/* =============================================
   GoFinSim 源泉徴収税額シミュレーター
   style.css
   フォント：Noto Sans CJK JP（ローカル指定）
   ============================================= */

/* リセット・ベース */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

:root {
  --color-main:       #1e3a5f;
  --color-main-light: #2d6a9f;
  --color-withhold:   #dc2626;
  --color-net:        #1d4ed8;
  --color-error:      #dc2626;
  --color-note:       #6b7280;
  --color-border:     #e2e8f0;
  --color-bg:         #f8fafc;
  --color-white:      #ffffff;
  --color-text:       #1f2937;
  --radius-card:      12px;
  --radius-btn:       8px;
  --shadow-card:      0 2px 12px rgba(0,0,0,0.07);
  --font-base:        'Noto Sans CJK JP', 'Noto Sans JP', 'Hiragino Kaku Gothic ProN', Meiryo, sans-serif;
}

html {
  font-size: 16px;
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: var(--font-base);
  background: var(--color-bg);
  color: var(--color-text);
  line-height: 1.7;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

/* =============================================
   ヘッダー
   ============================================= */
.site-header {
  background: var(--color-main);
  padding: 0 20px;
  height: 56px;
  display: flex;
  align-items: center;
}

.header-logo {
  display: flex;
  align-items: center;
  gap: 10px;
  text-decoration: none;
  color: var(--color-white);
}

.logo-mark {
  width: 32px;
  height: 32px;
  background: rgba(255,255,255,0.15);
  border: 1.5px solid rgba(255,255,255,0.35);
  border-radius: 8px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 16px;
  font-weight: 900;
  letter-spacing: -0.02em;
  flex-shrink: 0;
}

.logo-text {
  font-size: 17px;
  font-weight: 700;
  letter-spacing: 0.04em;
}

/* =============================================
   メインレイアウト
   ============================================= */
.main-wrap {
  flex: 1;
  width: 100%;
  max-width: 680px;
  margin: 0 auto;
  padding: 32px 16px 48px;
  display: flex;
  flex-direction: column;
  gap: 20px;
}

/* =============================================
   ツールヘッダー
   ============================================= */
.tool-header {
  text-align: center;
  padding: 4px 0 8px;
}

.tool-title {
  font-size: 22px;
  font-weight: 900;
  color: var(--color-main);
  letter-spacing: 0.02em;
  margin-bottom: 6px;
  line-height: 1.35;
}

.tool-subtitle {
  font-size: 14px;
  color: var(--color-note);
  margin-bottom: 10px;
}

.disclaimer-inline {
  font-size: 12px;
  color: var(--color-note);
  background: #fff8e1;
  border: 1px solid #fde68a;
  border-radius: 6px;
  padding: 8px 14px;
  text-align: center;
  line-height: 1.6;
}

/* =============================================
   カード
   ============================================= */
.card {
  background: var(--color-white);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-card);
  padding: 28px 28px 32px;
  box-shadow: var(--shadow-card);
}

/* =============================================
   フィールド
   ============================================= */
.field-group {
  margin-bottom: 24px;
}

.field-label {
  display: block;
  font-size: 14px;
  font-weight: 700;
  color: var(--color-main);
  margin-bottom: 10px;
}

/* 入力補足注記 */
.input-note {
  font-size: 12px;
  color: var(--color-note);
  margin-bottom: 10px;
  line-height: 1.6;
}

/* テキスト入力 */
.input-wrap {
  display: flex;
  align-items: center;
  gap: 0;
  border: 1.5px solid var(--color-border);
  border-radius: 8px;
  background: var(--color-white);
  overflow: hidden;
  transition: border-color 0.15s, box-shadow 0.15s;
}

.input-wrap:focus-within {
  border-color: var(--color-main-light);
  box-shadow: 0 0 0 3px rgba(45,106,159,0.12);
}

#invoice-amount {
  flex: 1;
  font-family: var(--font-base);
  font-size: 18px;
  font-weight: 700;
  color: var(--color-text);
  border: none;
  outline: none;
  padding: 14px 16px;
  background: transparent;
  min-height: 52px;
  -webkit-appearance: none;
}

#invoice-amount::placeholder {
  font-weight: 400;
  color: #cbd5e1;
  font-size: 15px;
}

.input-unit {
  font-size: 15px;
  font-weight: 700;
  color: var(--color-note);
  padding: 0 16px 0 4px;
  flex-shrink: 0;
}

/* エラーメッセージ */
.error-message {
  font-size: 13px;
  color: var(--color-error);
  margin-top: 6px;
  min-height: 18px;
  line-height: 1.4;
}

/* 計算ボタン */
.calc-btn {
  width: 100%;
  background: var(--color-main);
  color: var(--color-white);
  font-family: var(--font-base);
  font-size: 16px;
  font-weight: 700;
  border: none;
  border-radius: var(--radius-btn);
  padding: 16px;
  cursor: pointer;
  letter-spacing: 0.06em;
  min-height: 52px;
  transition: background 0.15s, transform 0.1s;
  -webkit-tap-highlight-color: transparent;
}

