/* ============================================================
   OsonVPN — design system
   Calm & trustworthy. One accent (indigo).
   Metaphor: a quiet tunnel/route beneath the noise.
   ============================================================ */

@import url('https://fonts.googleapis.com/css2?family=IBM+Plex+Sans:wght@400;500;600;700&family=IBM+Plex+Mono:wght@400;500&display=swap');

:root{
  --font-sans: "IBM Plex Sans", system-ui, -apple-system, sans-serif;
  --font-mono: "IBM Plex Mono", ui-monospace, "SFMono-Regular", monospace;

  --bg:        oklch(0.991 0.004 264);
  --surface:   oklch(1 0 0);
  --surface-2: oklch(0.975 0.005 264);
  --ink:       oklch(0.255 0.022 266);
  --ink-2:     oklch(0.46 0.018 266);
  --ink-3:     oklch(0.60 0.014 266);
  --line:      oklch(0.915 0.006 266);
  --line-2:    oklch(0.875 0.008 266);

  --accent:        oklch(0.52 0.16 266);
  --accent-hover:  oklch(0.45 0.16 266);
  --accent-press:  oklch(0.40 0.15 266);
  --accent-ink:    oklch(0.985 0.01 266);
  --accent-soft:   oklch(0.955 0.028 266);
  --accent-line:   oklch(0.86 0.06 266);

  --radius:    14px;
  --radius-sm:  9px;
  --radius-lg: 22px;
  --shadow-sm: 0 1px 2px oklch(0.3 0.04 266 / 0.06), 0 1px 1px oklch(0.3 0.04 266 / 0.04);
  --shadow-md: 0 4px 14px oklch(0.3 0.04 266 / 0.07), 0 2px 5px oklch(0.3 0.04 266 / 0.05);
  --shadow-lg: 0 18px 50px oklch(0.3 0.05 266 / 0.12), 0 6px 18px oklch(0.3 0.05 266 / 0.07);

  --maxw: 1160px;
  --gap: clamp(16px, 4vw, 28px);
  --section-y: clamp(56px, 9vw, 104px);
}

*{ box-sizing: border-box; }
*::selection{ background: var(--accent-soft); color: var(--accent-press); }
html{ -webkit-text-size-adjust: 100%; text-size-adjust: 100%; scroll-behavior: smooth; }
@media (prefers-reduced-motion: reduce){ html{ scroll-behavior: auto; } }

body{
  margin: 0;
  font-family: var(--font-sans);
  background: var(--bg);
  color: var(--ink);
  font-size: 17px;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

h1,h2,h3,h4{ margin: 0; line-height: 1.1; letter-spacing: -0.02em; font-weight: 600; color: var(--ink); text-wrap: balance; }
p{ margin: 0; text-wrap: pretty; }
a{ color: inherit; text-decoration: none; }
.mono{ font-family: var(--font-mono); }

/* ---- Layout ---- */
.wrap{ width: 100%; max-width: var(--maxw); margin-inline: auto; padding-inline: clamp(18px, 5vw, 40px); }
.section{ padding-block: var(--section-y); }
.eyebrow{
  font-family: var(--font-mono);
  font-size: 12.5px;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--accent);
  font-weight: 500;
  display: inline-flex;
  align-items: center;
  gap: 8px;
}
.eyebrow::before{ content:""; width: 22px; height: 1.5px; background: var(--accent-line); display:inline-block; }
.lead{ color: var(--ink-2); font-size: clamp(17px, 1.6vw, 19px); max-width: 56ch; }

/* ---- Buttons ---- */
.btn{
  display: inline-flex; align-items: center; justify-content: center; gap: 9px;
  font-family: var(--font-sans); font-weight: 600; font-size: 16px; line-height: 1;
  padding: 14px 22px; border-radius: 11px; border: 1px solid transparent;
  background: var(--accent); color: var(--accent-ink); cursor: pointer;
  transition: background .16s ease, transform .12s ease, box-shadow .16s ease;
  box-shadow: var(--shadow-sm); text-align: center; white-space: nowrap;
}
.btn:hover{ background: var(--accent-hover); transform: translateY(-1px); box-shadow: var(--shadow-md); }
.btn:active{ background: var(--accent-press); transform: translateY(0); }
.btn--lg{ padding: 16px 28px; font-size: 17px; }
.btn--ghost{ background: transparent; color: var(--ink); border-color: var(--line-2); box-shadow: none; }
.btn--ghost:hover{ background: var(--surface-2); border-color: var(--ink-3); }

