/* Tokens mirror tailwind.config.ts in protocolink-landing-page */
:root {
  --gray-100: #fbfbfb;
  --gray-200: #eaeaea;
  --gray-400: #999999;
  --gray-600: #666666;
  --gray-800: #333333;
  --gray-900: #191919;
  --blue-300: #99c5fa;
  --blue-500: #338cf5;
  --blue-600: #0070f4;
  --blue-700: #0064da;
  --teal-400: #4fd1c5;
  --white: #ffffff;
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.04), 0 4px 6px -2px rgba(0, 0, 0, 0.02);
  --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.12), 0 10px 10px -5px rgba(0, 0, 0, 0.02);
  --shadow: 0 1px 3px 0 rgba(0, 0, 0, 0.12), 0 1px 2px 0 rgba(0, 0, 0, 0.03);
}

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

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  background: var(--white);
  color: var(--gray-900);
  font-family: Inter, system-ui, sans-serif;
  letter-spacing: -0.01em;
  line-height: 1.5;
  -webkit-font-smoothing: antialiased;
}

img {
  max-width: 100%;
  height: auto;
}

a {
  color: inherit;
}

.wrap {
  max-width: 72rem;
  margin: 0 auto;
  padding: 0 1rem;
}

.wrap-wide {
  max-width: 80rem;
}

.h2 {
  font-size: 2rem;
  font-weight: 800;
  line-height: 1.25;
  letter-spacing: -0.02em;
  margin: 0 0 1rem;
}

.lead {
  font-size: 1.25rem;
  color: var(--gray-600);
  margin: 0;
}

.section-head {
  max-width: 56rem;
  margin: 0 auto;
  padding-bottom: 3rem;
  text-align: center;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.75rem 2rem;
  border-radius: 0.25rem;
  background: var(--blue-600);
  color: var(--white);
  font-weight: 500;
  line-height: 1.375;
  text-decoration: none;
  box-shadow: var(--shadow-lg);
  transition: background-color 0.15s ease-in-out;
}

.btn:hover {
  background: var(--blue-700);
}

/* Vertical connector line between sections (original design detail) */
.connector {
  position: relative;
}

.connector::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  margin: 0 auto;
  width: 2px;
  height: 5rem;
  background: var(--gray-200);
  transform: translateY(-50%);
}

/* ---------- Announcement + Header ---------- */
.topbar {
  position: sticky;
  top: 0;
  z-index: 30;
  background: rgba(255, 255, 255, 0.9);
  backdrop-filter: blur(4px);
  -webkit-backdrop-filter: blur(4px);
  box-shadow: var(--shadow-lg);
}

.announce {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: center;
  gap: 4px 16px;
  padding: 10px 1rem;
  background: var(--gray-900);
  color: var(--white);
  font-size: 0.9375rem;
  text-align: center;
}

.announce a {
  font-weight: 600;
  color: var(--white);
  text-underline-offset: 3px;
}

.header .wrap {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 4rem;
}

.logo {
  display: block;
  line-height: 0;
}

.logo img {
  height: 32px;
  width: auto;
}

.btn-sm {
  display: inline-flex;
  align-items: center;
  padding: 0.5rem 1rem;
  border-radius: 0.25rem;
  background: var(--gray-900);
  color: var(--white);
  font-size: 0.9375rem;
  font-weight: 500;
  text-decoration: none;
  box-shadow: var(--shadow);
  transition: background-color 0.15s ease-in-out;
}

.btn-sm:hover {
  background: var(--gray-800);
}

/* ---------- Hero ---------- */
.hero {
  padding: 5rem 0 3rem;
  text-align: center;
}

.hero h1 {
  font-size: 3.25rem;
  font-weight: 800;
  line-height: 1.125;
  letter-spacing: -0.02em;
  margin: 0 0 2.5rem;
}

.gradient-text {
  background: linear-gradient(to right, var(--blue-500), var(--teal-400));
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

.hero .lead {
  max-width: 48rem;
  margin: 0 auto 3.5rem;
}

/* ---------- Capabilities (6 cards, light/dark split background) ---------- */
.capabilities {
  background: linear-gradient(to bottom, var(--gray-100) 0, var(--gray-100) 55%, var(--gray-900) 55%, var(--gray-900) 100%);
  padding: 3rem 0 4rem;
}

.cards {
  max-width: 24rem;
  margin: 0 auto;
  display: grid;
  gap: 1.5rem;
}

.card {
  display: flex;
  flex-direction: column;
  align-items: center;
  padding: 1.5rem;
  border-radius: 0.25rem;
  background: var(--white);
  box-shadow: var(--shadow-xl);
  text-align: center;
}

.card svg {
  width: 4rem;
  height: 4rem;
  padding: 0.25rem;
  margin: -0.25rem 0 0.5rem;
}

