/* ========== Calculator Layout ========== */
.page-header-simple {
  margin-bottom: 28px;
}
.page-header-desc {
  color: var(--color-text-muted);
  margin-top: 8px;
  font-size: 15px;
}

.calc-wrapper {
  margin-bottom: 40px;
}

.calc-panels {
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  align-items: stretch;
  gap: 16px;
  margin-bottom: 24px;
}

.calc-arrow {
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--color-accent);
  opacity: 0.6;
  padding: 0 8px;
}

.calc-panel {
  background: var(--color-bg-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-xl);
  padding: 28px;
  position: relative;
  overflow: hidden;
  box-shadow: var(--shadow-card);
}

.calc-panel::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
}

.calc-panel-old::before {
  background: linear-gradient(90deg, var(--color-accent-secondary), var(--color-accent));
}

.calc-panel-new::before {
  background: linear-gradient(90deg, var(--color-accent), var(--color-accent-warning));
}

.calc-panel-header {
  display: flex;
  align-items: center;
  gap: 14px;
  margin-bottom: 24px;
}
.calc-panel-header h3 {
  font-size: 18px;
  font-weight: 700;
  color: var(--color-text-primary);
}

.calc-panel-badge {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 6px 14px;
  border-radius: 999px;
  font-size: 13px;
  font-weight: 700;
}

.badge-old {
  background: linear-gradient(135deg, var(--color-accent-secondary), #5d8a9a);
  color: #fff;
}

.badge-new {
  background: linear-gradient(135deg, var(--color-accent-warning), #e06020);
  color: #fff;
}

.calc-field {
  margin-bottom: 18px;
}
.calc-field:last-child {
  margin-bottom: 0;
}
.calc-field label {
  display: block;
  font-size: 12px;
  font-weight: 700;
  color: var(--color-text-label);
  margin-bottom: 8px;
  text-transform: uppercase;
  letter-spacing: 0.06em;
}

.calc-input,
.spec-input {
  width: 100%;
  padding: 12px 16px;
  background: var(--color-bg-input);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  color: var(--color-text-primary);
  font-size: 15px;
  font-family: var(--font-heading);
  transition: all var(--transition-fast);
}
.calc-input:focus,
.spec-input:focus {
  outline: none;
  border-color: var(--color-accent);
  box-shadow: 0 0 0 3px var(--color-accent-glow);
}
.calc-input::placeholder,
.spec-input::placeholder {
  color: var(--color-text-placeholder);
}

.spec-picker {
  display: flex;
  align-items: center;
  gap: 6px;
  flex-wrap: wrap;
  margin-bottom: 10px;
}
.spec-sep {
  color: var(--color-text-muted);
  font-weight: 700;
  font-size: 16px;
}
.spec-select {
  padding: 10px 8px;
  background: var(--color-bg-input);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  color: var(--color-text-primary);
  font-size: 14px;
  font-family: var(--font-heading);
  min-width: 65px;
  cursor: pointer;
  transition: all var(--transition-fast);
}
.spec-select:focus {
  outline: none;
  border-color: var(--color-accent);
  box-shadow: 0 0 0 2px var(--color-accent-glow);
}
.spec-picker .spec-input {
  flex: 1;
  min-width: 110px;
}

/* ========== Results ========== */
.calc-result {
  background: var(--color-bg-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-xl);
  padding: 32px;
  min-height: 120px;
  box-shadow: var(--shadow-card);
}

.calc-empty {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  text-align: center;
  color: var(--color-text-muted);
  padding: 16px;
  gap: 12px;
}
.calc-empty svg {
  opacity: 0.4;
}
.calc-empty p {
  font-size: 15px;
}

.calc-comparison {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 20px;
  margin-bottom: 24px;
  padding-bottom: 24px;
  border-bottom: 1px solid var(--color-border);
}

.calc-col {
  padding: 16px;
  background: var(--color-bg-input);
  border-radius: var(--radius-md);
  border: 1px solid var(--color-border);
}
.calc-label {
  font-size: 12px;
  font-weight: 700;
  color: var(--color-accent);
  margin-bottom: 10px;
  text-transform: uppercase;
  letter-spacing: 1px;
}
.calc-value {
  font-size: 15px;
  color: var(--color-text-body);
  margin-bottom: 6px;
  font-family: var(--font-heading);
  font-weight: 600;
}

.calc-deltas {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
  gap: 12px;
  margin-bottom: 20px;
}
.calc-delta-item {
  padding: 12px 16px;
  background: var(--color-accent-glow);
  border-radius: var(--radius-md);
  font-size: 14px;
  color: var(--color-text-body);
  border: 1px solid var(--color-border-accent);
}
.calc-delta-item strong {
  color: var(--color-accent);
  font-family: var(--font-heading);
  font-weight: 700;
  display: block;
  margin-bottom: 4px;
}

