:root {
  --slate: #334155;
  --slate-dark: #1e293b;
  --white: #ffffff;
  --teal: #0d9488;
  --teal-hover: #0f766e;
  --gray-light: #f1f5f9;
  --gray-mid: #94a3b8;
  --gray-border: #e2e8f0;
  --font: "DM Sans", system-ui, -apple-system, sans-serif;
  --max-width: 1120px;
}

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

html {
  font-size: 16px;
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: var(--font);
  color: var(--slate);
  background: var(--white);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 1.5rem;
}

/* ------------------------------------------------
   Header
   ------------------------------------------------ */
.site-header {
  border-bottom: 1px solid var(--gray-border);
  padding: 1.25rem 0;
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.wordmark {
  font-size: 1.35rem;
  font-weight: 700;
  color: var(--slate-dark);
  text-decoration: none;
  letter-spacing: -0.02em;
}

.wordmark span {
  color: var(--teal);
}

.header-link {
  font-size: 0.9rem;
  font-weight: 500;
  color: var(--teal);
  text-decoration: none;
  transition: color 0.15s;
}

.header-link:hover {
  color: var(--teal-hover);
}

/* ------------------------------------------------
   Hero
   ------------------------------------------------ */
.hero {
  padding: 6rem 0 5rem;
  text-align: center;
  background: var(--gray-light);
}

.hero h1 {
  font-size: clamp(2rem, 5vw, 3.25rem);
  font-weight: 700;
  line-height: 1.15;
  letter-spacing: -0.03em;
  color: var(--slate-dark);
  max-width: 720px;
  margin: 0 auto 1.25rem;
}

.hero-sub {
  font-size: clamp(1rem, 2.5vw, 1.2rem);
  color: var(--gray-mid);
  max-width: 600px;
  margin: 0 auto 2.5rem;
  line-height: 1.65;
}

/* ------------------------------------------------
   Buttons
   ------------------------------------------------ */
.btn {
  display: inline-block;
  text-decoration: none;
  font-family: var(--font);
  font-weight: 600;
  border-radius: 6px;
  transition: background 0.15s, transform 0.1s;
}

.btn-primary {
  background: var(--teal);
  color: var(--white);
  padding: 0.85rem 2rem;
  font-size: 1rem;
}

.btn-primary:hover {
  background: var(--teal-hover);
  transform: translateY(-1px);
}

/* ------------------------------------------------
   The Problem
   ------------------------------------------------ */
.problem {
  padding: 5rem 0;
}

.problem h2,
.features h2,
.institutions h2 {
  font-size: clamp(1.5rem, 3.5vw, 2rem);
  font-weight: 700;
  letter-spacing: -0.02em;
  color: var(--slate-dark);
  text-align: center;
  margin-bottom: 3rem;
}

.stats-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.5rem;
  margin-bottom: 2.5rem;
}

.stat-card {
  text-align: center;
  padding: 2.25rem 1.5rem;
  border: 1px solid var(--gray-border);
  border-radius: 10px;
  background: var(--white);
}

.stat-number {
  display: block;
  font-size: clamp(1.75rem, 4vw, 2.5rem);
  font-weight: 700;
  color: var(--teal);
  letter-spacing: -0.02em;
  margin-bottom: 0.5rem;
}

.stat-label {
  display: block;
  font-size: 0.95rem;
  color: var(--gray-mid);
  line-height: 1.5;
}

.problem-text {
  max-width: 720px;
  margin: 0 auto;
  text-align: center;
  font-size: 1.05rem;
  color: var(--slate);
  line-height: 1.7;
}

/* ------------------------------------------------
   Features
   ------------------------------------------------ */
.features {
  padding: 5rem 0;
  background: var(--gray-light);
}

.features-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 1.5rem;
}

.feature-card {
  background: var(--white);
  border: 1px solid var(--gray-border);
  border-radius: 10px;
  padding: 2.25rem 2rem;
}

.feature-card h3 {
  font-size: 1.15rem;
  font-weight: 600;
  color: var(--slate-dark);
  margin-bottom: 0.6rem;
  letter-spacing: -0.01em;
}

.feature-card p {
  font-size: 0.95rem;
  color: var(--gray-mid);
  line-height: 1.6;
}

/* ------------------------------------------------
   Built for Institutions
   ------------------------------------------------ */
.institutions {
  padding: 5rem 0;
  text-align: center;
}

.institutions-text {
  max-width: 680px;
  margin: 0 auto 2.5rem;
  font-size: 1.1rem;
  line-height: 1.7;
  color: var(--slate);
}

/* ------------------------------------------------
   Footer
   ------------------------------------------------ */
.site-footer {
  border-top: 1px solid var(--gray-border);
  padding: 2rem 0;
  text-align: center;
}

.site-footer p {
  font-size: 0.85rem;
  color: var(--gray-mid);
}

.site-footer a {
  color: var(--teal);
  text-decoration: none;
}

.site-footer a:hover {
  color: var(--teal-hover);
}

/* ------------------------------------------------
   Responsive
   ------------------------------------------------ */
@media (max-width: 768px) {
  .hero {
    padding: 4rem 0 3.5rem;
  }

  .stats-grid {
    grid-template-columns: 1fr;
    gap: 1rem;
  }

  .features-grid {
    grid-template-columns: 1fr;
    gap: 1rem;
  }

  .problem,
  .features,
  .institutions {
    padding: 3.5rem 0;
  }
}

@media (max-width: 480px) {
  .hero {
    padding: 3rem 0 2.5rem;
  }

  .btn-primary {
    padding: 0.75rem 1.5rem;
    font-size: 0.95rem;
  }
}