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

:root {
  --navy: #0F1B2D; --navy2: #152033; --navy3: #1C2D42; --navy4: #243348;
  --teal: #00C9A7; --teal-dim: rgba(0,201,167,0.12);
  --off-white: #F0F4F8; --muted: #8899AA; --dimmer: #556070;
  --divider: rgba(255,255,255,0.07);
  --mono: 'JetBrains Mono', monospace; --sans: 'Space Grotesk', sans-serif;
  --radius: 12px;
}

html { font-size: 16px; scroll-behavior: smooth; }
body { background: var(--navy); color: var(--off-white); font-family: var(--sans); min-height: 100vh; display: flex; flex-direction: column; -webkit-font-smoothing: antialiased; }
a { color: inherit; }

header {
  padding: 1rem 2rem; display: flex; align-items: center; justify-content: space-between;
  border-bottom: 1px solid var(--divider); position: sticky; top: 0;
  background: rgba(15,27,45,0.96); backdrop-filter: blur(12px); z-index: 100;
}
.logo { display: flex; align-items: center; gap: 0.55rem; text-decoration: none; }
.logo-mark { width: 30px; height: 30px; background: var(--teal); border-radius: 7px; display: grid; place-items: center; font-family: var(--mono); font-size: 0.7rem; font-weight: 700; color: var(--navy); }
.logo-text { font-size: 1.05rem; font-weight: 600; letter-spacing: -0.02em; }
.logo-text span { color: var(--teal); }
.header-right { display: flex; align-items: center; gap: 1rem; }
.header-right a { color: var(--muted); text-decoration: none; font-size: 0.85rem; font-weight: 500; transition: color 0.15s; }
.header-right a:hover { color: var(--off-white); }

.btn { border: none; border-radius: 8px; font-family: var(--sans); font-weight: 600; cursor: pointer; transition: opacity 0.15s, transform 0.1s; display: inline-flex; align-items: center; gap: 0.4rem; white-space: nowrap; text-decoration: none; }
.btn:hover { opacity: 0.85; }
.btn:active { transform: scale(0.97); }
.btn-primary { background: var(--teal); color: var(--navy); padding: 0.45rem 1rem; font-size: 0.85rem; }
.btn-ghost { background: var(--navy3); color: var(--off-white); padding: 0.45rem 0.9rem; font-size: 0.82rem; border: 1px solid var(--divider); }
.btn-sm { padding: 0.3rem 0.75rem; font-size: 0.78rem; border-radius: 6px; }

.breadcrumb { max-width: 760px; margin: 0 auto; width: 100%; padding: 1rem 2rem 0; font-size: 0.78rem; color: var(--dimmer); }
.breadcrumb a { color: var(--dimmer); text-decoration: none; }
.breadcrumb a:hover { color: var(--muted); }
.breadcrumb span[aria-current] { color: var(--muted); }

.hero { text-align: center; padding: 2rem 1.5rem 1.75rem; }
.hero-eyebrow { font-family: var(--mono); font-size: 0.72rem; color: var(--teal); letter-spacing: 0.14em; text-transform: uppercase; margin-bottom: 0.9rem; }
.hero h1 { font-size: clamp(1.6rem, 4vw, 2.6rem); font-weight: 700; letter-spacing: -0.035em; line-height: 1.15; margin-bottom: 0.75rem; }
.hero h1 em { font-style: normal; color: var(--teal); }
.hero p { color: var(--muted); font-size: 0.97rem; max-width: 560px; margin: 0 auto; line-height: 1.6; }

main { max-width: 760px; margin: 0 auto; width: 100%; padding: 0 2rem; flex: 1; }

.calc-card { background: var(--navy2); border: 1px solid var(--divider); border-radius: var(--radius); padding: 1.5rem; margin: 1.5rem 0 2rem; }
.calc-title { font-size: 0.95rem; font-weight: 700; margin-bottom: 1rem; }
.calc-note { font-size: 0.76rem; color: var(--dimmer); margin-top: 0.9rem; line-height: 1.5; }

.seo-block { margin-bottom: 1.75rem; }
.seo-block h2 { font-size: 1rem; font-weight: 700; letter-spacing: -0.02em; margin-bottom: 0.6rem; }
.seo-block p { font-size: 0.875rem; color: var(--muted); line-height: 1.7; }
.seo-block p + p { margin-top: 0.6rem; }