.calc-visuals {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 14px;
  margin: -6px 0 24px;
}
.calc-visuals[hidden] {
  display: none;
}
.calc-visual-card {
  min-width: 0;
  padding: 16px;
  background: var(--color-bg-elevated);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
}
.calc-visual-title {
  margin-bottom: 12px;
  color: var(--color-text-primary);
  font-size: 13px;
  font-weight: 800;
}
.tire-visual {
  min-height: 112px;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 18px;
}
.tire-ring {
  position: relative;
  width: var(--tire-size);
  height: var(--tire-size);
  display: flex;
  align-items: center;
  justify-content: center;
  border: 8px solid #e5e7eb;
  border-radius: 50%;
  background: radial-gradient(circle, #f3f4f6 0 calc(var(--rim-size) / 2), transparent calc(var(--rim-size) / 2 + 1px));
  box-shadow: inset 0 0 0 1px rgba(0, 0, 0, 0.05), 0 4px 12px rgba(0, 0, 0, 0.1);
}
.tire-ring::after {
  content: '';
  position: absolute;
  width: var(--rim-size);
  height: var(--rim-size);
  border: 2px solid #d1d5db;
  border-radius: 50%;
}
.tire-ring span {
  position: relative;
  z-index: 1;
  color: var(--color-text-secondary);
  font-size: 12px;
  font-weight: 900;
}
.tire-ring-new {
  border-color: var(--color-accent);
}
.wheel-offset-visual {
  padding-top: 8px;
}
.wheel-offset-row {
  display: grid;
  grid-template-columns: 28px minmax(0, 1fr) 2px minmax(0, 1fr);
  align-items: center;
  gap: 0;
  min-height: 30px;
  color: var(--color-text-muted);
  font-size: 12px;
  font-weight: 800;
}
.wheel-offset-row i {
  display: block;
  height: 14px;
  justify-self: end;
  background: var(--color-accent-secondary);
  border-radius: 999px 0 0 999px;
}
.wheel-offset-row i:last-child {
  justify-self: start;
  border-radius: 0 999px 999px 0;
}
.wheel-offset-row b {
  width: 2px;
  height: 26px;
  background: var(--color-border);
}
.wheel-offset-row.is-new i {
  background: var(--color-accent);
}
.wheel-offset-axis {
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  gap: 10px;
  margin-left: 28px;
  padding-top: 6px;
  color: var(--color-text-muted);
  font-size: 11px;
}
.wheel-offset-axis span:last-child {
  text-align: right;
}
.calc-visual-note {
  margin-top: 10px;
  color: var(--color-text-muted);
  font-size: 12px;
  line-height: 1.45;
}

.calc-advice {
  grid-column: 1 / -1;
  padding: 18px 20px;
  border-radius: var(--radius-md);
  font-size: 14px;
  line-height: 1.7;
  display: flex;
  align-items: flex-start;
  gap: 12px;
}
.calc-advice::before {
  content: '';
  width: 20px;
  height: 20px;
  border-radius: 50%;
  flex-shrink: 0;
  margin-top: 2px;
}
.calc-advice-ok {
  background: rgba(72, 209, 122, 0.08);
  border: 1px solid rgba(72, 209, 122, 0.25);
  color: var(--color-accent-success);
}
.calc-advice-ok::before {
  background: var(--color-accent-success);
}
.calc-advice-caution {
  background: rgba(255, 122, 47, 0.08);
  border: 1px solid rgba(255, 122, 47, 0.25);
  color: var(--color-accent-warning);
}
.calc-advice-caution::before {
  background: var(--color-accent-warning);
}
.calc-advice-danger {
  background: rgba(255, 95, 86, 0.08);
  border: 1px solid rgba(255, 95, 86, 0.25);
  color: var(--color-accent-danger);
}
.calc-advice-danger::before {
  background: var(--color-accent-danger);
}

/* ========== Reference Section ========== */
.calc-ref-section {
  margin-bottom: 40px;
}

/* ========== Calculator Responsive ========== */
@media (max-width: 900px) {
  .calc-panels {
    grid-template-columns: 1fr;
    gap: 12px;
  }
  .calc-arrow {
    transform: rotate(90deg);
    padding: 8px 0;
  }
}

