.refract-calc-container {
  font-family: inherit; /* Inherits Astra font */
  width: 100%;
  max-width: 48rem; /* Equivalent to max-w-3xl */
  margin: 0 auto;
  border-radius: 1rem;
  border: 1px solid #e2e8f0;
  background-color: #ffffff;
  overflow: hidden;
  box-sizing: border-box;
  color: #1e293b;
}

.refract-calc-container * { box-sizing: border-box; }

.refract-header {
  background-color: #1e293b;
  color: #ffffff;
  padding: 1.5rem 2rem;
  display: flex;
  align-items: center;
  gap: 1rem;
  position: relative;
  border-bottom: 1px solid #334155;
}

.refract-header-icon {
  background-color: #334155;
  color: #60a5fa;
  padding: 0.75rem;
  border-radius: 0.75rem;
  display: flex;
}

.refract-header-text h2 {
  margin: 0 0 0.25rem 0 !important;
  font-size: 1.5rem !important;
  font-weight: 600;
  line-height: 1.2;
  color: #fff !important;
  border: none !important;
  padding: 0 !important;
}

.refract-header-text p {
  margin: 0 !important;
  color: #cbd5e1 !important;
  font-size: 0.875rem;
}

.refract-unit-toggle {
  position: absolute;
  top: 1.5rem;
  right: 1.5rem;
  display: flex;
  background-color: #334155;
  padding: 0.25rem;
  border-radius: 0.5rem;
}

.refract-unit-toggle .unit-btn {
  background: transparent;
  border: none;
  color: #cbd5e1;
  padding: 0.375rem 0.75rem;
  font-size: 0.75rem;
  font-weight: 500;
  border-radius: 0.375rem;
  cursor: pointer;
  transition: all 0.2s;
  font-family: inherit;
}

.refract-unit-toggle .unit-btn:hover { color: #fff; }
.refract-unit-toggle .unit-btn.active {
  background-color: #2563eb;
  color: #fff;
  box-shadow: 0 1px 2px rgba(0,0,0,0.1);
}

.refract-tabs {
  display: flex;
  border-bottom: 1px solid #e2e8f0;
}

.refract-tabs .tab-btn {
  flex: 1;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 1rem;
  background: transparent;
  border: none;
  border-bottom: 2px solid transparent;
  font-size: 0.875rem;
  font-weight: 500;
  color: #64748b;
  cursor: pointer;
  transition: all 0.2s;
  font-family: inherit;
}

.refract-tabs .tab-btn:hover { color: #334155; background-color: #f8fafc; }
.refract-tabs .tab-btn.active { color: #2563eb; border-bottom-color: #2563eb; background-color: #eff6ff; }

.refract-body { padding: 1.5rem 2rem; display: flex; flex-direction: column; gap: 2rem; }
.form-group { margin-bottom: 1.5rem; }

.form-group label {
  display: block; font-size: 0.875rem; font-weight: 500;
  color: #334155; margin-bottom: 0.5rem;
}

.required { color: #ef4444; }

.input-group {
  display: flex; border: 1px solid #e2e8f0; border-radius: 0.5rem;
  overflow: hidden; box-shadow: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
}

.input-group:focus-within { border-color: #3b82f6; box-shadow: 0 0 0 1px #3b82f6; }

.input-group input {
  flex: 1; width: 100%; padding: 0.625rem 1rem; border: none !important;
  background: transparent; font-size: 1rem; color: #1e293b;
  font-family: inherit; box-shadow: none !important;
}
.input-group input:focus { outline: none; }

.input-group select {
  border: none !important; border-left: 1px solid #e2e8f0 !important;
  background-color: #f8fafc !important; padding: 0.625rem 1rem !important;
  font-weight: 500; color: #475569 !important; cursor: pointer;
  outline: none; font-size: 1rem; box-shadow: none !important; border-radius: 0 !important;
}

.input-addon {
  border-left: 1px solid #e2e8f0; background-color: #f8fafc;
  padding: 0.625rem 1rem; font-weight: 500; color: #475569;
  display: flex; align-items: center; justify-content: center; min-width: 64px;
}

.form-group-calib { background-color: #f8fafc; }
.help-text { font-size: 0.75rem; color: #64748b; margin-top: 0.25rem; }

.advanced-section { padding-top: 1rem; border-top: 1px solid #f1f5f9; }
.wcf-toggle {
  display: flex; align-items: center; gap: 0.5rem; cursor: pointer;
  font-size: 0.875rem; font-weight: 500; color: #334155;
}

.wcf-input {
  margin-top: 0.75rem; margin-left: 0.5rem; padding-left: 1.5rem;
  border-left: 2px solid #e2e8f0;
}

