/* ============================================================
   iDeCo 節税シミュレーター — style.css
   ジャンル: 計算・金融
   カラー: #1d4ed8 (プライマリ) / #198754 (グリーン)
   ============================================================ */

:root {
  --primary:        #1d4ed8;
  --primary-hover:  #1e40af;
  --primary-rgb:    29, 78, 216;
  --green:          #198754;
  --green-hover:    #157347;
  --green-rgb:      25, 135, 84;
  --indigo:         #4f46e5;
  --indigo-rgb:     79, 70, 229;
  --bg:             #f9f7f4;
  --surface:        #ffffff;
  --text:           #1a1a2e;
  --text-muted:     #6b7280;
  --text-weak:      #9ca3af;
  --border:         #e2e8f0;
  --radius:         12px;
  --radius-sm:      8px;
  --shadow:         0 1px 3px rgba(0,0,0,0.06), 0 4px 12px rgba(0,0,0,0.08);
  --shadow-hover:   0 4px 16px rgba(0,0,0,0.10), 0 1px 4px rgba(0,0,0,0.06);
  --transition:     0.15s ease;
}

/* ---- Reset ---- */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html { scroll-behavior: smooth; }

body {
  font-family: 'BIZ UDPGothic', -apple-system, BlinkMacSystemFont, "Hiragino Sans", "Noto Sans JP", "Yu Gothic Medium", sans-serif;
  font-size: 0.9375rem;
  line-height: 1.75;
  color: var(--text);
  background: var(--bg);
  overflow-x: hidden;
  word-break: break-word;
}

/* ---- Header ---- */
header {
  background: linear-gradient(135deg, var(--primary) 0%, #2563eb 60%, #1e40af 100%);
  color: #fff;
  padding: 2rem 1.25rem 1.75rem;
  text-align: center;
}

.header-inner {
  max-width: 720px;
  margin: 0 auto;
}

.header-badge {
  display: inline-flex;
  align-items: center;
  gap: 0.375rem;
  background: rgba(255,255,255,0.18);
  border: 1px solid rgba(255,255,255,0.3);
  border-radius: 100px;
  padding: 0.25rem 0.875rem;
  font-size: 0.8125rem;
  font-weight: 600;
  margin-bottom: 0.75rem;
  letter-spacing: 0.02em;
}

header h1 {
  font-family: 'Outfit', sans-serif;
  font-size: clamp(1.4rem, 4vw, 2rem);
  font-weight: 800;
  letter-spacing: -0.01em;
  line-height: 1.3;
}

.subtitle {
  font-size: 0.9rem;
  opacity: 0.88;
  margin-top: 0.5rem;
}

/* ---- Main Layout ---- */
main {
  max-width: 800px;
  margin: 0 auto;
  padding: 1.25rem 1rem 2rem;
}

/* ---- Ad Units ---- */
.ad-unit {
  min-height: 0;
  margin: 1.5rem 0;
}

/* ---- Privacy Notice ---- */
.privacy-notice {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  background: #eff6ff;
  border: 1px solid #bfdbfe;
  border-radius: var(--radius-sm);
  padding: 0.625rem 1rem;
  font-size: 0.8125rem;
  color: #1e40af;
  margin-bottom: 1.25rem;
}

.privacy-notice i {
  font-size: 1rem;
  flex-shrink: 0;
}

/* ---- Section Title ---- */
.section-title {
  font-family: 'Outfit', sans-serif;
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--text);
  margin-bottom: 1.25rem;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.section-title i {
  color: var(--primary);
}

/* ---- Tool Section ---- */
.tool-section {
  background: var(--surface);
  border-radius: var(--radius);
  padding: 1.5rem;
  box-shadow: var(--shadow);
  border: 1px solid rgba(0,0,0,0.05);
  margin-bottom: 1.25rem;
}

/* ---- Form Grid ---- */
.form-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1.25rem;
}

.field-full {
  grid-column: 1 / -1;
}

/* ---- Field ---- */
.field {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.field-label {
  font-size: 0.875rem;
  font-weight: 700;
  color: #374151;
  display: flex;
  align-items: center;
  gap: 0.375rem;
}

.field-label i {
  color: var(--primary);
  font-size: 0.9375rem;
}

.field-hint {
  font-size: 0.8125rem;
  color: var(--text-muted);
}

/* ---- Badge ---- */
.badge {
  display: inline-block;
  background: #dbeafe;
  color: var(--primary);
  border-radius: 100px;
  padding: 0.125rem 0.625rem;
  font-size: 0.75rem;
  font-weight: 600;
  margin-left: auto;
}