.textlink{
  color: var(--accent); font-weight: 500; display: inline-flex; align-items: center; gap: 6px;
  border-bottom: 1px solid transparent; transition: border-color .15s ease;
}
.textlink:hover{ border-color: var(--accent-line); }

:where(a,button,input,textarea,[tabindex]):focus-visible{
  outline: 2.5px solid var(--accent); outline-offset: 2px; border-radius: 6px;
}

/* ============================================================ Header ============================================================ */
.site-header{
  position: sticky; top: 0; z-index: 50;
  background: oklch(0.991 0.004 264 / 0.82);
  -webkit-backdrop-filter: saturate(160%) blur(16px);
  backdrop-filter: saturate(160%) blur(16px);
  border-bottom: 1px solid transparent;
  transition: border-color .2s ease, box-shadow .2s ease;
}
.site-header[data-scrolled="1"]{ border-bottom-color: var(--line); box-shadow: 0 1px 0 oklch(0.3 0 0 / 0.02); }
.nav{ display: flex; align-items: center; gap: 18px; height: 68px; }

.brand{ display: inline-flex; align-items: center; gap: 10px; font-weight: 600; font-size: 18px; letter-spacing: -0.01em; }
.brand .mark{ width: 26px; height: 26px; flex: none; }
.brand b.ds{ color: var(--accent); }

.nav-links{ display: flex; align-items: center; gap: 4px; margin-left: 14px; }
.nav-links a{
  color: var(--ink-2); font-size: 15.5px; font-weight: 500; padding: 8px 12px; border-radius: 8px;
  transition: color .15s ease, background .15s ease;
}
.nav-links a:hover{ color: var(--ink); background: var(--surface-2); }
.nav-links a[aria-current="page"]{ color: var(--ink); }

.nav-right{ margin-left: auto; display: flex; align-items: center; gap: 10px; }

.lang{
  display: inline-flex; align-items: center; padding: 3px 3px 3px 7px; gap: 2px;
  background: var(--surface-2); border: 1px solid var(--line); border-radius: 9px;
}
.lang-globe{ width: 15px; height: 15px; color: var(--ink-3); margin-right: 3px; flex: none; }
.lang button{
  appearance: none; border: 0; background: transparent; cursor: pointer;
  font-family: var(--font-mono); font-size: 12px; font-weight: 500; letter-spacing: 0.04em;
  color: var(--ink-3); padding: 5px 9px; border-radius: 6px; transition: all .14s ease;
}
.lang button[aria-pressed="true"]{ background: var(--surface); color: var(--ink); box-shadow: var(--shadow-sm); }

.menu-btn{
  display: none; appearance: none; border: 1px solid var(--line); background: var(--surface);
  width: 42px; height: 42px; border-radius: 10px; cursor: pointer; align-items: center; justify-content: center;
}
.menu-btn svg{ width: 20px; height: 20px; stroke: var(--ink); fill: none; stroke-linecap: round; }
.menu-btn--close{ display: inline-flex; }

/* ============================================================ Hero ============================================================ */
.hero{ padding-top: clamp(36px, 6vw, 72px); padding-bottom: clamp(40px, 7vw, 80px); }
.hero-grid{
  display: grid; grid-template-columns: 1.05fr 0.95fr; gap: clamp(28px, 5vw, 64px); align-items: center;
}
.hero h1{ font-size: clamp(36px, 5.6vw, 62px); margin-top: 18px; }
.hero .lead{ margin-top: 22px; font-size: clamp(17px, 1.7vw, 20px); }
.hero-cta{ margin-top: 32px; display: flex; flex-wrap: wrap; align-items: center; gap: 14px; }
.hero-trust{
  margin-top: 26px; display: flex; align-items: center; gap: 10px; flex-wrap: wrap;
  color: var(--ink-3); font-size: 14px; font-family: var(--font-mono);
}
.hero-trust .dot{ width: 4px; height: 4px; border-radius: 50%; background: var(--ink-3); }