.wcf-input label { display: block; font-size: 0.75rem; font-weight: 500; color: #475569; margin-bottom: 0.25rem; }
.wcf-input input {
  width: 100%; max-width: 150px; padding: 0.5rem 0.75rem;
  border: 1px solid #e2e8f0; border-radius: 0.5rem; font-size: 0.875rem; font-family: inherit;
}

.calc-actions { padding-top: 0.5rem; }
.reset-btn {
  display: flex; width: 100%; align-items: center; justify-content: center;
  background-color: #f1f5f9; color: #475569; border: none; padding: 0.625rem 1rem;
  border-radius: 0.5rem; font-weight: 500; cursor: pointer; transition: background-color 0.2s;
  font-family: inherit; font-size: 1rem;
}
.reset-btn:hover { background-color: #e2e8f0; }

.refract-results {
  background-color: #f8fafc; border: 1px solid #e2e8f0;
  border-radius: 0.75rem; padding: 1.5rem;
}

.result-empty { text-align: center; padding: 2rem 0; }
.result-empty-icon {
  display: inline-flex; align-items: center; justify-content: center;
  width: 4rem; height: 4rem; background-color: #f1f5f9; color: #94a3b8;
  border-radius: 50%; margin-bottom: 1rem;
}

.result-empty h3 {
  color: #1e293b !important; font-weight: 500;
  margin: 0 0 0.5rem 0 !important; border: none !important; font-size: 1.125rem !important;
}

.result-empty p { color: #64748b; font-size: 0.875rem; margin: 0 auto !important; max-width: 250px; }

.result-data h3 {
  font-size: 0.875rem !important; font-weight: 600; color: #94a3b8 !important;
  text-transform: uppercase; letter-spacing: 0.05em; margin: 0 0 0.75rem 0 !important;
  border: none !important; padding: 0 !important;
}

.res-card {
  background-color: #ffffff; padding: 1.25rem; border-radius: 0.75rem;
  box-shadow: 0 1px 2px 0 rgba(0,0,0,0.05); border: 1px solid #e2e8f0;
  border-left-width: 4px; margin-bottom: 1rem;
}

.res-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 1rem; }
.res-grid .res-card { margin-bottom: 0; }
.blue-card { border-left-color: #3b82f6; }
.green-card { border-left-color: #10b981; }
.purple-card { border-left-color: #a855f7; }

.res-label {
  display: block; font-size: 0.75rem; font-weight: 500; color: #64748b;
  text-transform: uppercase; letter-spacing: 0.05em; margin-bottom: 0.25rem;
}

.res-value { font-size: 2.25rem; font-weight: 600; color: #1e293b; line-height: 1; }
.res-grid .res-value { font-size: 1.5rem; }
.purple-card .res-value { color: #7e22ce; }
.res-unit { font-size: 0.875rem; color: #94a3b8; margin-left: 0.25rem; font-weight: 500; }

.res-actions { display: flex; gap: 0.5rem; margin-top: 1.5rem; }
.res-btn {
  display: flex; align-items: center; justify-content: center; gap: 0.5rem;
  padding: 0.625rem 1rem; border-radius: 0.5rem; font-weight: 500;
  font-size: 1rem; cursor: pointer; transition: all 0.2s; font-family: inherit;
}

.outline-btn { flex: 1; background-color: #ffffff; border: 1px solid #e2e8f0; color: #334155; }
.outline-btn:hover { background-color: #f8fafc; border-color: #cbd5e1; }
.solid-btn { flex: 2; background-color: #2563eb; border: 1px solid #2563eb; color: #ffffff; }
.solid-btn:hover { background-color: #1d4ed8; border-color: #1d4ed8; }

@media print {
  .refract-calc-container { border: none; box-shadow: none; max-width: 100%; }
  .refract-header-icon, .refract-unit-toggle, .refract-tabs, .refract-form, .res-actions { display: none !important; }
  .refract-header { background: #fff; color: #000; border-bottom: 2px solid #ccc; padding: 0 0 1rem 0; }
  .refract-header-text h2 { color: #000 !important; }
  .refract-header-text p { color: #444 !important; }
  .refract-results { background: transparent; border: none; padding: 1rem 0; }
  .res-card { break-inside: avoid; border: 1px solid #ccc; box-shadow: none; }
}

@media (max-width: 640px) {
  .refract-header { padding: 1.25rem 1.5rem; flex-wrap: wrap; }
  .refract-unit-toggle { position: relative; top: 0; right: 0; margin-top: 1rem; width: 100%; justify-content: space-between; }
  .refract-unit-toggle .unit-btn { flex: 1; text-align: center; }
  .refract-body { padding: 1.5rem; }
  .res-grid { grid-template-columns: 1fr; }
}