/* ---- Select & Input ---- */
select,
input[type="number"] {
  border: 1.5px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 0.5rem 0.75rem;
  font-size: 1rem;
  font-family: inherit;
  background: #fff;
  color: var(--text);
  transition: border-color var(--transition), box-shadow var(--transition);
  min-height: 44px;
  width: 100%;
  appearance: none;
  -webkit-appearance: none;
}

select {
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' viewBox='0 0 16 16'%3E%3Cpath fill='%236b7280' d='M7.247 11.14 2.451 5.658C1.885 5.013 2.345 4 3.204 4h9.592a1 1 0 0 1 .753 1.659l-4.796 5.48a1 1 0 0 1-1.506 0z'/%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right 0.75rem center;
  padding-right: 2.25rem;
  cursor: pointer;
}

select:focus,
input[type="number"]:focus {
  outline: none;
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(var(--primary-rgb), 0.15);
}

/* ---- Input with Unit ---- */
.input-with-unit {
  display: flex;
  align-items: stretch;
  border: 1.5px solid var(--border);
  border-radius: var(--radius-sm);
  overflow: hidden;
  transition: border-color var(--transition), box-shadow var(--transition);
  min-height: 44px;
}

.input-with-unit:focus-within {
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(var(--primary-rgb), 0.15);
}

.input-with-unit input[type="number"] {
  border: none;
  border-radius: 0;
  flex: 1;
  min-width: 0;
}

.input-with-unit input[type="number"]:focus {
  box-shadow: none;
}

.unit {
  display: flex;
  align-items: center;
  padding: 0 0.75rem;
  background: #f8fafc;
  border-left: 1.5px solid var(--border);
  font-size: 0.875rem;
  color: var(--text-muted);
  white-space: nowrap;
  flex-shrink: 0;
}

/* ---- Slider ---- */
.slider-row {
  display: flex;
  align-items: center;
  gap: 0.875rem;
}

input[type="range"] {
  flex: 1;
  height: 6px;
  border-radius: 100px;
  background: linear-gradient(to right, var(--primary) 0%, var(--primary) 43%, #e2e8f0 43%, #e2e8f0 100%);
  border: none;
  outline: none;
  cursor: pointer;
  appearance: none;
  -webkit-appearance: none;
  min-height: 0;
}

input[type="range"]::-webkit-slider-thumb {
  appearance: none;
  -webkit-appearance: none;
  width: 22px;
  height: 22px;
  border-radius: 50%;
  background: var(--primary);
  border: 2px solid #fff;
  box-shadow: 0 1px 4px rgba(29,78,216,0.4);
  cursor: pointer;
  transition: transform var(--transition), box-shadow var(--transition);
}

input[type="range"]::-webkit-slider-thumb:hover {
  transform: scale(1.15);
  box-shadow: 0 2px 8px rgba(29,78,216,0.5);
}

input[type="range"]::-moz-range-thumb {
  width: 22px;
  height: 22px;
  border-radius: 50%;
  background: var(--primary);
  border: 2px solid #fff;
  box-shadow: 0 1px 4px rgba(29,78,216,0.4);
  cursor: pointer;
}

.slider-input {
  flex-shrink: 0;
  width: 140px;
}

.slider-labels {
  display: flex;
  justify-content: space-between;
  font-size: 0.75rem;
  color: var(--text-weak);
  margin-top: 4px;
}

/* ---- Button ---- */
.btn-primary {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  width: 100%;
  margin-top: 1.5rem;
  padding: 0.75rem 1.5rem;
  font-size: 1rem;
  font-weight: 700;
  font-family: inherit;
  background: var(--primary);
  color: #fff;
  border: none;
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: background var(--transition), transform 0.12s ease, box-shadow var(--transition);
  min-height: 52px;
  box-shadow: 0 2px 8px rgba(var(--primary-rgb), 0.35);
  letter-spacing: 0.01em;
}

.btn-primary:hover {
  background: var(--primary-hover);
  transform: translateY(-1px);
  box-shadow: 0 4px 12px rgba(var(--primary-rgb), 0.4);
}

.btn-primary:active {
  transform: translateY(0);
  box-shadow: none;
}

/* ---- Result Section ---- */
.result-section {
  margin-top: 1.25rem;
}

.result-section .section-title {
  margin-bottom: 1rem;
}

/* ---- Result Cards ---- */
.result-cards {
  display: grid;
  grid-template-columns: 1fr;
  gap: 0.875rem;
  margin-bottom: 1.25rem;
}

