/* === CSS Custom Properties === */
:root {
  --color-primary: #2563eb;
  --color-primary-dark: #1d4ed8;
  --color-primary-light: #dbeafe;
  --color-success: #16a34a;
  --color-warning: #d97706;
  --color-error: #dc2626;
  --color-bg: #f8fafc;
  --color-surface: #ffffff;
  --color-text: #1e293b;
  --color-text-secondary: #64748b;
  --color-border: #e2e8f0;
  --font-sans: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --radius: 8px;
  --shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
  --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.1);
}

/* === Reset and Base === */
*,
*::before,
*::after {
  box-sizing: border-box;
}

* {
  margin: 0;
  padding: 0;
}

body {
  font-family: var(--font-sans);
  color: var(--color-text);
  background-color: var(--color-bg);
  line-height: 1.6;
  min-height: 100vh;
}

img {
  max-width: 100%;
  display: block;
}

/* === Layout === */
.container {
  max-width: 800px;
  margin: 0 auto;
  padding: 0 1rem;
}

.section {
  margin-bottom: 2rem;
}

/* === Typography === */
h1 {
  font-size: 1.75rem;
  font-weight: 700;
  margin-bottom: 0.5rem;
  line-height: 1.2;
}

h2 {
  font-size: 1.375rem;
  font-weight: 700;
  margin-bottom: 0.75rem;
  line-height: 1.3;
}

h3 {
  font-size: 1.125rem;
  font-weight: 600;
  margin-bottom: 0.5rem;
  line-height: 1.4;
}

p {
  margin-bottom: 1rem;
}

a {
  color: var(--color-primary);
  text-decoration: underline;
}

a:hover {
  color: var(--color-primary-dark);
}

/* === Navigation === */
.nav {
  background-color: var(--color-surface);
  border-bottom: 1px solid var(--color-border);
  padding: 0.75rem 0;
  position: sticky;
  top: 0;
  z-index: 100;
}

.nav-container {
  max-width: 800px;
  margin: 0 auto;
  padding: 0 1rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.nav-brand {
  font-weight: 700;
  font-size: 1.125rem;
  color: var(--color-primary);
  text-decoration: none;
}

.nav-brand:hover {
  color: var(--color-primary-dark);
}

.nav-links {
  display: flex;
  gap: 1rem;
  list-style: none;
}

.nav-links a {
  color: var(--color-text-secondary);
  text-decoration: none;
  font-size: 0.875rem;
  font-weight: 500;
}

.nav-links a:hover {
  color: var(--color-primary);
}

/* === Cards === */
.card {
  background-color: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 1.5rem;
  box-shadow: var(--shadow);
}

.card-header {
  border-bottom: 1px solid var(--color-border);
  padding-bottom: 1rem;
  margin-bottom: 1.25rem;
}

.card-header h2 {
  margin-bottom: 0;
}

/* === Hero === */
.hero {
  padding: 2rem 0 1.5rem;
  text-align: center;
}

.hero-subtitle {
  color: var(--color-text-secondary);
  font-size: 1.05rem;
  max-width: 600px;
  margin: 0.5rem auto 0;
}

/* === Calculator Form === */
.calculator-form {
  display: grid;
  gap: 1.25rem;
}

.form-group {
  display: flex;
  flex-direction: column;
  gap: 0.25rem;
}

.form-group label {
  font-weight: 600;
  font-size: 0.875rem;
  color: var(--color-text);
}

.form-group input {
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 0.625rem 0.75rem;
  font-size: 1rem;
  width: 100%;
  font-family: var(--font-sans);
  transition: border-color 0.15s ease, box-shadow 0.15s ease;
}

.form-group input:focus {
  outline: none;
  border-color: var(--color-primary);
  box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.15);
}

.input-hint {
  font-size: 0.75rem;
  color: var(--color-text-secondary);
}

/* === Error States === */
.error-message {
  color: var(--color-error);
  background-color: #fef2f2;
  border: 1px solid #fecaca;
  border-radius: var(--radius);
  padding: 0.75rem 1rem;
  font-size: 0.875rem;
  font-weight: 500;
  margin: 0 1rem 1rem;
}

.input-error {
  border-color: var(--color-error) !important;
  box-shadow: 0 0 0 3px rgba(220, 38, 38, 0.15) !important;
}

