/* ==========================================================================
   CalculatorHub - Percentage Calculator Stylesheet
   Theme: CalculatorHub Light Master Design System
   Compatible with: styles.css tokens & components
   ========================================================================== */

/* --- Breadcrumbs --- */
.breadcrumb-nav {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 0.5rem;
  font-size: 0.8125rem;
  color: var(--text-muted);
  margin-bottom: 1.25rem;
}

.breadcrumb-link {
  color: var(--text-muted);
  transition: color var(--transition-fast);
}

.breadcrumb-link:hover {
  color: var(--primary);
}

.breadcrumb-separator {
  color: var(--text-subtle);
  font-size: 0.75rem;
}

.breadcrumb-current {
  color: var(--text-main);
  font-weight: 600;
}

/* --- Hero Intro --- */
.pct-hero {
  padding-top: 2.5rem;
  padding-bottom: 2rem;
  background: radial-gradient(circle at 50% -20%, rgba(37, 99, 235, 0.07) 0%, transparent 70%);
}

@media (max-width: 640px) {
  .pct-hero {
    padding-top: 1.75rem;
    padding-bottom: 1.5rem;
  }
}

.pct-badge {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  padding: 0.35rem 0.85rem;
  background-color: var(--primary-light);
  color: var(--primary);
  font-size: 0.8125rem;
  font-weight: 700;
  border-radius: var(--radius-full);
  margin-bottom: 0.75rem;
  letter-spacing: 0.04em;
  text-transform: uppercase;
}

.pct-page-title {
  font-size: 2.25rem;
  font-weight: 800;
  color: var(--text-main);
  letter-spacing: -0.03em;
  line-height: 1.2;
  margin-bottom: 0.65rem;
}

@media (max-width: 640px) {
  .pct-page-title {
    font-size: 1.875rem;
  }
}

.pct-page-subtitle {
  font-size: 1.0625rem;
  color: var(--text-muted);
  max-width: 720px;
  line-height: 1.6;
}

/* --- Mode Tabs Bar --- */
.pct-mode-tabs-wrapper {
  width: 100%;
  max-width: 100%;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
  margin-bottom: 1.5rem;
  scrollbar-width: none;
}

.pct-mode-tabs-wrapper::-webkit-scrollbar {
  display: none;
}

.pct-mode-tabs {
  display: inline-flex;
  background-color: var(--bg-subtle);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 4px;
  gap: 4px;
  min-width: 100%;
}

@media (min-width: 768px) {
  .pct-mode-tabs {
    display: flex;
    width: 100%;
  }
}

.pct-mode-tab {
  flex: 1;
  padding: 0.65rem 0.85rem;
  font-size: 0.875rem;
  font-weight: 600;
  color: var(--text-muted);
  border-radius: var(--radius-md);
  transition: all var(--transition-fast);
  text-align: center;
  white-space: nowrap;
  min-height: 44px;
  display: flex;
  align-items: center;
  justify-content: center;
}

.pct-mode-tab.is-active {
  background-color: #ffffff;
  color: var(--primary);
  box-shadow: var(--shadow-sm);
  font-weight: 700;
}

.pct-mode-tab:hover:not(.is-active) {
  color: var(--text-main);
}

/* --- Main Calculator Layout --- */
.pct-calc-section {
  padding-bottom: 3.5rem;
}

.pct-calc-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 2rem;
  align-items: start;
}

@media (min-width: 1024px) {
  .pct-calc-grid {
    grid-template-columns: 1.15fr 0.85fr;
    gap: 2.5rem;
  }
}

/* Card Shell */
.pct-card {
  background-color: var(--bg-surface);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-xl);
  padding: 1.875rem;
  box-shadow: var(--shadow-md);
  position: relative;
}

@media (max-width: 640px) {
  .pct-card {
    padding: 1.25rem;
  }
}

.pct-card-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-bottom: 1.25rem;
  margin-bottom: 1.5rem;
  border-bottom: 1px solid var(--border-color);
}

