:root {
  --accent-color: #007bff;
  --accent-light: #e6f2ff;
}

body {
  margin: 0;
  font-family: 'Inter', sans-serif;
  background: linear-gradient(to bottom, #ffffff, #f4faff);
  color: #333;
  display: flex;
  flex-direction: column;
  min-height: 100vh;
}
.header {
  position: sticky;
  top: 0;
  z-index: 1000;
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 1rem 2rem;
  background: white;
  box-shadow: 0 2px 4px rgba(0,0,0,0.1);
}
.logo {
  font-size: 1.5rem;
  font-weight: bold;
  color: var(--accent-color);
}
nav ul {
  list-style: none;
  display: flex;
  gap: 1.5rem;
}
nav ul li a {
  text-decoration: none;
  color: #333;
  font-weight: 500;
  transition: color 0.2s ease;
}

nav ul li a:hover {
  color: var(--accent-color);
}
.hero {
  padding: 5rem 2rem 3rem;
  text-align: center;
}
.hero h1 {
  font-size: 2.5rem;
  color: var(--accent-color);
  margin-bottom: 0.5rem;
}
.hero p {
  margin-top: 0;
  font-size: 1.2rem;
  color: #555;
}
.hero .search {
  padding: 1rem;
  font-size: 1rem;
  width: 80%;
  max-width: 500px;
  border-radius: 10px;
  border: 1px solid #ccc;
  margin-top: 1rem;
}
.hero .cta {
  display: inline-block;
  margin-top: 1.5rem;
  padding: 0.75rem 2rem;
  background: var(--accent-color);
  color: #fff;
  border-radius: 8px;
  text-decoration: none;
  transition: background 0.2s ease;
}
.hero .cta:hover {
  background: #0056b3;
}
.category-sections {
  padding: 2rem;
}
.category-sections h2 {
  text-align: center;
  margin-top: 2rem;
  color: var(--accent-color);
}
.calculator-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 1.5rem;
  padding: 1rem;
  max-width: 1000px;
  margin: auto;
}
.card {
  background: white;
  padding: 1.5rem;
  border-radius: 10px;
  text-align: center;
  text-decoration: none;
  color: #000;
  font-weight: 600;
  box-shadow: 0 4px 10px rgba(0,0,0,0.1);
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}
.card:hover {
  transform: translateY(-5px);
  box-shadow: 0 6px 14px rgba(0,0,0,0.1);
  background: var(--accent-light);
}
.footer {
  margin-top: auto;
  padding: 2rem;
  background: rgba(0,0,0,0.05);
  text-align: center;
  font-size: 0.9rem;
}
.footer a {
  color: var(--accent-color);
  text-decoration: none;
}
.footer a:hover {
  text-decoration: underline;
}
/* Generic styles for all calculator pages */
main, section.calculator-section {
  max-width: 600px;
  margin: 2rem auto;
  padding: 2rem;
  background: white;
  border-radius: 10px;
  box-shadow: 0 4px 10px rgba(0,0,0,0.1);
}
form label {
  display: block;
  margin-top: 1em;
  font-weight: 600;
}
form input:not(.search),
form select {
  width: 100%;
  padding: 0.75rem;
  margin-top: 0.5rem;
  border: 1px solid #ccc;
  border-radius: 8px;
}
button {
  margin-top: 1.5rem;
  padding: 0.75rem 2rem;
  background: var(--accent-color);
  color: #fff;
  border: none;
  border-radius: 8px;
  cursor: pointer;
  transition: background 0.2s ease;
}
button:hover {
  background: #0056b3;
}
#result {
  margin-top: 1.5rem;
  font-weight: bold;
  color: var(--accent-color);
}