.tunnel{
  position: relative; aspect-ratio: 5 / 4; width: 100%;
  border-radius: var(--radius-lg);
  background: radial-gradient(120% 100% at 50% 42%, oklch(1 0 0) 0%, var(--surface-2) 60%, var(--surface-2) 100%);
  border: 1px solid var(--line); box-shadow: var(--shadow-lg); overflow: hidden;
}
.tunnel svg{ position: absolute; inset: 0; width: 100%; height: 100%; display: block; }
.tunnel .frame{ fill: none; stroke: var(--accent); }
.tunnel .flow{ fill: none; stroke: var(--accent); transform-box: view-box; transform-origin: 300px 205px; opacity: 0; }
.tunnel .packet{ fill: var(--accent); transform-box: view-box; transform-origin: 300px 205px; }
.tunnel .noise circle{ fill: var(--ink-3); }
.tunnel .caption{
  position: absolute; left: 16px; bottom: 14px; font-family: var(--font-mono);
  font-size: 11.5px; color: var(--ink-3); letter-spacing: 0.02em;
  background: oklch(1 0 0 / 0.6); padding: 3px 8px; border-radius: 6px;
  -webkit-backdrop-filter: blur(6px); backdrop-filter: blur(6px);
}

@media (prefers-reduced-motion: no-preference){
  .tunnel .flow{ animation: flow 6.5s cubic-bezier(.4,0,.2,1) infinite; }
  .tunnel .flow.f2{ animation-delay: 2.16s; }
  .tunnel .flow.f3{ animation-delay: 4.33s; }
  .tunnel .packet{ animation: packet 6.5s cubic-bezier(.4,0,.5,1) infinite; }
  @keyframes flow{
    0%   { transform: scale(0.12); opacity: 0; }
    18%  { opacity: 0.55; }
    82%  { opacity: 0.04; }
    100% { transform: scale(1.18); opacity: 0; }
  }
  @keyframes packet{
    0%   { transform: translate(0,0) scale(0.3); opacity: 0; }
    14%  { opacity: 1; }
    86%  { opacity: 1; }
    100% { transform: translate(0,232px) scale(1.5); opacity: 0; }
  }
}
@media (prefers-reduced-motion: reduce){
  .tunnel .flow{ opacity: 0.3; }
  .tunnel .flow.f1{ transform: scale(0.45); }
  .tunnel .flow.f2{ transform: scale(0.75); }
  .tunnel .flow.f3{ transform: scale(1.05); }
  .tunnel .packet{ opacity: 1; transform: translate(0,118px) scale(0.9); }
}

/* ============================================================ Section headings ============================================================ */
.section-head{ max-width: 60ch; margin-bottom: clamp(32px, 5vw, 52px); }
.section-head h2{ font-size: clamp(28px, 3.6vw, 42px); margin-top: 14px; }
.section-head .lead{ margin-top: 16px; }

/* ============================================================ How it works ============================================================ */
.steps{ display: grid; grid-template-columns: repeat(3, 1fr); gap: var(--gap); }
.step{
  position: relative; background: var(--surface); border: 1px solid var(--line);
  border-radius: var(--radius); padding: 28px 26px 30px; box-shadow: var(--shadow-sm);
  transition: box-shadow .2s ease, transform .2s ease, border-color .2s ease;
}
.step:hover{ box-shadow: var(--shadow-md); transform: translateY(-2px); border-color: var(--line-2); }
.step .num{
  font-family: var(--font-mono); font-size: 14px; font-weight: 500;
  color: var(--accent); display: inline-flex; align-items: center; justify-content: center;
  width: 38px; height: 38px; border-radius: 10px; background: var(--accent-soft);
  border: 1px solid var(--accent-line); margin-bottom: 20px;
}
.step h3{ font-size: 21px; margin-bottom: 8px; }
.step p{ color: var(--ink-2); font-size: 15.5px; }

/* ============================================================ Why / Features ============================================================ */
.why-grid{ display: grid; grid-template-columns: repeat(2, 1fr); gap: var(--gap); }
.feature{
  background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius);
  padding: 30px 28px; box-shadow: var(--shadow-sm);
  transition: box-shadow .2s ease, transform .2s ease, border-color .2s ease;
}
.feature:hover{ box-shadow: var(--shadow-md); transform: translateY(-2px); border-color: var(--line-2); }
.feature .ficon{
  width: 46px; height: 46px; border-radius: 12px; background: var(--accent-soft);
  border: 1px solid var(--accent-line); display: grid; place-items: center; margin-bottom: 20px;
}
.feature .ficon svg{ width: 24px; height: 24px; stroke: var(--accent); fill: none; }
.feature h3{ font-size: 20px; margin-bottom: 9px; }
.feature p{ color: var(--ink-2); font-size: 15.5px; }

