* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: Arial, sans-serif;
  background: #0d1117;
  color: #e6edf3;
  line-height: 1.6;
}

a {
  color: #58a6ff;
  text-decoration: none;
}

nav {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 24px 8%;
}

nav a {
  margin-left: 18px;
  color: #e6edf3;
}

.hero {
  min-height: 85vh;
  background: radial-gradient(circle at top, #1f6feb55, transparent 40%),
              linear-gradient(135deg, #0d1117, #161b22);
}

.hero-content {
  padding: 120px 8%;
  max-width: 850px;
}

.hero h1 {
  font-size: 3rem;
  margin-bottom: 16px;
}

.hero p {
  font-size: 1.2rem;
  color: #c9d1d9;
}

.button {
  display: inline-block;
  margin-top: 18px;
  padding: 12px 18px;
  background: #238636;
  color: white;
  border-radius: 8px;
  font-weight: bold;
}

.button.secondary {
  background: #1f6feb;
}

.section {
  padding: 70px 8%;
  max-width: 1000px;
  margin: auto;
}

.card {
  background: #161b22;
  border: 1px solid #30363d;
  border-radius: 14px;
  padding: 28px;
  margin-top: 24px;
  box-shadow: 0 10px 30px #00000033;
}

.card h3 {
  margin-top: 0;
  color: #ffffff;
}

.tag {
  color: #8b949e;
  font-size: 0.95rem;
}

.placeholder {
  opacity: 0.65;
  border-style: dashed;
}

footer {
  text-align: center;
  padding: 30px;
  background: #010409;
  color: #8b949e;
}

@media (max-width: 700px) {
  nav {
    flex-direction: column;
    gap: 12px;
  }

  nav a {
    margin: 0 8px;
  }

  .hero h1 {
    font-size: 2.2rem;
  }
}