30px;
  border-radius: 50%;
  background: rgba(124, 58, 237, 0.18);
  border: 1px solid var(--border);
  display: grid;
  place-items: center;
  flex-shrink: 0;
  transition: transform 0.3s ease, background 0.3s ease;
}
.faq-toggle::before, .faq-toggle::after {
  content: '';
  position: absolute;
  width: 11px;
  height: 2px;
  background: var(--accent);
  border-radius: 1px;
}
.faq-toggle::after { transform: rotate(90deg); transition: transform 0.3s ease; }
.faq-item.open .faq-toggle { background: var(--grad); }
.faq-item.open .faq-toggle::before, .faq-item.open .faq-toggle::after { background: #0B0A18; }
.faq-item.open .faq-toggle::after { transform: rotate(0deg); }
.faq-a {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.4s ease;
}
.faq-a-inner { padding: 0 26px 24px; color: var(--text-muted); font-size: 15px; line-height: 1.75; }

/* ============== FOOTER (Footer B — single row minimal) ============== */
.site-footer {
  padding: 30px 0;
  border-top: 1px solid var(--border-soft);
  background: var(--bg-alt);
}
.footer-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 22px;
  flex-wrap: wrap;
  font-size: 13px;
  color: var(--text-muted);
  font-family: var(--mono);
}
.footer-row a { color: var(--text-muted); transition: color 0.18s ease; }
.footer-row a:hover { color: var(--accent); }
.footer-links { display: flex; gap: 22px; flex-wrap: wrap; }

/* ============== ANIMATIONS — fade-in + scale (axis Anim B) ============== */
.reveal {
  opacity: 0;
  transform: translateY(22px) scale(0.97);
  transition: opacity 0.7s ease, transform 0.7s ease;
}
.reveal.visible {
  opacity: 1;
  transform: translateY(0) scale(1);
}

/* ============== INSTRUCTION PAGE ============== */
.instr-hero {
  padding: 90px 0 60px;
  text-align: center;
  position: relative;
}
.instr-hero h1 { margin: 16px 0 18px; }
.instr-hero p { color: var(--text-muted); max-width: 720px; margin: 0 auto; font-size: 17px; }

.steps {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 26px;
  margin-top: 30px;
}
.step {
  padding: 38px 32px;
  background: var(--bg-card);
  backdrop-filter: blur(18px);
  -webkit-backdrop-filter: blur(18px);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  position: relative;
}
.step-num {
  position: absolute;
  top: -18px;
  left: 32px;
  width: 50px;
  height: 50px;
  border-radius: 14px;
  background: var(--grad);
  display: grid;
  place-items: center;
  font-family: var(--mono);
  font-weight: 800;
  color: #0B0A18;
  font-size: 18px;
  box-shadow: 0 12px 28px -10px rgba(124, 58, 237, 0.7);
}
.step h2 { font-size: 24px; margin: 16px 0 12px; }
.step p { color: var(--text-muted); font-size: 15px; line-height: 1.75; margin-bottom: 14px; }
.step .btn { margin-top: 6px; }

.after-pay {
  margin-top: 30px;
  padding: 38px 32px;
  background: var(--bg-card);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
}
.after-pay h2 { font-size: 26px; margin-bottom: 16px; }
.after-pay > p { color: var(--text-muted); margin-bottom: 22px; }

/* ============== RESPONSIVE ============== */
@media (max-width: 960px) {
  .features-grid, .platforms-grid, .cases-grid { grid-template-columns: repeat(2, 1fr); }
  .why-grid { grid-template-columns: 1fr; gap: 32px; }
  .steps { grid-template-columns: 1fr; }
  .stats-grid { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 720px) {
  .nav-links { display: none; }
  .burger { display: flex; }
  .hero { padding: 60px 0 70px; }
  .section { padding: 64px 0; }
  .features-grid, .platforms-grid, .cases-grid { grid-template-columns: 1fr; }
  .trust-row { grid-template-columns: repeat(2, 1fr); }
  .cta-card { padding: 44px 22px; }
  .footer-row { justify-content: center; text-align: center; }
}

@media (max-width: 420px) {
  .hero h1 { font-size: 34px; }
  .hero-cta { flex-direction: column; }
  .hero-cta .btn { width: 100%; }
  .stats-grid { grid-template-columns: 1fr; gap: 14px; }
  .trust-row { grid-template-columns: 1fr; }
}