:root {
  --bg-primary: #faf8f5; /* Soft oatmeal cream */
  --bg-secondary: #ffffff; /* Softer warm white */
  --bg-card: rgba(133, 88, 56, 0.02); /* Very soft sienna tint */
  --bg-card-hover: rgba(133, 88, 56, 0.05);
  --text-primary: #231714; /* Deep espresso brown */
  --text-secondary: #614e47; /* Cocoa brown */
  --text-muted: #9e8c84; /* Soft taupe */
  --brand: #ba3c2a; /* Warm coffee-house red */
  --brand-glow: rgba(186, 60, 42, 0.12);
  --accent: #855838; /* Warm sienna */
  --accent-glow: rgba(133, 88, 56, 0.1);
  --success: #2e7d32; /* Rich leaf green */
  --success-glow: rgba(46, 125, 50, 0.12);
  --danger: #c62828;
  --border: rgba(35, 23, 20, 0.08); /* Soft brown border */
  --border-focus: rgba(133, 88, 56, 0.4);
  --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
}

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

html, body {
  overflow-x: hidden;
  max-width: 100%;
}

body {
  background-color: var(--bg-primary);
  color: var(--text-primary);
  font-family: var(--font-sans);
  min-height: 100vh;
  line-height: 1.6;
  position: relative;
}

/* Background glowing warm ambient lighting */
body::before, body::after {
  content: '';
  position: absolute;
  width: 50vw;
  height: 50vw;
  border-radius: 50%;
  z-index: -1;
  filter: blur(160px);
  opacity: 0.04;
  pointer-events: none;
}
body::before {
  top: 0;
  right: -10vw;
  background: var(--brand);
}
body::after {
  bottom: 0;
  left: -10vw;
  background: var(--accent);
}

header {
  border-bottom: 1px solid var(--border);
  backdrop-filter: blur(12px);
  background: rgba(250, 248, 245, 0.85);
  position: sticky;
  top: 0;
  z-index: 100;
  transition: all 0.3s ease;
}

.nav-container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 1.25rem 2rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.logo {
  font-size: 1.75rem;
  font-weight: 600;
  letter-spacing: -0.03em;
  background: linear-gradient(135deg, var(--text-primary) 30%, var(--brand) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  text-decoration: none;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.logo-dot {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--brand);
  display: inline-block;
  animation: pulse-dot 2.5s infinite;
}

@keyframes pulse-dot {
  0% { transform: scale(0.95); opacity: 0.7; }
  50% { transform: scale(1.15); opacity: 1; }
  100% { transform: scale(0.95); opacity: 0.7; }
}

.nav-links {
  display: flex;
  gap: 2rem;
  align-items: center;
}

.nav-link {
  color: var(--text-secondary);
  text-decoration: none;
  font-weight: 500;
  font-size: 0.95rem;
  transition: color 0.2s ease;
}

.nav-link:hover {
  color: var(--text-primary);
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.75rem 1.5rem;
  border-radius: 4px; /* Squarer, architectural edges */
  font-weight: 500;
  font-size: 0.95rem;
  text-decoration: none;
  transition: all 0.2s cubic-bezier(0.4, 0, 0.2, 1);
  cursor: pointer;
  border: none;
  gap: 0.5rem;
}

.btn-primary {
  background: var(--brand);
  color: white;
  box-shadow: 0 2px 8px var(--brand-glow);
}

.btn-primary:hover {
  transform: translateY(-1px);
  box-shadow: 0 4px 12px rgba(186, 60, 42, 0.3);
  background: #c84633;
}

.btn-secondary {
  background: rgba(35, 23, 20, 0.03);
  color: var(--text-primary);
  border: 1px solid var(--border);
}

.btn-secondary:hover {
  background: rgba(35, 23, 20, 0.06);
  transform: translateY(-1px);
}

.btn-accent {
  background: var(--accent);
  color: white;
  box-shadow: 0 2px 8px var(--accent-glow);
}

