/* GST Calculator - #3d85c6 brand */
:root {
  --gst-brand: #3d85c6;
  --gst-brand-dark: #2c6396;
  --gst-brand-light: #eaf4fb;
  --gst-brand-border: #b6d5f2;
  --gst-bg: #f4f8fc;
  --gst-surface: rgba(255, 255, 255, 0.88);
  --gst-solid: #ffffff;
  --gst-text: #1a1a1a;
  --gst-muted: #64748b;
  --gst-shadow: 0 14px 40px rgba(61, 133, 198, 0.16);
  --gst-radius: 18px;
  --gst-font: 'DM Sans', system-ui, sans-serif;
}

#tool-main {
  font-family: var(--gst-font);
  color: var(--gst-text);
  background: var(--gst-bg);
  background-image:
    radial-gradient(ellipse 80% 50% at 10% -10%, rgba(61, 133, 198, 0.14), transparent),
    radial-gradient(ellipse 50% 40% at 100% 0%, rgba(91, 163, 224, 0.1), transparent);
  padding-bottom: 32px;
}

.gst-wrap {
  max-width: 520px;
  margin: 0 auto;
  padding: 16px;
}

.gst-hero {
  text-align: center;
  margin-bottom: 20px;
}

.gst-hero h1 {
  font-size: clamp(1.5rem, 4vw, 2rem);
  font-weight: 800;
  color: var(--gst-brand);
  margin: 0 0 8px;
}

.gst-hero p {
  color: var(--gst-muted);
  font-size: 0.92rem;
  margin: 0 auto;
  max-width: 400px;
}

.gst-glass {
  background: var(--gst-surface);
  backdrop-filter: blur(12px);
  border: 1px solid var(--gst-brand-border);
  border-radius: var(--gst-radius);
  box-shadow: var(--gst-shadow);
  padding: 20px;
}

.gst-field {
  margin-bottom: 16px;
}

.gst-field label {
  display: block;
  font-size: 0.82rem;
  font-weight: 600;
  color: var(--gst-brand-dark);
  margin-bottom: 6px;
}

.gst-amount-wrap {
  position: relative;
}

.gst-amount-wrap .gst-currency {
  position: absolute;
  left: 14px;
  top: 50%;
  transform: translateY(-50%);
  font-weight: 700;
  color: var(--gst-brand);
}

.gst-amount-wrap input {
  width: 100%;
  padding: 14px 14px 14px 36px;
  font-size: 1.25rem;
  font-weight: 600;
  border: 1.5px solid var(--gst-brand-border);
  border-radius: 12px;
  background: #f7fbff;
  box-sizing: border-box;
}

.gst-amount-wrap input:focus {
  border-color: var(--gst-brand);
  outline: none;
  box-shadow: 0 0 0 3px var(--gst-brand-light);
}

.gst-rate-chips {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-bottom: 16px;
}

.gst-rate-chips button {
  padding: 8px 14px;
  border-radius: 999px;
  border: 1px solid var(--gst-brand-border);
  background: var(--gst-solid);
  font-size: 0.82rem;
  font-weight: 700;
  color: var(--gst-brand-dark);
  cursor: pointer;
  transition: all 0.15s;
}

.gst-rate-chips button:hover {
  border-color: var(--gst-brand);
  background: var(--gst-brand-light);
}

.gst-rate-chips button.active {
  background: var(--gst-brand);
  border-color: var(--gst-brand);
  color: #fff;
}

.gst-select {
  width: 100%;
  padding: 10px 12px;
  border-radius: 10px;
  border: 1.5px solid var(--gst-brand-border);
  font-size: 0.95rem;
  background: #f7fbff;
}

.gst-mode-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 10px;
  margin-bottom: 14px;
}

.gst-pill {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  padding: 12px 10px;
  border: 1.5px solid var(--gst-brand-border);
  border-radius: 12px;
  cursor: pointer;
  font-size: 0.8rem;
  font-weight: 600;
  text-align: center;
  background: var(--gst-solid);
  transition: all 0.15s;
}

.gst-pill:has(input:checked) {
  border-color: var(--gst-brand);
  background: var(--gst-brand-light);
  color: var(--gst-brand-dark);
}

.gst-pill input {
  accent-color: var(--gst-brand);
}

.gst-supply {
  margin-bottom: 16px;
}

.gst-supply legend {
  font-size: 0.82rem;
  font-weight: 600;
  color: var(--gst-brand-dark);
  margin-bottom: 8px;
}

.gst-supply-options {
  display: flex;
  gap: 16px;
  font-size: 0.85rem;
}

.gst-supply-options label {
  display: flex;
  align-items: center;
  gap: 6px;
  cursor: pointer;
}