.result-card {
  background: var(--surface);
  border-radius: var(--radius);
  padding: 1.25rem;
  box-shadow: var(--shadow);
  border: 1px solid rgba(0,0,0,0.05);
  display: flex;
  align-items: flex-start;
  gap: 1rem;
  transition: box-shadow var(--transition), transform 0.2s ease;
}

.result-card:hover {
  box-shadow: var(--shadow-hover);
  transform: translateY(-2px);
}

.result-card__icon {
  width: 44px;
  height: 44px;
  border-radius: 10px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.375rem;
  flex-shrink: 0;
}

.result-card--primary .result-card__icon {
  background: #dbeafe;
  color: var(--primary);
}

.result-card--green .result-card__icon {
  background: #dcfce7;
  color: var(--green);
}

.result-card--indigo .result-card__icon {
  background: #ede9fe;
  color: var(--indigo);
}

.result-card__body {
  flex: 1;
  min-width: 0;
}

.result-value {
  font-family: 'Outfit', sans-serif;
  font-size: clamp(1.5rem, 5vw, 2.25rem);
  font-weight: 800;
  line-height: 1.1;
  letter-spacing: -0.02em;
}

.result-card--primary .result-value { color: var(--primary); }
.result-card--green .result-value    { color: var(--green); }
.result-card--indigo .result-value   { color: var(--indigo); }

.result-label {
  font-size: 0.8125rem;
  color: var(--text-muted);
  margin-top: 0.25rem;
  font-weight: 600;
}

.result-sub {
  font-size: 0.75rem;
  color: var(--text-weak);
  margin-top: 0.125rem;
}

/* ---- Breakdown Card ---- */
.breakdown-card {
  background: var(--surface);
  border-radius: var(--radius);
  padding: 1.25rem;
  box-shadow: var(--shadow);
  border: 1px solid rgba(0,0,0,0.05);
  margin-bottom: 1.25rem;
}

.breakdown-card h3,
.chart-card h3,
.tax-benefit-card h3 {
  font-size: 0.9375rem;
  font-weight: 700;
  color: var(--text);
  margin-bottom: 1rem;
  display: flex;
  align-items: center;
  gap: 0.4rem;
}

.breakdown-card h3 i { color: var(--primary); }

.breakdown-bar-wrapper {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.breakdown-bar {
  height: 20px;
  border-radius: 100px;
  overflow: hidden;
  background: #e2e8f0;
  display: flex;
}

.bar-principal {
  background: linear-gradient(90deg, var(--primary), #3b82f6);
  height: 100%;
  transition: width 0.5s ease;
  border-radius: 100px 0 0 100px;
}

.bar-gain {
  background: linear-gradient(90deg, #10b981, var(--green));
  height: 100%;
  transition: width 0.5s ease;
  border-radius: 0 100px 100px 0;
}

.breakdown-legend {
  display: flex;
  align-items: center;
  gap: 1rem;
  font-size: 0.8125rem;
  color: var(--text-muted);
  flex-wrap: wrap;
}

.breakdown-legend strong {
  color: var(--text);
  margin-left: 0.25rem;
}

.legend-dot {
  display: inline-block;
  width: 10px;
  height: 10px;
  border-radius: 50%;
}

.legend-dot--blue  { background: var(--primary); }
.legend-dot--green { background: var(--green); }

/* ---- Chart Card ---- */
.chart-card {
  background: var(--surface);
  border-radius: var(--radius);
  padding: 1.25rem;
  box-shadow: var(--shadow);
  border: 1px solid rgba(0,0,0,0.05);
  margin-bottom: 1.25rem;
}

.chart-card h3 i { color: var(--green); }

.chart-wrapper {
  position: relative;
  height: 260px;
}

/* ---- Tax Benefit Card ---- */
.tax-benefit-card {
  background: linear-gradient(135deg, #eff6ff, #f0fdf4);
  border: 1px solid #bfdbfe;
  border-radius: var(--radius);
  padding: 1.25rem;
  margin-bottom: 1.25rem;
}

.tax-benefit-card h3 { color: #1e40af; }
.tax-benefit-card h3 i { color: #1e40af; }

.tax-benefit-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 0.875rem;
}

.tax-benefit-item {
  background: rgba(255,255,255,0.7);
  border-radius: var(--radius-sm);
  padding: 1rem;
  border: 1px solid rgba(29,78,216,0.1);
}

.tax-benefit-label {
  font-size: 0.8125rem;
  font-weight: 700;
  color: #1e40af;
  margin-bottom: 0.25rem;
}

