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

:root {
  --bg: #f0fafb;
  --surface: #ffffff;
  --text: #015249;
  --muted: #268479;
  --accent: #77c9d4;
  --accent-dark: #57bc90;
  --shadow: 0 20px 40px rgba(16, 30, 70, 0.32);
}

body {
  font-family: "Inter", "Segoe UI", Roboto, Arial, sans-serif;
  color: var(--text);
  background: var(--bg);
  line-height: 1.6;
}

.container {
  width: min(95%, 1100px);
  margin: 0 auto;
  padding: 1.5rem 0;
}

.site-header {
  background: #ffffff;
  box-shadow: 0 0 15px rgba(0, 0, 0, 0.07);
  position: sticky;
  top: 0;
  z-index: 100;
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0.85rem 0;
}

.logo {
  font-weight: 800;
  font-size: 1.45rem;
  color: var(--text);
}

.logo span {
  color: var(--accent-dark);
}

.main-nav a {
  margin-left: 1.3rem;
  text-decoration: none;
  color: var(--text);
  font-weight: 600;
}

.main-nav a:hover,
.main-nav a.active {
  color: var(--accent);
}

.hero {
  background: linear-gradient(120deg, #77c9d4 0%, #57bc90 100%);
  color: #ffffff;
  padding: 5rem 0 4rem;
  text-align: center;
}

.hero h1 {
  font-size: clamp(1.8rem, 3.5vw, 2.8rem);
  margin-bottom: 1rem;
  line-height: 1.15;
}

.hero p {
  max-width: 700px;
  margin: 0.8rem auto 1.8rem;
  font-size: 1.03rem;
  color: rgba(255, 255, 255, 0.95);
}

.btn,
.btn-secondary {
  display: inline-block;
  border-radius: 0.6rem;
  padding: 0.85rem 1.5rem;
  font-weight: 700;
  border: 0;
  cursor: pointer;
  text-decoration: none;
  transition: background 0.3s ease, color 0.3s ease;
}

.card .btn {
  display: inline-block;
  margin: 1rem auto 0;
}

.btn {
  background: var(--accent-dark);
  color: #fff;
}

.btn:hover {
  background: #77c9d4;
}

.btn-secondary {
  background: var(--accent);
  color: #ffffff;
  margin-top: 1rem;
}

.btn-secondary:hover {
  background: #5fb8c8;
}

.features,
.about-preview,
.about-page,
.contact-page {
  background: var(--surface);
  margin-top: 1.2rem;
  border-radius: 1.1rem;
  box-shadow: var(--shadow);
  padding: 2rem;
}

.features h2,
.about-preview h2,
.about-page h1,
.about-page h2,
.contact-page h1 {
  margin-bottom: 0.75rem;
}

.subtitle {
  color: var(--muted);
  margin-bottom: 1rem;
}

.grid {
  display: grid;
  gap: 1.25rem;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
}

.card {
  background: #d6f0f0;
  border: 1px solid #c4e8ec;
  border-radius: 0.8rem;
  padding: 1.25rem;
  transition: box-shadow 0.3s ease;  text-align: center;}

.card:hover {
  box-shadow: 0 12px 24px rgba(109, 191, 202, 0.4);
}

.card h3 {
  margin-bottom: 0.6rem;
  color: var(--accent-dark);
}

.about-page ul {
  list-style: inside disc;
  margin-top: 0.75rem;
  color: var(--muted);
}

.contact-grid {
  display: grid;
  gap: 1rem;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
}

.contact-card {
  background: #e8f5f0;
  border: 1px solid #d0e8e2;
  border-radius: 0.8rem;
  padding: 1.25rem;
  transition: box-shadow 0.3s ease;
}

.contact-card:hover {
  box-shadow: 0 12px 24px rgba(87, 188, 144, 0.3);
}

.contact-form label {
  display: block;
  font-size: 0.95rem;
  margin-bottom: 0.35rem;
  color: #015249;
}

.contact-form input,
.contact-form textarea {
  width: 100%;
  border: 1px solid #77c9d4;
  border-radius: 0.55rem;
  padding: 0.7rem;
  margin-bottom: 0.8rem;
  font-size: 1rem;
}

.site-footer {
  margin-top: 2rem;
  padding: 1.4rem 0;
  background: #4a9b85;
  color: #e6f7f9;
  text-align: center;
}

.footer-grid {
  display: grid;
  gap: 1rem;
  grid-template-columns: repeat(auto-fit, minmax(210px, 1fr));
  text-align: center;
}

.site-footer h4,
.site-footer p,
.site-footer a {
  text-align: center;
}

.site-footer h4 {
  margin-bottom: 0.5rem;
  color: #ffffff;
}

.site-footer a {
  display: inline-block;
  color: #77c9d4;
  text-decoration: none;
  margin-bottom: 0.35rem;
}

.site-footer a:hover {
  color: #ffffff;
}

@media (max-width: 768px) {
  .header-inner {
    flex-wrap: wrap;
    gap: 0.6rem;
  }

  .main-nav {
    width: 100%;
    display: flex;
    justify-content: center;
  }

  .main-nav a {
    margin-left: 0.8rem;
    margin-right: 0.8rem;
  }

  .hero {
    padding: 3.5rem 0 2.5rem;
  }
}