/* ============================================================ Pricing ============================================================ */
.pricing-grid{ display: grid; grid-template-columns: repeat(3, 1fr); gap: var(--gap); }
.plan{
  background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius-lg);
  padding: 32px 28px 28px; box-shadow: var(--shadow-sm); position: relative;
  display: flex; flex-direction: column;
  transition: box-shadow .2s ease, transform .2s ease;
}
.plan:hover{ box-shadow: var(--shadow-md); transform: translateY(-2px); }
.plan.is-featured{
  border-color: var(--accent-line); background: var(--accent-soft);
  box-shadow: 0 0 0 1px var(--accent-line), var(--shadow-md);
}
.plan-badge{
  position: absolute; top: -13px; left: 50%; transform: translateX(-50%);
  background: var(--accent); color: var(--accent-ink);
  font-family: var(--font-mono); font-size: 11px; font-weight: 500; letter-spacing: 0.06em; text-transform: uppercase;
  padding: 4px 14px; border-radius: 999px; white-space: nowrap;
}
.plan-name{ font-size: 14px; font-family: var(--font-mono); color: var(--ink-3); text-transform: uppercase; letter-spacing: 0.06em; font-weight: 500; }
.plan-price{ margin-top: 12px; display: flex; align-items: baseline; gap: 4px; }
.plan-price .amount{ font-size: clamp(36px, 4vw, 48px); font-weight: 600; letter-spacing: -0.03em; }
.plan-price .currency{ font-size: 20px; font-weight: 500; color: var(--ink-2); align-self: flex-start; margin-top: 8px; }
.plan-price .period{ font-size: 15px; color: var(--ink-3); margin-left: 2px; }
.plan-desc{ color: var(--ink-2); font-size: 14.5px; margin-top: 8px; }
.plan-divider{ height: 1px; background: var(--line); margin-block: 24px; }
.plan-features{ list-style: none; margin: 0; padding: 0; display: flex; flex-direction: column; gap: 10px; flex: 1; }
.plan-features li{ display: flex; align-items: flex-start; gap: 10px; font-size: 15px; color: var(--ink-2); }
.plan-features li svg{ flex: none; width: 16px; height: 16px; stroke: var(--accent); fill: none; margin-top: 3px; }
.plan .btn{ margin-top: 28px; width: 100%; }

/* ============================================================ FAQ ============================================================ */
.faq-list{ display: flex; flex-direction: column; gap: 0; border: 1px solid var(--line); border-radius: var(--radius-lg); overflow: hidden; }
.faq-item{ border-bottom: 1px solid var(--line); }
.faq-item:last-child{ border-bottom: 0; }
.faq-q{
  width: 100%; appearance: none; border: 0; background: var(--surface);
  display: flex; align-items: center; justify-content: space-between; gap: 16px;
  padding: 22px 24px; cursor: pointer; text-align: left;
  font-family: var(--font-sans); font-size: 17px; font-weight: 500; color: var(--ink);
  transition: background .14s ease;
}
.faq-q:hover{ background: var(--surface-2); }
.faq-q svg{ flex: none; width: 20px; height: 20px; stroke: var(--ink-3); fill: none; transition: transform .24s cubic-bezier(.3,.7,.4,1); }
.faq-item[open] .faq-q svg{ transform: rotate(45deg); }
.faq-a{ padding: 0 24px 22px; color: var(--ink-2); font-size: 16px; line-height: 1.65; background: var(--surface); }

/* ============================================================ CTA band ============================================================ */
.cta-band{
  background:
    radial-gradient(120% 140% at 12% 0%, oklch(0.58 0.15 266) 0%, var(--accent) 45%, var(--accent-press) 100%);
  color: var(--accent-ink); border-radius: var(--radius-lg); padding: clamp(40px, 6vw, 64px);
  position: relative; overflow: hidden;
}
.cta-band::after{
  content:""; position: absolute; inset: 0; pointer-events: none;
  background-image: repeating-linear-gradient(90deg, oklch(1 0 0 / 0.06) 0 1px, transparent 1px 56px);
  -webkit-mask-image: radial-gradient(120% 120% at 80% 50%, #000, transparent 75%);
  mask-image: radial-gradient(120% 120% at 80% 50%, #000, transparent 75%);
}
.cta-band h2{ color: var(--accent-ink); font-size: clamp(26px, 3.4vw, 40px); max-width: 18ch; position: relative; }
.cta-band p{ color: oklch(0.985 0.01 266 / 0.82); margin-top: 14px; max-width: 50ch; position: relative; }
.cta-band .btn{ --_bg: var(--surface); margin-top: 28px; position: relative; background: var(--surface); color: var(--accent-press); }
.cta-band .btn:hover{ background: oklch(0.97 0.01 266); }