.tax-benefit-value {
  font-family: 'Outfit', sans-serif;
  font-size: 1.375rem;
  font-weight: 800;
  color: var(--primary);
}

.tax-benefit-note {
  font-size: 0.75rem;
  color: var(--text-muted);
  margin-top: 0.25rem;
}

.tax-benefit-disclaimer {
  font-size: 0.75rem;
  color: var(--text-muted);
  margin-top: 0.875rem;
  padding-top: 0.875rem;
  border-top: 1px solid rgba(29,78,216,0.12);
}

/* ---- Howto Section ---- */
.howto-section {
  margin-top: 2rem;
}

.howto-section h2 {
  font-family: 'Outfit', sans-serif;
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--text);
  margin-bottom: 1rem;
  display: flex;
  align-items: center;
  gap: 0.4rem;
}

.howto-section h2 i { color: var(--primary); }

/* ---- Accordion ---- */
.accordion-list {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
  margin-bottom: 1.5rem;
}

.accordion-item {
  background: var(--surface);
  border: 1px solid rgba(0,0,0,0.07);
  border-radius: var(--radius-sm);
  overflow: hidden;
  box-shadow: 0 1px 3px rgba(0,0,0,0.04);
}

.accordion-summary {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  padding: 0.875rem 1rem;
  cursor: pointer;
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--text);
  list-style: none;
  min-height: 52px;
  transition: background var(--transition);
  user-select: none;
}

.accordion-summary::-webkit-details-marker { display: none; }

.accordion-summary::after {
  content: '\F282';
  font-family: 'bootstrap-icons';
  margin-left: auto;
  font-size: 0.875rem;
  color: var(--text-muted);
  transition: transform 0.2s ease;
  flex-shrink: 0;
}

details[open] > .accordion-summary::after {
  transform: rotate(180deg);
}

.accordion-summary:hover {
  background: #f8fafc;
}

.faq-q { color: #1e40af; }
.faq-q::before {
  content: 'Q';
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 24px;
  height: 24px;
  border-radius: 6px;
  background: var(--primary);
  color: #fff;
  font-size: 0.75rem;
  font-weight: 800;
  flex-shrink: 0;
}

.step-num {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 26px;
  height: 26px;
  border-radius: 50%;
  background: var(--primary);
  color: #fff;
  font-size: 0.8125rem;
  font-weight: 700;
  font-family: 'Outfit', sans-serif;
  flex-shrink: 0;
}

.accordion-body {
  padding: 0.75rem 1rem 1rem;
  font-size: 0.875rem;
  color: var(--text-muted);
  line-height: 1.7;
  border-top: 1px solid rgba(0,0,0,0.06);
}

/* ---- About Section ---- */
.about-section {
  background: var(--surface);
  border-radius: var(--radius);
  padding: 1.25rem;
  box-shadow: var(--shadow);
  border: 1px solid rgba(0,0,0,0.05);
  margin-bottom: 1.5rem;
}

.about-section h2 {
  font-size: 1.05rem;
  font-weight: 700;
  color: var(--text);
  margin-bottom: 0.75rem;
}

.about-section p {
  font-size: 0.9rem;
  color: #4b5563;
  line-height: 1.8;
}

/* ---- FAQ Section ---- */
.faq-section h2 {
  font-size: 1.05rem;
}

/* ---- Footer ---- */
footer {
  text-align: center;
  padding: 2rem 1rem;
  font-size: 0.8125rem;
  color: var(--text-muted);
  border-top: 1px solid var(--border);
  margin-top: 2rem;
}

footer a {
  color: var(--primary);
  text-decoration: none;
}

footer a:hover {
  text-decoration: underline;
}

.footer-sep {
  margin: 0 0.5rem;
  opacity: 0.4;
}

footer p + p {
  margin-top: 0.5rem;
}

/* ============================================================
   Responsive — Tablet (640px+)
   ============================================================ */
@media (min-width: 640px) {
  main {
    padding: 1.75rem 1.5rem 2.5rem;
  }

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

  .result-cards {
    grid-template-columns: repeat(3, 1fr);
  }

  .tax-benefit-grid {
    grid-template-columns: 1fr 1fr;
  }

  .chart-wrapper {
    height: 320px;
  }
}

/* ============================================================
   Responsive — Desktop (900px+)
   ============================================================ */
@media (min-width: 900px) {
  main {
    padding: 2rem 2rem 3rem;
  }

  .tool-section {
    padding: 2rem;
  }

  .result-card {
    padding: 1.5rem;
  }
}

/* ---- Slider dynamic gradient update ---- */
input[type="range"] {
  --range-percent: 43%;
}