/* === Buttons === */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.625rem 1.25rem;
  border-radius: var(--radius);
  font-weight: 600;
  font-size: 0.875rem;
  font-family: var(--font-sans);
  cursor: pointer;
  border: 1px solid transparent;
  transition: background-color 0.15s ease, border-color 0.15s ease, box-shadow 0.15s ease;
}

.btn:focus {
  outline: none;
  box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.2);
}

.btn-primary {
  background-color: var(--color-primary);
  color: #ffffff;
  border-color: var(--color-primary);
}

.btn-primary:hover {
  background-color: var(--color-primary-dark);
  border-color: var(--color-primary-dark);
}

.btn-secondary {
  background-color: var(--color-surface);
  color: var(--color-text-secondary);
  border-color: var(--color-border);
}

.btn-secondary:hover {
  background-color: var(--color-bg);
  border-color: var(--color-text-secondary);
}

.btn-example {
  background-color: var(--color-primary-light);
  color: var(--color-primary-dark);
  border-color: var(--color-primary-light);
}

.btn-example:hover {
  background-color: #bfdbfe;
  border-color: #bfdbfe;
}

.btn-group {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  margin-top: 0.5rem;
}

/* === Result Panel === */
.result-card {
  text-align: center;
}

.result-score {
  font-size: 4rem;
  font-weight: 800;
  margin: 1rem 0 0.5rem;
  line-height: 1;
}

.result-score.score-5 {
  color: var(--color-success);
}

.result-score.score-4 {
  color: #22c55e;
}

.result-score.score-3 {
  color: var(--color-warning);
}

.result-score.score-2 {
  color: #f97316;
}

.result-score.score-1 {
  color: var(--color-error);
}

.result-interpretation {
  color: var(--color-text-secondary);
  font-size: 1rem;
  margin-bottom: 1.5rem;
}

.result-composite {
  margin-bottom: 1.5rem;
  text-align: left;
}

.result-composite h3 {
  margin-bottom: 0.5rem;
}

.composite-display {
  font-size: 1.25rem;
  font-weight: 700;
  margin-bottom: 0.5rem;
  text-align: center;
}

.progress-bar {
  height: 12px;
  background-color: var(--color-border);
  border-radius: 6px;
  overflow: hidden;
}

.progress-fill {
  height: 100%;
  background-color: var(--color-primary);
  border-radius: 6px;
  transition: width 0.4s ease;
}

/* === Section Breakdown === */
.result-breakdown {
  text-align: left;
  margin-bottom: 1.5rem;
}

.result-breakdown h3 {
  margin-bottom: 0.75rem;
}

.contribution-item {
  display: grid;
  grid-template-columns: 100px 1fr 50px;
  align-items: center;
  gap: 0.75rem;
  margin-bottom: 0.5rem;
}

.contribution-label {
  font-size: 0.8rem;
  font-weight: 600;
  color: var(--color-text-secondary);
}

.contribution-bar-container {
  height: 10px;
  background-color: var(--color-border);
  border-radius: 5px;
  overflow: hidden;
}

.contribution-bar {
  height: 100%;
  border-radius: 5px;
  transition: width 0.4s ease;
}

.mcq-bar {
  background-color: #3b82f6;
}

.saq-bar {
  background-color: #8b5cf6;
}

.dbq-bar {
  background-color: #06b6d4;
}

.leq-bar {
  background-color: #f59e0b;
}

.contribution-value {
  font-size: 0.8rem;
  font-weight: 600;
  text-align: right;
}

.next-score-message {
  background-color: var(--color-primary-light);
  color: var(--color-primary-dark);
  padding: 0.75rem 1rem;
  border-radius: var(--radius);
  font-size: 0.9rem;
  font-weight: 500;
}

/* === Content Sections === */
.content-section {
  margin-bottom: 2.5rem;
}

.content-section h2 {
  margin-bottom: 1rem;
  padding-bottom: 0.5rem;
  border-bottom: 2px solid var(--color-primary-light);
}

.content-section p {
  margin-bottom: 0.75rem;
}

.content-section ul,
.content-section ol {
  margin-bottom: 1rem;
  padding-left: 1.5rem;
}