@media (max-width: 768px) {
  .calc-panels {
    grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
    align-items: stretch;
    gap: 10px;
  }
  .calc-arrow {
    display: none;
  }
  .calc-panel {
    min-width: 0;
    padding: 14px 10px;
    border-radius: var(--radius-lg);
  }
  .calc-panel-header {
    display: block;
    margin-bottom: 14px;
  }
  .calc-panel-header h3 {
    margin-top: 8px;
    font-size: 14px;
    line-height: 1.3;
  }
  .calc-panel-badge {
    padding: 5px 9px;
    font-size: 12px;
  }
  .calc-field {
    margin-bottom: 12px;
  }
  .calc-field label {
    margin-bottom: 6px;
    font-size: 11px;
  }
  .spec-picker {
    display: grid;
    grid-template-columns: minmax(0, 1fr) auto minmax(0, 1fr) auto minmax(0, 1fr);
    gap: 4px;
    margin-bottom: 8px;
  }
  .spec-select {
    width: 100%;
    min-width: 0;
    padding: 10px 4px;
    font-size: 13px;
    text-align: center;
    min-height: 40px;
  }
  .spec-sep {
    font-size: 14px;
    padding: 0 2px;
  }
  .spec-picker .spec-input {
    min-width: 100px;
    min-height: 40px;
    padding: 10px 8px;
    font-size: 14px;
  }
  .calc-input,
  .spec-input {
    padding: 10px 8px;
    font-size: 13px;
  }
  .calc-result {
    padding: 20px;
  }
  .calc-comparison {
    gap: 10px;
    margin-bottom: 16px;
    padding-bottom: 16px;
  }
  .calc-col {
    padding: 12px 10px;
  }
  .calc-label {
    margin-bottom: 6px;
    font-size: 11px;
  }
  .calc-value {
    margin-bottom: 4px;
    font-size: 13px;
  }
  .calc-deltas {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 8px;
    margin-bottom: 14px;
  }
  .calc-delta-item {
    padding: 10px 8px;
    font-size: 12px;
    line-height: 1.35;
  }
  .calc-delta-item strong {
    margin-bottom: 3px;
    font-size: 12px;
  }
  .calc-visuals {
    gap: 8px;
    margin-bottom: 14px;
  }
  .calc-visual-card {
    padding: 10px 8px;
  }
  .calc-visual-title {
    margin-bottom: 8px;
    font-size: 12px;
  }
  .tire-visual {
    min-height: 88px;
    gap: 8px;
  }
  .tire-ring {
    border-width: 6px;
    transform: scale(0.82);
    margin: -8px;
  }
  .wheel-offset-row {
    grid-template-columns: 24px minmax(0, 1fr) 2px minmax(0, 1fr);
    min-height: 26px;
    font-size: 11px;
  }
  .wheel-offset-axis {
    margin-left: 24px;
    gap: 6px;
    font-size: 10px;
  }
  .calc-visual-note {
    margin-top: 8px;
    font-size: 11px;
  }
  .calc-advice {
    padding: 14px 12px;
    font-size: 13px;
    line-height: 1.55;
  }
}

@media (max-width: 420px) {
  .calc-panels {
    gap: 8px;
  }
  .calc-panel {
    padding: 12px 8px;
    min-height: 44px;
  }
  .calc-panel-header h3 {
    font-size: 14px;
    margin-top: 6px;
  }
  .calc-panel-badge {
    padding: 5px 8px;
    font-size: 11px;
  }
  .spec-picker {
    gap: 3px;
    margin-bottom: 6px;
  }
  .spec-select {
    font-size: 12px;
    padding: 10px 3px;
    min-height: 40px;
  }
  .spec-sep {
    font-size: 13px;
    padding: 0 2px;
  }
  .spec-picker .spec-input {
    font-size: 13px;
    min-height: 40px;
    padding: 8px 6px;
  }
  .spec-picker .spec-input:first-of-type {
    min-width: 90px;
  }
  .calc-input,
  .spec-input {
    font-size: 14px;
    padding: 12px 10px;
    min-height: 44px;
  }
  .calc-comparison {
    gap: 8px;
  }
  .calc-col {
    padding: 10px 8px;
  }
  .calc-deltas {
    gap: 6px;
  }
  .calc-delta-item {
    padding: 8px 6px;
    font-size: 11px;
  }
  .calc-delta-item strong {
    font-size: 11px;
  }
  .calc-visuals {
    gap: 6px;
  }
  .calc-visual-card {
    padding: 8px 6px;
  }
  .tire-ring {
    transform: scale(0.72);
    margin: -12px;
  }
  .wheel-offset-axis {
    display: none;
  }
}

/* 小程序引导横幅 */
.calc-qr-banner {
  margin-top: 20px;
}
.calc-qr-card {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 16px;
  background: var(--color-bg-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: 16px 20px;
}
.calc-qr-card img {
  border-radius: var(--radius-md);
  flex-shrink: 0;
}
.calc-qr-title {
  font-size: 15px;
  font-weight: 600;
  color: var(--color-text-primary);
  margin-bottom: 4px;
}
.calc-qr-text p {
  font-size: 13px;
  color: var(--color-text-secondary);
  margin: 0;
  line-height: 1.5;
}