:root {
  --sust-primary: #10B981; /* Premium Emerald Green */
  --sust-primary-dark: #059669;
  --sust-secondary: #3B82F6; /* Ocean Blue */
  --sust-bg-color: #F8FAFC;
  --sust-card-bg: rgba(255, 255, 255, 0.85);
  --sust-text-main: #1E293B;
  --sust-text-muted: #64748B;
  --sust-border: #E2E8F0;
  --sust-radius: 16px;
  --sust-shadow: 0 10px 25px -5px rgba(0, 0, 0, 0.05), 0 8px 10px -6px rgba(0, 0, 0, 0.01);
  --sust-font: 'Inter', system-ui, -apple-system, sans-serif;
}

.sust-calc-wrapper {
  max-width: 800px;
  margin: 2rem auto;
  font-family: var(--sust-font);
  color: var(--sust-text-main);
  background: linear-gradient(135deg, #f0fdf4 0%, #eff6ff 100%);
  padding: 2rem;
  border-radius: var(--sust-radius);
  box-shadow: var(--sust-shadow);
  box-sizing: border-box;
}

.sust-calc-wrapper * {
  box-sizing: border-box;
}

.sust-calc-header {
  text-align: center;
  margin-bottom: 2rem;
}

.sust-calc-title {
  margin: 0 0 0.5rem 0;
  font-size: 2rem;
  font-weight: 800;
  background: linear-gradient(to right, var(--sust-primary), var(--sust-secondary));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.sust-calc-desc {
  color: var(--sust-text-muted);
  font-size: 1rem;
  margin: 0;
}

.sust-calc-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 2rem;
}

@media (min-width: 640px) {
  .sust-calc-grid {
    grid-template-columns: 1fr 1fr;
  }
}

.sust-input-group {
  margin-bottom: 1.25rem;
  position: relative;
}

.sust-input-group label {
  display: block;
  font-weight: 600;
  margin-bottom: 0.5rem;
  font-size: 0.9rem;
  color: var(--sust-text-main);
}

.sust-input,
.sust-select {
  width: 100%;
  padding: 0.75rem 1rem;
  border: 1px solid var(--sust-border);
  border-radius: 8px;
  font-size: 1rem;
  background: rgba(255,255,255,0.9);
  transition: all 0.3s ease;
  color: var(--sust-text-main);
  font-family: inherit;
}

.sust-input:focus,
.sust-select:focus {
  outline: none;
  border-color: var(--sust-primary);
  box-shadow: 0 0 0 3px rgba(16, 185, 129, 0.2);
}

.sust-btn-wrapper {
  grid-column: 1 / -1;
  text-align: center;
  margin-top: 1rem;
}

.sust-btn {
  background: linear-gradient(135deg, var(--sust-primary), var(--sust-primary-dark));
  color: white;
  border: none;
  padding: 0.85rem 2rem;
  font-size: 1.1rem;
  font-weight: 600;
  border-radius: 50px;
  cursor: pointer;
  transition: transform 0.2s ease, box-shadow 0.2s ease;
  box-shadow: 0 4px 6px -1px rgba(16, 185, 129, 0.4);
}

.sust-btn:hover {
  transform: translateY(-2px);
  box-shadow: 0 10px 15px -3px rgba(16, 185, 129, 0.4);
}

.sust-results-card {
  grid-column: 1 / -1;
  background: var(--sust-card-bg);
  backdrop-filter: blur(10px);
  border: 1px solid var(--sust-border);
  border-radius: 12px;
  padding: 2rem;
  margin-top: 1rem;
  display: none;
  animation: slideUp 0.5s ease-out forwards;
}

.sust-results-card.active {
  display: block;
}

.sust-result-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
  gap: 1.5rem;
}

.sust-result-item {
  text-align: center;
  padding: 1rem;
  background: rgba(255,255,255,0.6);
  border-radius: 12px;
  border: 1px solid rgba(226, 232, 240, 0.5);
}

.sust-result-val {
  display: block;
  font-size: 1.75rem;
  font-weight: 800;
  color: var(--sust-primary);
  margin-bottom: 0.25rem;
}

.sust-result-label {
  font-size: 0.85rem;
  color: var(--sust-text-muted);
  font-weight: 500;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

@keyframes slideUp {
  from { opacity: 0; transform: translateY(20px); }
  to { opacity: 1; transform: translateY(0); }
}

.sust-input-flex {
  display: flex;
  align-items: center;
}

.sust-input-prefix {
  background: var(--sust-bg-color);
  border: 1px solid var(--sust-border);
  border-right: none;
  padding: 0.75rem 1rem;
  border-radius: 8px 0 0 8px;
  color: var(--sust-text-muted);
}
.sust-input-with-prefix {
  border-radius: 0 8px 8px 0;
}