.card h3 {
  font-size: 1.25rem;
  font-weight: 700;
  line-height: 1.375;
  margin: 0 0 0.25rem;
}

.card p {
  margin: 0;
  color: var(--gray-600);
}

.ic-bg {
  fill: var(--blue-600);
}

.ic-a {
  stroke: var(--white);
}

.ic-b {
  stroke: var(--blue-300);
}

/* ---------- How we build (3 static steps) ---------- */
.how {
  padding: 3rem 0;
}

.steps {
  display: grid;
  gap: 2.5rem;
}

.step {
  display: grid;
  gap: 1.25rem;
  align-items: center;
}

.step-text {
  padding: 1.25rem;
  border-radius: 0.25rem;
  background: var(--gray-200);
  font-size: 1.125rem;
}

.step-text strong {
  display: block;
  line-height: 1.375;
  margin-bottom: 0.25rem;
}

.step-text span {
  color: var(--gray-600);
}

.step img {
  display: block;
  width: 100%;
  border-radius: 0.25rem;
}

/* ---------- Logos ---------- */
.ecosystem .wrap > div {
  padding: 3rem 0;
  border-top: 1px solid var(--gray-200);
}

.logo-grid {
  max-width: 24rem;
  margin: 0 auto;
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 0.5rem;
  padding: 0;
  list-style: none;
}

.logo-grid + .section-head {
  padding-top: 5rem;
}

.logo-grid li {
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 0.5rem 0;
}

.logo-grid img {
  width: 60px;
  height: 60px;
  object-fit: cover;
  border-radius: 9999px;
}

/* ---------- FAQ ---------- */
.faq {
  padding: 3rem 0;
}

.faq-list {
  max-width: 48rem;
  margin: 0 auto;
}

.faq details {
  border-bottom: 1px solid var(--gray-200);
}

.faq details:first-child {
  border-top: 1px solid var(--gray-200);
}

.faq summary {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding: 1.25rem 0;
  font-size: 1.125rem;
  font-weight: 700;
  cursor: pointer;
  list-style: none;
}

.faq summary::-webkit-details-marker {
  display: none;
}

.faq summary::after {
  content: '+';
  flex: none;
  width: 2rem;
  height: 2rem;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 9999px;
  background: var(--white);
  box-shadow: var(--shadow);
  font-weight: 400;
}

.faq details[open] summary::after {
  content: '\2212';
}

.faq .answer {
  padding: 0 0 1.25rem;
  color: var(--gray-600);
}

.faq .answer p {
  margin: 0 0 0.75rem;
}

.faq .answer a {
  color: var(--blue-600);
}

/* ---------- Contact CTA ---------- */
.contact {
  background: var(--gray-900);
  color: var(--white);
  text-align: center;
  padding: 4rem 0;
}

.contact .lead {
  color: var(--gray-400);
  margin-bottom: 2.5rem;
}

/* ---------- Footer ---------- */
.footer .wrap {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding-top: 2rem;
  padding-bottom: 2rem;
}

.footer p {
  margin: 0;
  font-size: 0.875rem;
  color: var(--gray-600);
}

.footer p a {
  color: var(--gray-600);
}

.footer p a:hover {
  color: var(--gray-900);
}

/* ---------- Breakpoints (Tailwind: sm 640, md 768, lg 1024) ---------- */
@media (min-width: 640px) {
  .wrap {
    padding: 0 1.5rem;
  }
}

@media (min-width: 768px) {
  .h2 {
    font-size: 2.625rem;
  }

  .header .wrap {
    height: 5rem;
  }

  .hero {
    padding: 7rem 0 5rem;
  }

  .hero h1 {
    font-size: 5.5rem;
  }

  .section-head {
    padding-bottom: 4rem;
  }

  .capabilities,
  .how,
  .faq {
    padding: 5rem 0;
  }

  .ecosystem .wrap > div {
    padding: 5rem 0;
  }

  .cards {
    max-width: 42rem;
    grid-template-columns: repeat(2, 1fr);
  }

  .step {
    grid-template-columns: 5fr 7fr;
    gap: 2rem;
  }

  .step:nth-child(even) .step-text {
    order: 2;
  }

  .logo-grid {
    max-width: 56rem;
    grid-template-columns: repeat(9, 1fr);
  }

  .logo-grid + .section-head {
    padding-top: 7rem;
  }

  .contact {
    padding: 6rem 0;
  }
}

@media (min-width: 1024px) {
  .cards {
    max-width: none;
    grid-template-columns: repeat(3, 1fr);
  }

  .capabilities {
    background: linear-gradient(to bottom, var(--gray-100) 0, var(--gray-100) 60%, var(--gray-900) 60%, var(--gray-900) 100%);
  }
}