:root {
  --bg-primary: #02224a;
  --bg-secondary: #043668;
  --bg-tertiary: #0a4682;
  --accent-1: #4dd5ff;
  --accent-2: #00b8e6;
  --accent-glow: rgba(77, 213, 255, 0.35);
  --text-primary: #e6f3ff;
  --text-secondary: #a8c8e6;
  --text-muted: #6b8fb5;
  --border: rgba(77, 213, 255, 0.18);
  --border-strong: rgba(77, 213, 255, 0.35);
  --card-bg: rgba(8, 56, 110, 0.5);
  --card-bg-hover: rgba(10, 70, 130, 0.7);
  --ok: #34d399;
  --bad: #ff6b81;
}
* { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }
body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "Inter", "Roboto", "Helvetica Neue", Arial, sans-serif;
  background: var(--bg-primary);
  background-image:
    radial-gradient(ellipse 80% 50% at 50% 0%, rgba(77,213,255,.18), transparent 70%),
    radial-gradient(ellipse 60% 40% at 80% 100%, rgba(0,184,230,.10), transparent 70%),
    linear-gradient(180deg, #02224a 0%, #01142e 100%);
  background-attachment: fixed;
  color: var(--text-primary);
  line-height: 1.6;
  min-height: 100vh;
  -webkit-font-smoothing: antialiased;
}
a { color: var(--accent-1); text-decoration: none; transition: color .2s ease; }
a:hover { color: var(--accent-2); }
.container { max-width: 980px; margin: 0 auto; padding: 0 24px; }

/* Header */
.header { padding: 20px 0; border-bottom: 1px solid var(--border); position: sticky; top: 0; z-index: 100; background: rgba(2,34,74,.7); backdrop-filter: blur(8px); -webkit-backdrop-filter: blur(8px); }
.header__inner { display: flex; align-items: center; justify-content: space-between; gap: 16px; }
.brand { display: flex; align-items: center; gap: 12px; font-weight: 700; font-size: 1.15rem; color: var(--text-primary); }
.brand img { width: 36px; height: 36px; border-radius: 8px; display: block; }
.brand:hover { color: var(--accent-1); }
.header__nav { display: flex; gap: 8px; flex-wrap: wrap; }
.header__nav a { padding: 8px 14px; border-radius: 8px; font-size: .92rem; font-weight: 500; color: var(--text-secondary); }
.header__nav a:hover { background: var(--card-bg); color: var(--accent-1); }

/* Hero */
.hero { text-align: center; padding: 52px 0 28px; }
.hero h1 { font-size: clamp(1.9rem, 5vw, 2.8rem); font-weight: 800; letter-spacing: -0.03em; line-height: 1.08; margin-bottom: 14px; background: linear-gradient(180deg, #fff 0%, var(--accent-1) 100%); -webkit-background-clip: text; background-clip: text; -webkit-text-fill-color: transparent; }
.hero p { color: var(--text-secondary); max-width: 560px; margin: 0 auto; font-size: 1.05rem; }
.chips { display: flex; gap: 10px; justify-content: center; flex-wrap: wrap; margin-top: 22px; }
.chip { display: inline-flex; align-items: center; gap: 7px; padding: 8px 14px; border-radius: 999px; background: var(--card-bg); border: 1px solid var(--border); font-size: .86rem; color: var(--text-secondary); }
.chip svg { width: 15px; height: 15px; color: var(--accent-1); }

/* Checkout */
.checkout { max-width: 860px; margin: 12px auto 0; }
.tariffs { display: grid; grid-template-columns: repeat(4, 1fr); gap: 14px; margin-bottom: 26px; }
@media (max-width: 760px) { .tariffs { grid-template-columns: repeat(2, 1fr); } }
@media (max-width: 420px) { .tariffs { grid-template-columns: 1fr; } }

.tariff { position: relative; cursor: pointer; display: block; }
.tariff input { position: absolute; opacity: 0; pointer-events: none; }
.tariff__inner { display: block; height: 100%; padding: 22px 18px 20px; border: 1.5px solid var(--border); border-radius: 18px; background: var(--card-bg); transition: all .2s ease; }
.tariff:hover .tariff__inner { border-color: var(--border-strong); transform: translateY(-3px); }
.tariff input:checked + .tariff__inner { border-color: var(--accent-1); box-shadow: 0 0 28px var(--accent-glow); background: var(--card-bg-hover); }
.tariff__badge { position: absolute; top: -11px; left: 50%; transform: translateX(-50%); background: linear-gradient(135deg, var(--accent-1), var(--accent-2)); color: #001428; font-size: .72rem; font-weight: 700; letter-spacing: .02em; padding: 4px 12px; border-radius: 999px; text-transform: uppercase; white-space: nowrap; box-shadow: 0 6px 18px var(--accent-glow); }
.tariff__badge--save { background: rgba(77,213,255,.18); color: var(--accent-1); border: 1px solid var(--border-strong); box-shadow: none; }
.tariff__name { font-size: .92rem; font-weight: 600; color: var(--text-secondary); text-transform: uppercase; letter-spacing: .04em; margin-bottom: 10px; }
.tariff__price { display: flex; align-items: baseline; gap: 5px; }
.tariff__amount { font-size: 2rem; font-weight: 800; letter-spacing: -0.02em; line-height: 1; color: var(--text-primary); }
.tariff__cur { font-size: 1.1rem; font-weight: 600; color: var(--text-secondary); }
.tariff__per { font-size: .84rem; color: var(--text-muted); margin-top: 6px; }
.tariff__check { position: absolute; top: 14px; right: 14px; width: 22px; height: 22px; border-radius: 50%; border: 1.5px solid var(--border-strong); display: flex; align-items: center; justify-content: center; opacity: 0; transition: .2s; }
.tariff input:checked + .tariff__inner .tariff__check { opacity: 1; background: linear-gradient(135deg, var(--accent-1), var(--accent-2)); border-color: transparent; }
.tariff__check svg { width: 12px; height: 12px; color: #001428; }

