.fxc-calculator {
  --fxc-panel: #ffffff;
  --fxc-card: #f8fafc;
  --fxc-border: #d6dde8;
  --fxc-text: #182230;
  --fxc-muted: #4b647d;
  --fxc-accent: #0f6cbd;
  --fxc-accent-soft: #e8f1fb;
  --fxc-positive: #0f9d58;
  --fxc-negative: #d64545;
  --fxc-shadow: 0 16px 40px rgba(15, 23, 42, 0.08);
  color: var(--fxc-text);
  font-family: "Segoe UI", Arial, sans-serif;
}

.fxc-shell {
  max-width: 1180px;
  margin: 0 auto;
  padding: 32px;
  border: 1px solid var(--fxc-border);
  border-radius: 20px;
  background: #f4f7fb;
  box-shadow: var(--fxc-shadow);
}

.fxc-header {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 24px;
  margin-bottom: 28px;
}

.fxc-eyebrow {
  margin: 0 0 8px;
  color: var(--fxc-accent);
  font-size: 0.9rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.fxc-kicker {
  margin: 0;
  font-size: clamp(1.8rem, 4vw, 2.5rem);
  font-weight: 700;
}

.fxc-subtitle {
  max-width: 620px;
  margin: 10px 0 0;
  color: var(--fxc-muted);
  font-size: 1rem;
}

.fxc-summary {
  min-width: 220px;
  padding: 16px 18px;
  border-radius: 14px;
  border: 1px solid var(--fxc-border);
  background: #ffffff;
}

.fxc-summary span,
.fxc-panel h2,
.fxc-field > span,
.fxc-output-card span {
  color: var(--fxc-muted);
}

.fxc-summary span {
  display: block;
  margin-bottom: 6px;
  font-size: 0.85rem;
  font-weight: 600;
}

.fxc-summary strong {
  font-size: 1.15rem;
  font-weight: 700;
}

.fxc-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
  gap: 24px;
}

.fxc-panel {
  padding: 24px;
  border-radius: 18px;
  border: 1px solid var(--fxc-border);
  background: var(--fxc-panel);
}

.fxc-panel h2 {
  margin: 0 0 20px;
  font-size: 1.35rem;
  font-weight: 700;
}

.fxc-form-grid,
.fxc-output-grid {
  display: grid;
  gap: 16px;
}

.fxc-form-grid {
  grid-template-columns: repeat(2, minmax(0, 1fr));
}

.fxc-field,
.fxc-output-card {
  padding: 18px;
  border-radius: 14px;
  border: 1px solid var(--fxc-border);
  background: var(--fxc-card);
}

.fxc-hidden {
  display: none;
}

.fxc-field > span,
.fxc-output-card span {
  display: block;
  margin-bottom: 10px;
  font-size: 0.88rem;
  font-weight: 600;
}

.fxc-field select,
.fxc-field input,
.fxc-toggle button {
  width: 100%;
  min-height: 54px;
  border-radius: 10px;
  border: 1px solid #c5d0dd;
  background: #ffffff;
  color: #101828;
  font: inherit;
  font-size: 1rem;
  font-weight: 500;
}

.fxc-field select,
.fxc-field input {
  padding: 0 14px;
  outline: none;
}

.fxc-field select:focus,
.fxc-field input:focus,
.fxc-toggle button:focus {
  border-color: var(--fxc-accent);
  box-shadow: 0 0 0 3px rgba(15, 108, 189, 0.12);
}

.fxc-toggle {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 10px;
}

.fxc-toggle button {
  cursor: pointer;
  transition: background 0.18s ease, border-color 0.18s ease, color 0.18s ease;
}

.fxc-toggle button.is-active {
  color: #ffffff;
  border-color: var(--fxc-accent);
  background: var(--fxc-accent);
}

.fxc-output-grid {
  grid-template-columns: repeat(2, minmax(0, 1fr));
}

.fxc-formula-box {
  margin-top: 20px;
  padding: 18px;
  border-radius: 14px;
  border: 1px solid var(--fxc-border);
  background: #f3f7fc;
}

.fxc-formula-box h3 {
  margin: 0 0 8px;
  font-size: 1rem;
}

.fxc-formula-box p {
  margin: 0 0 14px;
  color: var(--fxc-muted);
  font-size: 0.92rem;
}

.fxc-formula-list {
  display: grid;
  gap: 12px;
}

.fxc-formula-item span {
  display: block;
  margin-bottom: 6px;
  color: var(--fxc-muted);
  font-size: 0.82rem;
  font-weight: 600;
}

.fxc-formula-item code {
  display: block;
  white-space: normal;
  word-break: break-word;
  padding: 10px 12px;
  border-radius: 10px;
  background: #ffffff;
  border: 1px solid var(--fxc-border);
  font-size: 0.9rem;
  line-height: 1.5;
}

.fxc-output-card strong {
  display: block;
  font-size: clamp(1.5rem, 3vw, 2.25rem);
  font-weight: 700;
  line-height: 1.2;
}

.fxc-positive {
  color: var(--fxc-positive);
}

.fxc-negative {
  color: var(--fxc-negative);
}

@media (max-width: 980px) {
  .fxc-grid,
  .fxc-form-grid,
  .fxc-output-grid {
    grid-template-columns: 1fr;
  }

  .fxc-header {
    flex-direction: column;
    align-items: flex-start;
  }

  .fxc-summary {
    width: 100%;
  }
}

@media (max-width: 640px) {
  .fxc-shell {
    padding: 20px 16px;
  }

  .fxc-panel,
  .fxc-field,
  .fxc-output-card {
    padding: 16px;
  }

  .fxc-field select,
  .fxc-field input,
  .fxc-toggle button {
    min-height: 50px;
  }
}