.pct-card-title {
  font-size: 1.125rem;
  font-weight: 700;
  color: var(--text-main);
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.pct-tag-badge {
  font-size: 0.6875rem;
  font-weight: 700;
  background-color: var(--bg-subtle);
  color: var(--text-muted);
  padding: 0.2rem 0.55rem;
  border-radius: var(--radius-full);
  letter-spacing: 0.04em;
}

/* Form Groups & Controls */
.pct-form {
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
}

.pct-input-group {
  display: flex;
  flex-direction: column;
  gap: 0.55rem;
}

.pct-label-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.pct-label {
  font-size: 0.9375rem;
  font-weight: 600;
  color: var(--text-main);
}

.pct-input-wrapper {
  position: relative;
  display: flex;
  align-items: center;
}

.pct-affix {
  position: absolute;
  font-size: 1rem;
  font-weight: 600;
  color: var(--text-muted);
  pointer-events: none;
  user-select: none;
}

.pct-prefix {
  left: 1rem;
}

.pct-suffix {
  right: 1rem;
}

.pct-input-text {
  width: 100%;
  min-width: 0;
  max-width: 100%;
  padding: 0.75rem 1rem;
  background-color: #ffffff;
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  font-size: 1.0625rem;
  font-weight: 600;
  color: var(--text-main);
  transition: all var(--transition-fast);
  min-height: 48px;
}

.pct-input-text:focus {
  outline: none;
  border-color: var(--primary);
  box-shadow: 0 0 0 3px var(--primary-ring);
}

.has-prefix {
  padding-left: 2.25rem;
}

.has-suffix {
  padding-right: 2.5rem;
}

/* Quick Examples Box */
.quick-examples-box {
  background-color: var(--bg-page);
  border: 1px dashed var(--border-color);
  border-radius: var(--radius-md);
  padding: 1rem 1.15rem;
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.quick-examples-title {
  font-size: 0.8125rem;
  font-weight: 700;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.04em;
}

.example-chips-row {
  display: flex;
  flex-wrap: wrap;
  gap: 0.45rem;
}

.example-chip {
  background-color: #ffffff;
  border: 1px solid var(--border-color);
  color: var(--text-body);
  font-size: 0.8125rem;
  font-weight: 600;
  padding: 0.35rem 0.75rem;
  border-radius: var(--radius-full);
  transition: all var(--transition-fast);
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  min-height: 38px;
}

.example-chip:hover {
  background-color: var(--primary-light);
  color: var(--primary);
  border-color: #bfdbfe;
  transform: translateY(-1px);
}

/* Actions Row */
.pct-actions-row {
  display: flex;
  gap: 0.75rem;
  margin-top: 0.5rem;
}

.btn-calc-submit {
  flex: 2;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 0.95rem 1.5rem;
  background-color: var(--primary);
  color: #ffffff;
  font-size: 1.0625rem;
  font-weight: 700;
  border-radius: var(--radius-lg);
  box-shadow: 0 4px 12px rgba(37, 99, 235, 0.25);
  transition: all var(--transition-fast);
  min-height: 48px;
}

.btn-calc-submit:hover,
.btn-calc-submit:focus-visible {
  background-color: var(--primary-hover);
  transform: translateY(-2px);
  box-shadow: 0 6px 16px rgba(37, 99, 235, 0.35);
}

.btn-calc-submit:active {
  transform: translateY(0);
}

.btn-calc-reset {
  flex: 1;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.4rem;
  padding: 0.95rem 1rem;
  background-color: var(--bg-subtle);
  color: var(--text-body);
  font-size: 0.9375rem;
  font-weight: 600;
  border-radius: var(--radius-lg);
  border: 1px solid var(--border-color);
  transition: all var(--transition-fast);
  min-height: 48px;
}

.btn-calc-reset:hover {
  background-color: #e2e8f0;
  color: var(--text-main);
}

/* --- Results Card --- */
.pct-results-card {
  display: flex;
  flex-direction: column;
}

.pct-main-result-box {
  background-color: var(--primary-light);
  border: 1px solid rgba(37, 99, 235, 0.15);
  border-radius: var(--radius-lg);
  padding: 1.65rem 1.5rem;
  text-align: center;
  margin-bottom: 1.5rem;
}

