/* Black-Scholes Option Pricing */

:root {
  --primary: #0369a1;
  --primary-light: #0ea5e9;
  --surface: #ffffff;
  --surface-alt: #f0f9ff;
  --on-surface: #0c4a6e;
  --on-surface-secondary: #64748b;
  --radius-lg: 12px;
  --radius-md: 8px;
  --shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
}

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

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  background: linear-gradient(135deg, #e0f2fe 0%, #bae6fd 100%);
  min-height: 100vh;
  color: var(--on-surface);
}

.app-container {
  max-width: 800px;
  margin: 0 auto;
  padding: 20px;
}

header {
  text-align: center;
  margin-bottom: 32px;
}

header h1 {
  font-size: 2rem;
  color: var(--primary);
  margin-bottom: 4px;
}

.subtitle {
  color: var(--on-surface-secondary);
  font-size: 0.9rem;
}

main {
  display: flex;
  flex-direction: column;
  gap: 24px;
}

/* Params */
.params-section, .results-section, .Greeks-section, .chart-section {
  background: var(--surface);
  border-radius: var(--radius-lg);
  padding: 24px;
  box-shadow: var(--shadow);
}

.params-section h2, .results-section h2, .Greeks-section h2, .chart-section h2 {
  margin-bottom: 20px;
  color: var(--primary);
}

.param-group {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.param-group label {
  font-weight: 500;
  font-size: 0.9rem;
}

.params-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 20px;
}

/* Results */
.results-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
  gap: 16px;
}

.result-card {
  background: var(--surface-alt);
  border-radius: var(--radius-md);
  padding: 16px;
  text-align: center;
}

.result-value {
  font-size: 1.75rem;
  font-weight: bold;
  color: var(--primary);
}

.result-label {
  font-size: 0.8rem;
  color: var(--on-surface-secondary);
}

/* Greeks */
.Greeks-section h2 {
  margin-bottom: 16px;
}

.greeks-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(120px, 1fr));
  gap: 12px;
}

.greek-item {
  display: flex;
  justify-content: space-between;
  padding: 12px;
  background: var(--surface-alt);
  border-radius: var(--radius-md);
}

.greek-name {
  font-weight: 500;
}

.greek-value {
  font-weight: 600;
  color: var(--primary);
}

/* Chart */
.chart-section {
  margin-top: 16px;
}

.chart-section canvas {
  width: 100%;
  height: 300px;
}