/* ============================================================ Footer ============================================================ */
.site-footer{ border-top: 1px solid var(--line); background: var(--surface-2); }
.footer-grid{
  display: grid; grid-template-columns: 1.6fr repeat(3, 1fr); gap: clamp(24px, 4vw, 48px);
  padding-block: clamp(44px, 6vw, 64px);
}
.footer-brand .brand{ font-size: 19px; }
.footer-brand p{ color: var(--ink-2); font-size: 14.5px; margin-top: 14px; max-width: 34ch; }
.fcol h4{ font-size: 13px; font-family: var(--font-mono); letter-spacing: 0.06em; text-transform: uppercase; color: var(--ink-3); font-weight: 500; margin-bottom: 14px; }
.fcol a{ display: block; color: var(--ink-2); font-size: 15px; padding: 5px 0; transition: color .14s ease; }
.fcol a:hover{ color: var(--accent); }
.footer-bottom{
  border-top: 1px solid var(--line); padding-block: 22px; display: flex; align-items: center;
  justify-content: space-between; gap: 16px; flex-wrap: wrap; color: var(--ink-3); font-size: 13.5px;
}
.footer-bottom .mono{ font-size: 12.5px; }

/* ============================================================ Mobile drawer ============================================================ */
.drawer{ position: fixed; inset: 0; z-index: 60; display: none; }
.drawer[data-open="1"]{ display: block; }
.drawer-scrim{ position: absolute; inset: 0; background: oklch(0.2 0.02 266 / 0.4); -webkit-backdrop-filter: blur(2px); backdrop-filter: blur(2px); }
.drawer-panel{
  position: absolute; top: 0; right: 0; height: 100%; width: min(86vw, 340px);
  background: var(--surface); box-shadow: var(--shadow-lg); padding: 20px;
  display: flex; flex-direction: column; gap: 6px;
  animation: drawer-in .22s cubic-bezier(.3,.7,.4,1);
}
@keyframes drawer-in{ from{ transform: translateX(100%); } to{ transform: translateX(0); } }
.drawer-head{ display: flex; align-items: center; justify-content: space-between; margin-bottom: 12px; }
.drawer-panel a{ font-size: 18px; font-weight: 500; color: var(--ink); padding: 12px 10px; border-radius: 10px; display: block; }
.drawer-panel a:hover{ background: var(--surface-2); }
.drawer-panel .btn{ margin-top: 14px; }
.drawer-panel .lang{ margin-top: 18px; align-self: flex-start; }

/* ============================================================ Reveal animation ============================================================ */
.reveal{ opacity: 0; transform: translateY(14px); }
.reveal.in{ opacity: 1; transform: none; transition: opacity .6s ease, transform .6s cubic-bezier(.2,.7,.3,1); }
@media (prefers-reduced-motion: reduce){ .reveal{ opacity: 1 !important; transform: none !important; } }

/* ============================================================ Section variants ============================================================ */
.section--alt{ background: var(--surface-2); border-block: 1px solid var(--line); }

/* Mobile drawer brand */
.drawer-brand{ font-size: 18px; }

/* Download section */
.dl-row{ display: flex; flex-wrap: wrap; gap: var(--gap); align-items: flex-start; }
.dl-btn{ gap: 12px; }
.dl-coming{ display: flex; flex-direction: column; gap: 8px; padding-top: 4px; }
.dl-coming .mono{ font-size: 14px; color: var(--ink-3); }
.dl-coming span{ font-size: 14px; color: var(--ink-3); }

/* ============================================================ Responsive ============================================================ */
@media (max-width: 940px){
  .hero-grid{ grid-template-columns: 1fr; }
  .tunnel{ max-width: 520px; margin-inline: auto; order: -1; }
  .why-grid{ grid-template-columns: 1fr 1fr; }
  .pricing-grid{ grid-template-columns: 1fr; max-width: 440px; }
}
@media (max-width: 820px){
  .nav-links{ display: none; }
  .nav-right .lang{ display: none; }
  .menu-btn{ display: inline-flex; }
  .steps{ grid-template-columns: 1fr; }
  .footer-grid{ grid-template-columns: 1fr 1fr; }
}
@media (max-width: 560px){
  body{ font-size: 16px; }
  .why-grid{ grid-template-columns: 1fr; }
  .footer-grid{ grid-template-columns: 1fr; gap: 28px; }
  .hero-cta .btn{ width: 100%; }
}