.field { margin-bottom: 16px; }
.field label { display: block; font-size: .9rem; color: var(--text-secondary); margin-bottom: 8px; }
.field input { width: 100%; padding: 14px 16px; border-radius: 12px; border: 1.5px solid var(--border); background: rgba(2,20,46,.6); color: var(--text-primary); font-size: 1rem; }
.field input::placeholder { color: var(--text-muted); }
.field input:focus { outline: none; border-color: var(--accent-1); box-shadow: 0 0 0 3px rgba(77,213,255,.12); }

.btn { display: inline-flex; align-items: center; justify-content: center; gap: 10px; padding: 15px 26px; border-radius: 12px; font-weight: 600; font-size: 1.02rem; border: none; cursor: pointer; transition: all .2s ease; text-decoration: none; width: 100%; }
.btn-primary { background: linear-gradient(135deg, var(--accent-1), var(--accent-2)); color: #001428; box-shadow: 0 8px 24px var(--accent-glow), inset 0 1px 0 rgba(255,255,255,.3); }
.btn-primary:hover { transform: translateY(-2px); color: #001428; }
.btn-primary:disabled { opacity: .6; cursor: default; transform: none; }
.btn-ghost { background: var(--card-bg); color: var(--text-primary); border: 1px solid var(--border-strong); }
.btn-ghost:hover { border-color: var(--accent-1); color: var(--accent-1); }

.reassure { display: flex; align-items: center; justify-content: center; gap: 8px; color: var(--text-muted); font-size: .88rem; margin-top: 14px; text-align: center; }
.reassure svg { width: 15px; height: 15px; color: var(--accent-1); flex-shrink: 0; }
.err { color: var(--bad); min-height: 18px; margin: 12px 0 0; text-align: center; }
.hint { color: var(--text-muted); font-size: .82rem; text-align: center; margin-top: 14px; }

/* Steps + FAQ */
.section-title { text-align: center; margin: 56px 0 28px; }
.section-title h2 { font-size: clamp(1.5rem, 4vw, 2rem); font-weight: 800; letter-spacing: -0.02em; }
.steps { display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px; }
@media (max-width: 700px) { .steps { grid-template-columns: 1fr; } }
.step { background: var(--card-bg); border: 1px solid var(--border); border-radius: 16px; padding: 24px; text-align: center; }
.step__num { width: 40px; height: 40px; border-radius: 12px; margin: 0 auto 14px; background: linear-gradient(135deg, rgba(77,213,255,.2), rgba(0,184,230,.05)); color: var(--accent-1); display: flex; align-items: center; justify-content: center; font-weight: 800; font-size: 1.1rem; }
.step h3 { font-size: 1.05rem; margin-bottom: 6px; }
.step p { color: var(--text-secondary); font-size: .92rem; }

.faq { max-width: 720px; margin: 0 auto; display: flex; flex-direction: column; gap: 12px; }
.faq details { background: var(--card-bg); border: 1px solid var(--border); border-radius: 14px; padding: 4px 20px; }
.faq summary { cursor: pointer; padding: 16px 0; font-weight: 600; list-style: none; display: flex; justify-content: space-between; align-items: center; }
.faq summary::-webkit-details-marker { display: none; }
.faq summary::after { content: "+"; color: var(--accent-1); font-size: 1.3rem; font-weight: 400; }
.faq details[open] summary::after { content: "−"; }
.faq p { color: var(--text-secondary); font-size: .94rem; padding: 0 0 16px; }

/* Footer */
.footer { padding: 48px 0 40px; margin-top: 56px; border-top: 1px solid var(--border); text-align: center; color: var(--text-muted); font-size: .9rem; }
.footer__links { margin-bottom: 12px; display: flex; gap: 22px; justify-content: center; flex-wrap: wrap; }
.footer a { color: var(--text-secondary); }
.footer a:hover { color: var(--accent-1); }

/* Success */
.card { background: var(--card-bg); border: 1px solid var(--border); border-radius: 20px; padding: clamp(28px, 5vw, 48px); text-align: center; max-width: 640px; margin: 48px auto; }
.card h1 { margin: 16px 0 8px; font-size: 1.7rem; }
.card p { color: var(--text-secondary); }
.spinner { width: 46px; height: 46px; border-radius: 50%; margin: 0 auto; border: 4px solid var(--border); border-top-color: var(--accent-1); animation: spin 1s linear infinite; }
@keyframes spin { to { transform: rotate(360deg); } }
.badge-ico { width: 60px; height: 60px; border-radius: 50%; margin: 0 auto; font-size: 32px; line-height: 60px; }
.badge-ico.ok { background: linear-gradient(135deg, var(--accent-1), var(--accent-2)); color: #001428; }
.badge-ico.bad { background: var(--bad); color: #fff; }
.sub { display: flex; gap: 8px; margin: 16px 0 8px; }
.sub input { flex: 1; padding: 13px; border-radius: 10px; border: 1.5px solid var(--border); background: rgba(2,20,46,.6); color: var(--text-primary); font-size: .85rem; }
.sub button { padding: 0 18px; border: none; border-radius: 10px; background: linear-gradient(135deg, var(--accent-1), var(--accent-2)); color: #001428; cursor: pointer; font-weight: 700; }
.howto { text-align: left; color: var(--text-secondary); line-height: 1.8; max-width: 420px; margin: 12px auto 0; }