.content-section li {
  margin-bottom: 0.4rem;
}

/* === Tables === */
table {
  width: 100%;
  border-collapse: collapse;
  margin-bottom: 1rem;
  font-size: 0.875rem;
}

thead th {
  background-color: var(--color-bg);
  font-weight: 700;
  text-align: left;
  padding: 0.75rem;
  border-bottom: 2px solid var(--color-border);
}

tbody td {
  padding: 0.625rem 0.75rem;
  border-bottom: 1px solid var(--color-border);
}

tbody tr:nth-child(even) {
  background-color: var(--color-bg);
}

/* === FAQ === */
.faq-item {
  margin-bottom: 1.25rem;
  padding-bottom: 1.25rem;
  border-bottom: 1px solid var(--color-border);
}

.faq-item:last-child {
  border-bottom: none;
  padding-bottom: 0;
  margin-bottom: 0;
}

.faq-item h3 {
  color: var(--color-text);
  margin-bottom: 0.4rem;
}

.faq-item p {
  color: var(--color-text-secondary);
  margin-bottom: 0;
}

/* === Disclaimer === */
.disclaimer-card {
  background-color: #fffbeb;
  border: 1px solid #fde68a;
  border-left: 4px solid var(--color-warning);
  border-radius: var(--radius);
  padding: 1rem 1.25rem;
  font-size: 0.875rem;
  color: #92400e;
}

/* === Calculator Cards Grid (Homepage) === */
.calculator-grid {
  display: grid;
  gap: 1rem;
}

.calculator-link-card {
  display: block;
  text-decoration: none;
  color: inherit;
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  background-color: var(--color-surface);
  padding: 1.25rem;
  box-shadow: var(--shadow);
  transition: box-shadow 0.15s ease, border-color 0.15s ease;
}

.calculator-link-card:hover {
  box-shadow: var(--shadow-md);
  border-color: var(--color-primary);
}

.calculator-link-card h3 {
  color: var(--color-primary);
  margin-bottom: 0.4rem;
}

.calculator-link-card p {
  color: var(--color-text-secondary);
  font-size: 0.875rem;
  margin-bottom: 0;
}

.badge {
  display: inline-block;
  font-size: 0.7rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  padding: 0.2rem 0.5rem;
  border-radius: 4px;
  background-color: var(--color-primary-light);
  color: var(--color-primary-dark);
  margin-left: 0.5rem;
  vertical-align: middle;
}

.badge-coming-soon {
  background-color: #fef3c7;
  color: #92400e;
}

/* === Footer === */
.footer {
  border-top: 1px solid var(--color-border);
  padding: 1.5rem 0;
  text-align: center;
  color: var(--color-text-secondary);
  font-size: 0.8rem;
  margin-top: 2rem;
}

.footer p {
  margin-bottom: 0.25rem;
}

/* === About Section === */
.about-section {
  padding: 1.5rem 0;
}

/* === Coming Soon Page === */
.coming-soon {
  text-align: center;
  padding: 3rem 0;
}

.coming-soon p {
  color: var(--color-text-secondary);
  max-width: 500px;
  margin: 1rem auto;
}

/* === Responsive (Tablet+) === */
@media (min-width: 768px) {
  h1 {
    font-size: 2.25rem;
  }

  h2 {
    font-size: 1.5rem;
  }

  .hero {
    padding: 3rem 0 2rem;
  }

  .calculator-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .calculator-form {
    grid-template-columns: 1fr 1fr;
  }

  .btn-group {
    grid-column: 1 / -1;
  }

  .form-group input {
    padding: 0.75rem 1rem;
  }

  .contribution-item {
    grid-template-columns: 120px 1fr 60px;
  }

  .container {
    padding: 0 1.5rem;
  }
}


.keyword-chip-list {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  margin-top: 1.25rem;
}

.keyword-chip-list a {
  display: inline-flex;
  align-items: center;
  border: 1px solid rgba(37, 99, 235, 0.22);
  background: rgba(37, 99, 235, 0.08);
  color: #1d4ed8;
  padding: 0.55rem 0.8rem;
  border-radius: 999px;
  text-decoration: none;
  font-weight: 600;
}

.keyword-chip-list a:hover,
.keyword-chip-list a:focus {
  background: rgba(37, 99, 235, 0.14);
  text-decoration: underline;
}

.center-actions {
  justify-content: center;
  margin-top: 2rem;
}

.not-found {
  min-height: 48vh;
}