/* Base Reset & Variables */
:root {
  --bg-color: #f8f9fa;
  --text-color: #212529;
  --primary-color: #2563eb;
  --primary-hover: #1d4ed8;
  --container-width: 1000px;
}

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

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

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

/* Navbar */
.navbar {
  background: #ffffff;
  border-bottom: 1px solid #e5e7eb;
  padding: 1rem 0;
}

.navbar .container {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.brand {
  font-weight: 700;
  font-size: 1.25rem;
  color: var(--text-color);
  text-decoration: none;
}

.nav-links {
  display: flex;
  list-style: none;
  gap: 1.5rem;
}

.nav-links a {
  text-decoration: none;
  color: #4b5563;
  transition: color 0.2s;
}

.nav-links a:hover {
  color: var(--primary-color);
}

/* Hero Section */
.hero {
  padding: 4rem 0;
  text-align: center;
}

.btn {
  margin-top: 1.5rem;
  padding: 0.75rem 1.5rem;
  font-size: 1rem;
  color: #fff;
  background-color: var(--primary-color);
  border: none;
  border-radius: 6px;
  cursor: pointer;
  transition: background 0.2s;
}

.btn:hover {
  background-color: var(--primary-hover);
}

.output-text {
  margin-top: 1rem;
  font-weight: 600;
  color: #10b981;
}