.pct-result-label {
  font-size: 0.875rem;
  font-weight: 600;
  color: var(--text-muted);
  margin-bottom: 0.35rem;
}

.pct-result-val {
  font-size: 2.625rem;
  font-weight: 800;
  color: var(--primary);
  line-height: 1.1;
  letter-spacing: -0.025em;
  font-family: var(--font-sans);
}

@media (max-width: 480px) {
  .pct-result-val {
    font-size: 2.125rem;
  }
}

.pct-result-summary {
  font-size: 0.875rem;
  color: var(--text-body);
  margin-top: 0.65rem;
  font-weight: 600;
}

/* Step-by-Step Explanation Block */
.pct-explanation-box {
  background-color: var(--bg-page);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 1.15rem;
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
  margin-bottom: 1.5rem;
}

.pct-expl-row {
  display: flex;
  flex-direction: column;
  gap: 0.25rem;
}

.pct-expl-label {
  font-size: 0.75rem;
  font-weight: 700;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.04em;
}

.pct-expl-code {
  font-family: var(--font-mono, monospace);
  font-size: 0.875rem;
  font-weight: 600;
  color: var(--text-main);
  background-color: #ffffff;
  border: 1px solid var(--border-color);
  border-radius: var(--radius-sm);
  padding: 0.4rem 0.65rem;
  word-break: break-all;
}

/* Copy Button */
.btn-calc-copy {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.4rem;
  width: 100%;
  padding: 0.75rem 1rem;
  background-color: var(--bg-subtle);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  font-size: 0.875rem;
  font-weight: 600;
  color: var(--text-body);
  transition: all var(--transition-fast);
  min-height: 44px;
}

.btn-calc-copy:hover {
  background-color: #e2e8f0;
  color: var(--text-main);
}

/* --- Specialized Business & Shopping Tools Section --- */
.specialized-section {
  padding-bottom: 3.5rem;
}

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

@media (min-width: 900px) {
  .specialized-grid {
    grid-template-columns: repeat(3, 1fr);
  }
}

.shop-presets-row {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
  margin-top: 0.25rem;
}

.shop-preset-chip {
  flex: 1;
  background-color: var(--bg-page);
  border: 1px solid var(--border-color);
  color: var(--text-body);
  font-size: 0.8125rem;
  font-weight: 600;
  padding: 0.35rem 0.5rem;
  border-radius: var(--radius-sm);
  text-align: center;
  transition: all var(--transition-fast);
  min-height: 38px;
}

.shop-preset-chip:hover {
  background-color: var(--primary-light);
  color: var(--primary);
}

.shop-preset-chip.is-active {
  background-color: var(--primary);
  color: #ffffff;
  border-color: var(--primary);
}

.shop-stats-list {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
  background-color: var(--bg-page);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 1rem;
  margin-top: 1rem;
}

.shop-stat-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 0.875rem;
}

.shop-stat-label {
  color: var(--text-muted);
}

.shop-stat-val {
  font-weight: 700;
  color: var(--text-main);
}

.shop-stat-val.highlight {
  color: var(--primary);
}

.shop-stat-val.savings {
  color: #10b981;
}

.revdisc-error-box {
  background-color: #fee2e2;
  border: 1px solid #fca5a5;
  color: #b91c1c;
  padding: 0.65rem 0.85rem;
  border-radius: var(--radius-sm);
  font-size: 0.8125rem;
  font-weight: 600;
  margin-top: 0.75rem;
  display: none;
}

/* --- Educational & Content Cards --- */
.content-section {
  padding-bottom: 3.5rem;
}

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

@media (min-width: 1024px) {
  .content-grid {
    grid-template-columns: 1.2fr 0.8fr;
  }
}

.article-card {
  background-color: var(--bg-surface);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-xl);
  padding: 2.25rem;
  box-shadow: var(--shadow-sm);
  display: flex;
  flex-direction: column;
  gap: 1.75rem;
}

@media (max-width: 640px) {
  .article-card {
    padding: 1.35rem;
  }
}

.article-heading {
  font-size: 1.35rem;
  font-weight: 700;
  color: var(--text-main);
  margin-bottom: 0.5rem;
}