.gst-actions {
  display: flex;
  gap: 10px;
}

.gst-btn {
  flex: 1;
  padding: 13px 16px;
  border-radius: 12px;
  font-weight: 700;
  font-size: 0.95rem;
  border: none;
  cursor: pointer;
  transition: transform 0.15s, background 0.2s;
}

.gst-btn--primary {
  background: var(--gst-brand);
  color: #fff;
  box-shadow: 0 6px 18px rgba(61, 133, 198, 0.35);
}

.gst-btn--primary:hover {
  background: var(--gst-brand-dark);
  transform: translateY(-1px);
}

.gst-btn--ghost {
  background: var(--gst-solid);
  border: 1px solid var(--gst-brand-border);
  color: var(--gst-text);
  flex: 0 0 auto;
  padding-left: 18px;
  padding-right: 18px;
}

.gst-hint {
  text-align: center;
  font-size: 0.72rem;
  color: var(--gst-muted);
  margin-top: 10px;
}

.gst-result {
  margin-top: 18px;
  padding: 18px;
  border: 1px solid rgba(61, 133, 198, 0.35);
  border-radius: var(--gst-radius);
  background: linear-gradient(180deg, #f7fbff 0%, #fff 100%);
  animation: gstIn 0.35s ease;
}

@keyframes gstIn {
  from { opacity: 0; transform: translateY(8px); }
  to { opacity: 1; transform: translateY(0); }
}

.gst-result[hidden] { display: none !important; }

.gst-result-total {
  text-align: center;
  margin-bottom: 16px;
  padding-bottom: 14px;
  border-bottom: 1px dashed var(--gst-brand-border);
}

.gst-result-total span {
  display: block;
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--gst-muted);
}

.gst-result-total strong {
  font-size: 1.75rem;
  color: var(--gst-brand);
  font-weight: 800;
}

.gst-stat-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 10px;
  margin-bottom: 14px;
}

.gst-stat {
  padding: 12px;
  border-radius: 10px;
  background: var(--gst-brand-light);
  text-align: center;
}

.gst-stat label {
  display: block;
  font-size: 0.68rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--gst-muted);
  margin-bottom: 4px;
}

.gst-stat strong {
  font-size: 1rem;
  color: var(--gst-brand-dark);
}

.gst-breakdown {
  padding: 12px;
  border-radius: 10px;
  background: #fff;
  border: 1px solid var(--gst-brand-border);
  font-size: 0.88rem;
}

.gst-breakdown h3 {
  font-size: 0.8rem;
  margin: 0 0 8px;
  color: var(--gst-brand);
}

.gst-breakdown p {
  margin: 4px 0;
  display: flex;
  justify-content: space-between;
}

.gst-mode-note {
  font-size: 0.78rem;
  color: var(--gst-muted);
  text-align: center;
  margin: 12px 0 0;
}

.gst-result-actions {
  display: flex;
  gap: 10px;
  margin-top: 14px;
}

.gst-result-actions .gst-btn {
  flex: 1;
}

.gst-related {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 10px;
  margin-top: 14px;
}

.gst-related a {
  padding: 12px;
  text-decoration: none;
  color: inherit;
  font-size: 0.85rem;
  border-radius: 12px;
  border: 1px solid var(--gst-brand-border);
  background: var(--gst-surface);
}

.gst-related a strong {
  display: block;
  color: var(--gst-brand);
}

.gst-related a span {
  font-size: 0.72rem;
  color: var(--gst-muted);
}

.gst-seo {
  margin-top: 24px;
  padding: 20px;
}

.gst-seo p { color: var(--gst-muted); font-size: 0.9rem; line-height: 1.6; }

.gst-faq details {
  margin-bottom: 8px;
  padding: 12px;
  border: 1px solid var(--gst-brand-border);
  border-radius: 10px;
  background: var(--gst-solid);
}

.gst-faq summary { font-weight: 600; cursor: pointer; color: var(--gst-brand-dark); }

#toastContainer {
  position: fixed;
  bottom: 20px;
  right: 16px;
  z-index: 10001;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.gst-toast {
  padding: 11px 14px;
  border-radius: 10px;
  background: #fff;
  border: 1px solid var(--gst-brand-border);
  box-shadow: var(--gst-shadow);
  font-size: 0.85rem;
  opacity: 0;
  transform: translateY(8px);
  transition: all 0.25s;
}

.gst-toast.is-visible {
  opacity: 1;
  transform: translateY(0);
}

.gst-toast--success { border-left: 4px solid #10b981; }
.gst-toast--error { border-left: 4px solid #ef4444; }
.gst-toast--warning { border-left: 4px solid #f59e0b; }