:root {
  --bg-color: #0b0d10;
  --surface-color: rgba(30, 33, 40, 0.7);
  --border-color: rgba(255, 255, 255, 0.1);
  --text-primary: #f1f5f9;
  --text-secondary: #94a3b8;
  --accent-color: #f59e0b;
  --accent-hover: #fbbf24;
  --accent-glow: rgba(245, 158, 11, 0.2);
  --danger-color: #ef4444;
  --success-color: #10b981;
}

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
  font-family: 'Inter', 'Roboto', sans-serif;
}

body {
  background-color: var(--bg-color);
  color: var(--text-primary);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  overflow-x: hidden;
  background-image: 
    radial-gradient(circle at 15% 50%, var(--accent-glow), transparent 25%),
    radial-gradient(circle at 85% 30%, rgba(59, 130, 246, 0.1), transparent 25%);
}

header {
  background: rgba(11, 13, 16, 0.8);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border-color);
  position: sticky;
  top: 0;
  z-index: 100;
}

.nav-container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 1rem 2rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.logo {
  font-size: 1.5rem;
  font-weight: 800;
  color: var(--text-primary);
  text-decoration: none;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

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

.nav-links {
  list-style: none;
  display: flex;
  gap: 2rem;
}

.nav-links a {
  color: var(--text-secondary);
  text-decoration: none;
  font-weight: 500;
  transition: color 0.3s ease;
  position: relative;
}

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

.nav-links a::after {
  content: '';
  position: absolute;
  width: 0;
  height: 2px;
  bottom: -4px;
  left: 0;
  background-color: var(--accent-color);
  transition: width 0.3s ease;
}

.nav-links a:hover::after, .nav-links a.active::after {
  width: 100%;
}

main {
  flex: 1;
  max-width: 1200px;
  margin: 0 auto;
  padding: 4rem 2rem;
  width: 100%;
}

.hero {
  text-align: center;
  padding: 4rem 0;
}

.hero h1 {
  font-size: 3.5rem;
  margin-bottom: 1.5rem;
  background: linear-gradient(to right, #fff, var(--accent-color));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.hero p {
  font-size: 1.2rem;
  color: var(--text-secondary);
  max-width: 600px;
  margin: 0 auto 2rem;
}

.glass-panel {
  background: var(--surface-color);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border: 1px solid var(--border-color);
  border-radius: 16px;
  padding: 2rem;
  box-shadow: 0 8px 32px 0 rgba(0, 0, 0, 0.3);
  transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.glass-panel:hover {
  transform: translateY(-5px);
  box-shadow: 0 12px 40px 0 var(--accent-glow);
}

.btn {
  display: inline-block;
  padding: 0.8rem 1.5rem;
  border-radius: 8px;
  text-decoration: none;
  font-weight: 600;
  transition: all 0.3s ease;
  cursor: pointer;
  border: none;
}

.btn-primary {
  background-color: var(--accent-color);
  color: #000;
}

.btn-primary:hover {
  background-color: var(--accent-hover);
  box-shadow: 0 0 15px var(--accent-glow);
}

.grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 2rem;
  margin-top: 2rem;
}

/* Calculator Styles */
.calculator-container {
  max-width: 600px;
  margin: 0 auto;
}

.form-group {
  margin-bottom: 1.5rem;
}

.form-group label {
  display: block;
  margin-bottom: 0.5rem;
  color: var(--text-secondary);
}

.form-control {
  width: 100%;
  padding: 0.8rem 1rem;
  background: rgba(0, 0, 0, 0.2);
  border: 1px solid var(--border-color);
  border-radius: 8px;
  color: var(--text-primary);
  font-size: 1rem;
  outline: none;
  transition: border-color 0.3s ease;
}

.form-control:focus {
  border-color: var(--accent-color);
}

.result-box {
  margin-top: 2rem;
  padding: 1.5rem;
  background: rgba(0, 0, 0, 0.3);
  border-radius: 8px;
  border-left: 4px solid var(--accent-color);
}

.result-box h3 {
  margin-bottom: 0.5rem;
}

.result-value {
  font-size: 2rem;
  font-weight: bold;
}

.text-success { color: var(--success-color); }
.text-danger { color: var(--danger-color); }

footer {
  border-top: 1px solid var(--border-color);
  padding: 2rem;
  text-align: center;
  color: var(--text-secondary);
  background: rgba(11, 13, 16, 0.8);
}