.related-links { display: flex; flex-wrap: wrap; gap: 0.6rem; margin: 0 0 2.5rem; }
.related-links a {
  font-size: 0.8rem; color: var(--muted); text-decoration: none;
  border: 1px solid var(--divider); border-radius: 20px; padding: 0.4rem 0.9rem;
  transition: color 0.15s, border-color 0.15s;
}
.related-links a:hover { color: var(--teal); border-color: var(--teal); }

.faq-section { border-top: 1px solid var(--divider); padding: 2.5rem 0 3rem; }
.faq-eyebrow { font-family: var(--mono); font-size: 0.7rem; color: var(--teal); letter-spacing: 0.14em; text-transform: uppercase; margin-bottom: 0.75rem; font-weight: 500; }
.faq-heading { font-size: 1.35rem; font-weight: 700; letter-spacing: -0.025em; margin-bottom: 1.5rem; }
.faq-list { display: flex; flex-direction: column; }
.faq-item { border-top: 1px solid var(--divider); }
.faq-item:last-child { border-bottom: 1px solid var(--divider); }
.faq-question { width: 100%; background: none; border: none; text-align: left; padding: 1.1rem 0; font-family: var(--sans); font-size: 0.95rem; font-weight: 600; color: var(--off-white); cursor: pointer; display: flex; align-items: center; justify-content: space-between; gap: 1rem; transition: color 0.15s; }
.faq-question:hover { color: var(--teal); }
.faq-chevron { font-size: 0.7rem; color: var(--dimmer); flex-shrink: 0; transition: transform 0.2s ease, color 0.15s; }
.faq-item.open .faq-chevron { transform: rotate(180deg); color: var(--teal); }
.faq-answer { font-size: 0.875rem; color: var(--muted); line-height: 1.65; max-height: 0; overflow: hidden; transition: max-height 0.25s ease, padding 0.2s ease; padding: 0; }
.faq-item.open .faq-answer { max-height: 300px; padding-bottom: 1.1rem; }

.modal-backdrop {
  position: fixed;
  inset: 0;
  background: rgba(5,12,22,0.85);
  backdrop-filter: blur(6px);
  z-index: 300;
  display: none;
  align-items: center;
  justify-content: center;
  padding: 1rem;
}

.modal-backdrop.open { display: flex; }

.modal {
  background: var(--navy2);
  border: 1px solid rgba(0,201,167,0.2);
  border-radius: 16px;
  width: 100%;
  max-width: 480px;
  max-height: 88vh;
  display: flex;
  flex-direction: column;
  box-shadow: 0 24px 64px rgba(0,0,0,0.6);
}

.modal-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1.1rem 1.35rem;
  border-bottom: 1px solid var(--divider);
}

.modal-title {
  font-size: 1rem;
  font-weight: 700;
  letter-spacing: -0.02em;
}

.modal-close {
  background: var(--navy3);
  border: 1px solid var(--divider);
  color: var(--muted);
  border-radius: 7px;
  width: 30px; height: 30px;
  font-size: 1rem;
  cursor: pointer;
  display: grid;
  place-items: center;
  transition: color 0.15s;
}

.modal-close:hover { color: var(--off-white); }

.modal-body {
  flex: 1;
  overflow-y: auto;
  padding: 1.1rem 1.35rem;
}

footer {
  border-top: 1px solid var(--divider);
  padding: 1rem 2rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.footer-note { font-size: 0.74rem; color: var(--dimmer); }

.footer-links { display: flex; gap: 1.25rem; flex-wrap: wrap; }

.footer-links a {
  font-size: 0.74rem;
  color: var(--dimmer);
  text-decoration: none;
  transition: color 0.15s;
}

.footer-links a:hover { color: var(--muted); }

.footer-link-btn {
  background: none;
  border: none;
  font-family: var(--sans);
  font-size: 0.74rem;
  color: var(--dimmer);
  cursor: pointer;
  padding: 0;
  transition: color 0.15s;
}

.footer-link-btn:hover { color: var(--muted); }

@media (max-width: 720px) {
  header { padding: 0.8rem 1rem; }
  .breadcrumb { padding: 1rem 1rem 0; }
  main { padding: 0 1rem; }
  .hero { padding: 1.5rem 1rem 1.25rem; }
  .hero h1 { font-size: 1.5rem; }
  footer { padding: 0.85rem 1rem; }
}