.btn-accent:hover {
  transform: translateY(-1px);
  background: #946440;
  box-shadow: 0 4px 12px rgba(133, 88, 56, 0.3);
}

/* Hero Section */
.hero {
  max-width: 1200px;
  margin: 0 auto;
  padding: 5rem 2rem 3rem;
  text-align: center;
  display: flex;
  flex-direction: column;
  align-items: center;
}

.badge {
  background: rgba(133, 88, 56, 0.06);
  border: 1px solid rgba(133, 88, 56, 0.15);
  color: var(--accent);
  padding: 0.4rem 0.9rem;
  border-radius: 4px; /* Squarer architectural edges */
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  margin-bottom: 2rem;
  display: inline-block;
  backdrop-filter: blur(4px);
}

.hero h1 {
  font-size: clamp(2.2rem, 4.5vw, 3.5rem);
  font-weight: 600; /* Less bold, elegant */
  line-height: 1.2;
  letter-spacing: -0.03em;
  max-width: 900px;
  margin-bottom: 1.5rem;
}

.hero h1 span {
  background: linear-gradient(135deg, var(--brand) 30%, var(--accent) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.hero p {
  color: var(--text-secondary);
  font-size: clamp(1.05rem, 1.8vw, 1.2rem);
  max-width: 720px;
  margin-bottom: 2.5rem;
  font-weight: 400;
}

.cta-group {
  display: flex;
  gap: 1rem;
  margin-bottom: 4rem;
}

/* Calculator Styles */
.calculator-container {
  width: 100%;
  max-width: 900px;
  background: var(--bg-secondary);
  border: 1px solid var(--border);
  border-radius: 8px; /* Squarer, architectural edges */
  padding: 3rem;
  margin: 4rem auto;
  box-shadow: 0 8px 32px rgba(35, 23, 20, 0.04);
}

.calc-title {
  font-size: 1.75rem;
  font-weight: 600; /* Less bold */
  letter-spacing: -0.02em;
  margin-bottom: 2rem;
  text-align: center;
}

.calc-grid {
  display: grid;
  grid-template-columns: 1.2fr 1fr;
  gap: 3rem;
}

.calc-inputs {
  display: flex;
  flex-direction: column;
  gap: 2rem;
}

.input-header {
  display: flex;
  justify-content: space-between;
  margin-bottom: 0.75rem;
  font-weight: 500;
  font-size: 0.95rem;
}

.input-label {
  color: var(--text-secondary);
}

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

.range-slider {
  -webkit-appearance: none;
  width: 100%;
  height: 4px;
  border-radius: 2px;
  background: rgba(35, 23, 20, 0.08);
  outline: none;
}

.range-slider::-webkit-slider-thumb {
  -webkit-appearance: none;
  appearance: none;
  width: 18px;
  height: 18px;
  border-radius: 50%;
  background: var(--accent);
  cursor: pointer;
  box-shadow: 0 1px 4px rgba(0,0,0,0.15);
  transition: transform 0.1s ease;
}

.range-slider::-webkit-slider-thumb:hover {
  transform: scale(1.1);
}

.calc-outputs {
  background: rgba(133, 88, 56, 0.02);
  border: 1px solid var(--border);
  border-radius: 6px;
  padding: 2rem;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  text-align: center;
  position: relative;
  overflow: hidden;
}

.calc-outputs::before {
  content: '';
  position: absolute;
  top: -50%;
  left: -50%;
  width: 200%;
  height: 200%;
  background: radial-gradient(circle, rgba(133, 88, 56, 0.03) 0%, rgba(0,0,0,0) 70%);
  pointer-events: none;
}

.output-label {
  color: var(--text-secondary);
  font-size: 0.85rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: 0.5rem;
}

.savings-amount {
  font-size: clamp(2.2rem, 3.5vw, 3rem);
  font-weight: 600;
  color: var(--brand);
  margin: 0.5rem 0;
  letter-spacing: -0.03em;
}