.calc-btn:hover {
  background: var(--color-main-light);
}

.calc-btn:active {
  transform: scale(0.98);
}

/* =============================================
   結果エリア
   ============================================= */
.result-card {
  display: none;
  text-align: center;
}

.result-card.is-visible {
  display: block;
}

.result-label {
  font-size: 13px;
  font-weight: 700;
  color: var(--color-note);
  letter-spacing: 0.08em;
  margin-bottom: 6px;
}

.result-value {
  font-size: 40px;
  font-weight: 900;
  letter-spacing: -0.01em;
  line-height: 1.1;
  margin-bottom: 4px;
}

.result-value::after {
  content: ' 円';
  font-size: 18px;
  font-weight: 700;
}

.result-value.withholding {
  color: var(--color-withhold);
}

.result-value.net-amount {
  color: var(--color-net);
}

.result-divider {
  height: 1px;
  background: var(--color-border);
  margin: 20px 0;
}

.result-rate {
  font-size: 13px;
  color: var(--color-note);
  margin-top: 12px;
  line-height: 1.6;
}

.result-breakdown {
  font-size: 12px;
  color: var(--color-note);
  margin-top: 4px;
  line-height: 1.6;
}

.recalc-btn {
  display: inline-block;
  margin-top: 20px;
  background: none;
  border: 1.5px solid var(--color-border);
  border-radius: var(--radius-btn);
  font-family: var(--font-base);
  font-size: 14px;
  font-weight: 700;
  color: var(--color-note);
  padding: 10px 24px;
  cursor: pointer;
  min-height: 44px;
  transition: border-color 0.15s, color 0.15s;
  -webkit-tap-highlight-color: transparent;
}

.recalc-btn:hover {
  border-color: var(--color-main);
  color: var(--color-main);
}

/* =============================================
   注記エリア
   ============================================= */
.notes-area {
  background: var(--color-white);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-card);
  padding: 20px 24px;
}

.notes-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.notes-list li {
  font-size: 12px;
  color: var(--color-note);
  line-height: 1.65;
  padding-left: 16px;
  position: relative;
}

.notes-list li::before {
  content: '・';
  position: absolute;
  left: 0;
  color: var(--color-note);
}

/* =============================================
   アコーディオン
   ============================================= */
.accordion-wrap {
  background: var(--color-white);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-card);
  overflow: hidden;
}

.accordion-title {
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 14px;
  font-weight: 700;
  color: var(--color-main);
  padding: 18px 24px;
  cursor: pointer;
  list-style: none;
  min-height: 56px;
  -webkit-tap-highlight-color: transparent;
}

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

.accordion-title::after {
  content: '▼';
  font-size: 11px;
  color: var(--color-note);
  transition: transform 0.2s;
  flex-shrink: 0;
  margin-left: 8px;
}

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

.accordion-body {
  padding: 0 24px 20px;
  border-top: 1px solid var(--color-border);
}

.rate-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 13px;
  margin: 16px 0 12px;
}

.rate-table th {
  background: var(--color-main);
  color: var(--color-white);
  font-weight: 700;
  padding: 10px 12px;
  text-align: left;
  font-size: 12px;
}

.rate-table td {
  padding: 10px 12px;
  border-bottom: 1px solid var(--color-border);
  font-size: 13px;
  color: var(--color-text);
  vertical-align: middle;
}

.rate-table tr:last-child td {
  border-bottom: none;
}

.rate-table tr:nth-child(even) td {
  background: #f8fafc;
}

.rate-value {
  font-weight: 900;
  color: var(--color-main);
  white-space: nowrap;
}

.accordion-note {
  font-size: 12px;
  color: var(--color-note);
  margin-top: 8px;
  line-height: 1.6;
}

.accordion-note a {
  color: var(--color-main-light);
  text-decoration: underline;
}

/* =============================================
   フッター
   ============================================= */
.site-footer {
  background: var(--color-main);
  padding: 24px 20px;
  text-align: center;
}

.footer-nav {
  display: flex;
  justify-content: center;
  flex-wrap: wrap;
  gap: 8px 24px;
  margin-bottom: 12px;
}

.footer-nav a {
  font-size: 13px;
  color: rgba(255,255,255,0.70);
  text-decoration: none;
  transition: color 0.15s;
}

.footer-nav a:hover {
  color: var(--color-white);
}

.footer-copy {
  font-size: 12px;
  color: rgba(255,255,255,0.40);
}

/* =============================================
   レスポンシブ（スマホ対応）
   ============================================= */
@media (max-width: 600px) {
  .main-wrap {
    padding: 20px 12px 40px;
    gap: 16px;
  }

  .tool-title {
    font-size: 19px;
  }

  .card {
    padding: 20px 16px 24px;
  }

  #invoice-amount {
    font-size: 16px; /* iOS自動ズーム防止：16px以上必須 */
  }

  .result-value {
    font-size: 34px;
  }

  .result-value::after {
    font-size: 16px;
  }

  .rate-table {
    font-size: 12px;
  }

  .rate-table th,
  .rate-table td {
    padding: 8px 8px;
  }

  .accordion-title {
    padding: 16px 16px;
    font-size: 13px;
  }

  .accordion-body {
    padding: 0 16px 16px;
  }

  .notes-area {
    padding: 16px 16px;
  }
}