.article-subheading {
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--text-main);
  margin-top: 0.5rem;
  margin-bottom: 0.35rem;
}

.article-p {
  font-size: 0.95rem;
  line-height: 1.65;
  color: var(--text-body);
}

/* Formula Box */
.formula-box {
  background-color: var(--bg-page);
  border: 1px solid var(--border-color);
  border-left: 4px solid var(--primary);
  border-radius: var(--radius-md);
  padding: 1.25rem 1.5rem;
  overflow-x: auto;
  max-width: 100%;
}

.formula-display {
  font-family: var(--font-mono, monospace);
  font-size: 1rem;
  font-weight: 700;
  color: var(--primary);
  margin-bottom: 0.75rem;
  letter-spacing: 0.02em;
  word-break: break-word;
  overflow-wrap: break-word;
}

.formula-vars-list {
  display: flex;
  flex-direction: column;
  gap: 0.35rem;
  font-size: 0.875rem;
  color: var(--text-body);
}

/* Steps List */
.steps-list {
  display: flex;
  flex-direction: column;
  gap: 1rem;
  counter-reset: pct-steps;
}

.step-item {
  display: flex;
  gap: 1rem;
  align-items: flex-start;
}

.step-number {
  counter-increment: pct-steps;
  width: 1.875rem;
  height: 1.875rem;
  border-radius: 50%;
  background-color: var(--primary-light);
  color: var(--primary);
  font-weight: 700;
  font-size: 0.875rem;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  margin-top: 0.1rem;
}

.step-text {
  font-size: 0.9375rem;
  color: var(--text-body);
  line-height: 1.55;
}

/* Related Calculators Grid */
.related-section {
  padding-bottom: 4rem;
}

.related-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1.25rem;
}

@media (min-width: 640px) {
  .related-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (min-width: 1024px) {
  .related-grid {
    grid-template-columns: repeat(4, 1fr);
  }
}

.related-card {
  background-color: var(--bg-surface);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 1.5rem;
  display: flex;
  flex-direction: column;
  transition: all var(--transition-normal);
  box-shadow: var(--shadow-sm);
  text-decoration: none;
  color: inherit;
}

.related-card:hover {
  transform: translateY(-3px);
  border-color: rgba(37, 99, 235, 0.4);
  box-shadow: var(--shadow-card-hover);
}

.related-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 0.85rem;
}

.related-title {
  font-size: 1.0625rem;
  font-weight: 700;
  color: var(--text-main);
  margin-bottom: 0.4rem;
}

.related-desc {
  font-size: 0.875rem;
  color: var(--text-muted);
  line-height: 1.5;
  margin-bottom: 1rem;
  flex-grow: 1;
}

.related-action {
  font-size: 0.8125rem;
  font-weight: 600;
  color: var(--primary);
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
}

/* Disclaimer Box */
.disclaimer-card {
  background-color: var(--bg-page);
  border: 1px dashed var(--border-color);
  border-radius: var(--radius-md);
  padding: 1.15rem 1.35rem;
  font-size: 0.8125rem;
  color: var(--text-muted);
  line-height: 1.55;
  display: flex;
  align-items: flex-start;
  gap: 0.75rem;
  margin-top: 1.5rem;
}

.disclaimer-card svg {
  width: 1.15rem;
  height: 1.15rem;
  flex-shrink: 0;
  margin-top: 0.1rem;
  color: var(--accent-amber);
}

/* Responsive adjustments for compact screens (320px - 480px) */
@media (max-width: 480px) {
  .formula-display {
    font-size: 0.9375rem;
  }
}

@media (max-width: 440px) {
  .pct-actions-row {
    flex-direction: column;
  }
  .btn-calc-submit,
  .btn-calc-reset {
    width: 100%;
  }
}

@media (max-width: 360px) {
  .pct-card {
    padding: 1rem 0.875rem;
  }
  .pct-result-val {
    font-size: 1.875rem;
  }
  .formula-box {
    padding: 0.875rem;
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
  }
  .formula-display {
    font-size: 0.8125rem;
  }
}