.calc-breakdown {
  width: 100%;
  margin-top: 1.5rem;
  border-top: 1px solid var(--border);
  padding-top: 1.5rem;
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
  font-size: 0.9rem;
}

.breakdown-row {
  display: flex;
  justify-content: space-between;
}

.breakdown-label {
  color: var(--text-muted);
}

.breakdown-value {
  font-weight: 500;
}

.breakdown-value.danger {
  color: var(--brand);
}

.breakdown-value.success {
  color: var(--success);
}

/* Feature Grid */
.features {
  max-width: 1200px;
  margin: 0 auto;
  padding: 4rem 2rem;
}

.section-title {
  text-align: center;
  font-size: 2rem;
  font-weight: 600;
  letter-spacing: -0.03em;
  margin-bottom: 3rem;
}

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

.card {
  background: var(--bg-secondary);
  border: 1px solid var(--border);
  border-radius: 8px; /* Squarer, architectural edges */
  padding: 2.5rem;
  transition: all 0.25s ease;
  display: flex;
  flex-direction: column;
  height: 100%;
}

.card:hover {
  border-color: var(--accent);
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(35, 23, 20, 0.03);
}

.card-icon {
  width: 48px;
  height: 48px;
  border-radius: 4px; /* Squarer */
  background: rgba(133, 88, 56, 0.05);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 1.5rem;
  font-size: 1.5rem;
  color: var(--accent);
  border: 1px solid var(--border);
}

.card h3 {
  font-size: 1.35rem;
  font-weight: 600;
  margin-bottom: 1rem;
  letter-spacing: -0.01em;
}

.card p {
  color: var(--text-secondary);
  font-size: 0.95rem;
  line-height: 1.6;
}

/* Footer styling */
footer {
  border-top: 1px solid var(--border);
  padding: 4rem 2rem;
  background: rgba(35, 23, 20, 0.02);
  margin-top: 6rem;
}

.footer-content {
  max-width: 1200px;
  margin: 0 auto;
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 2rem;
}

.footer-text {
  color: var(--text-muted);
  font-size: 0.9rem;
}

/* Interactive form demo */
.demo-section {
  max-width: 550px;
  width: 100%;
  background: var(--bg-secondary);
  border: 1px solid var(--border);
  border-radius: 8px; /* Squarer */
  padding: 2.5rem;
  box-shadow: 0 8px 32px rgba(35, 23, 20, 0.03);
  margin: 3rem auto 5rem;
}

.demo-title {
  font-size: 1.75rem;
  font-weight: 600;
  margin-bottom: 1.5rem;
  text-align: center;
}

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

.form-label {
  display: block;
  font-size: 0.8rem;
  font-weight: 600;
  margin-bottom: 0.5rem;
  color: var(--text-secondary);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.form-input {
  width: 100%;
  background: var(--bg-secondary);
  border: 1px solid var(--border);
  color: var(--text-primary);
  padding: 0.85rem 1.1rem;
  border-radius: 4px; /* Squarer */
  font-family: inherit;
  font-size: 0.95rem;
  transition: all 0.15s ease;
}

.form-input:focus {
  outline: none;
  border-color: var(--accent);
  box-shadow: 0 0 0 3px rgba(133, 88, 56, 0.15);
}

@media (max-width: 768px) {
  .nav-links .nav-link {
    display: none;
  }
  .nav-container {
    padding: 1rem;
  }
  .nav-links {
    gap: 0.5rem;
  }
  .hero {
    padding: 3rem 1rem 2rem;
  }
  .features {
    padding: 3rem 1rem;
  }
  .grid {
    grid-template-columns: 1fr;
    gap: 1.5rem;
  }
  .cta-group {
    flex-direction: column;
    width: 100%;
    max-width: 320px;
  }
  .btn {
    width: 100%;
  }
  .calc-grid {
    grid-template-columns: 1fr;
    gap: 2rem;
  }
  .calculator-container {
    padding: 2rem 1.5rem;
  }
  .preview-device-mockup {
    padding: 1rem;
  }
}