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

:root {
  --primary: #16a34a;
  --primary-hover: #15803d;
  --primary-light: #f0fdf4;
  --primary-mid: #dcfce7;
  --bg: #f1f5f9;
  --panel-bg: #ffffff;
  --border: #e2e8f0;
  --text: #1e293b;
  --text-muted: #64748b;
  --radius: 12px;
  --shadow: 0 2px 8px rgba(0,0,0,0.08);
  --shadow-md: 0 4px 16px rgba(0,0,0,0.10);
}

html, body {
  font-family: 'Helvetica Neue', Arial, 'Hiragino Kaku Gothic ProN', 'Hiragino Sans', Meiryo, sans-serif;
  font-size: 15px;
  color: var(--text);
  background: var(--bg);
  -webkit-font-smoothing: antialiased;
  line-height: 1.6;
}

/* ============================================================
   Back bar
   ============================================================ */
.flu-back-bar {
  background: var(--primary);
  padding: 8px 16px;
  text-align: left;
}
.flu-back-btn {
  color: #fff;
  text-decoration: none;
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.03em;
}
.flu-back-btn:hover { text-decoration: underline; }

/* ============================================================
   Header
   ============================================================ */
.tool-header {
  background: linear-gradient(135deg, var(--primary) 0%, #15803d 100%);
  color: #fff;
  padding: 2rem 1rem;
  text-align: center;
}
.header-inner {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 1rem;
  max-width: 900px;
  margin: 0 auto;
}
.header-icon {
  font-size: 2.5rem;
  line-height: 1;
}
.tool-header h1 {
  font-size: 1.8rem;
  font-weight: 700;
  margin-bottom: 0.2rem;
}
.header-sub {
  font-size: 0.95rem;
  opacity: 0.9;
}

/* ============================================================
   Main Layout
   ============================================================ */
.main-container {
  max-width: 1000px;
  margin: 2rem auto;
  padding: 0 1rem;
}

.layout-two-col {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1.5rem;
  align-items: start;
}

@media (max-width: 720px) {
  .layout-two-col {
    grid-template-columns: 1fr;
  }
  .tool-header h1 { font-size: 1.4rem; }
  .header-icon { font-size: 2rem; }
}

/* ============================================================
   Card
   ============================================================ */
.card {
  background: var(--panel-bg);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 1.5rem;
}

.section-title {
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--primary);
  margin-bottom: 1.2rem;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}
.icon-circle {
  font-size: 1.1rem;
}

/* ============================================================
   Form
   ============================================================ */
.form-group {
  margin-bottom: 1.1rem;
}
.form-group label {
  display: block;
  font-weight: 600;
  margin-bottom: 0.35rem;
  font-size: 0.9rem;
  color: var(--text);
}
.required {
  background: #dc2626;
  color: #fff;
  font-size: 0.7rem;
  padding: 1px 6px;
  border-radius: 4px;
  margin-left: 6px;
  vertical-align: middle;
  font-weight: 700;
}
.input-with-unit {
  display: flex;
  align-items: center;
  gap: 0;
  border: 1.5px solid var(--border);
  border-radius: 8px;
  overflow: hidden;
  transition: border-color 0.2s;
}
.input-with-unit:focus-within {
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(22,163,74,0.15);
}
.input-with-unit input {
  border: none;
  outline: none;
  padding: 0.55rem 0.75rem;
  font-size: 1rem;
  flex: 1;
  color: var(--text);
  background: #fff;
  min-width: 0;
}
.unit {
  background: #f8fafc;
  border-left: 1.5px solid var(--border);
  padding: 0.55rem 0.75rem;
  font-size: 0.9rem;
  color: var(--text-muted);
  white-space: nowrap;
}
select {
  width: 100%;
  padding: 0.55rem 0.75rem;
  border: 1.5px solid var(--border);
  border-radius: 8px;
  font-size: 0.95rem;
  color: var(--text);
  background: #fff;
  outline: none;
  cursor: pointer;
  transition: border-color 0.2s;
}
select:focus {
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(22,163,74,0.15);
}
.hint {
  font-size: 0.78rem;
  color: var(--text-muted);
  margin-top: 0.25rem;
}

.btn-calc {
  width: 100%;
  padding: 0.85rem;
  background: var(--primary);
  color: #fff;
  border: none;
  border-radius: 8px;
  font-size: 1.1rem;
  font-weight: 700;
  cursor: pointer;
  margin-top: 0.5rem;
  transition: background 0.2s, transform 0.1s;
  letter-spacing: 0.05em;
}
.btn-calc:hover {
  background: var(--primary-hover);
  transform: translateY(-1px);
}
.btn-calc:active { transform: translateY(0); }

/* ============================================================
   Result
   ============================================================ */
.result-placeholder {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  min-height: 300px;
  color: var(--text-muted);
  text-align: center;
  gap: 1rem;
}
.placeholder-icon { font-size: 3rem; }

/* Hero amount */
.result-hero {
  background: linear-gradient(135deg, var(--primary) 0%, #15803d 100%);
  color: #fff;
  border-radius: 10px;
  padding: 1.2rem 1rem;
  text-align: center;
  margin-bottom: 1rem;
}
.hero-label {
  font-size: 0.85rem;
  opacity: 0.9;
  margin-bottom: 0.3rem;
}
.hero-amount {
  font-size: 2.2rem;
  font-weight: 800;
  letter-spacing: -0.02em;
}

/* Summary grid */
.result-summary-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 0.75rem;
  margin-bottom: 1.2rem;
}
.summary-item {
  background: var(--primary-light);
  border: 1px solid var(--primary-mid);
  border-radius: 8px;
  padding: 0.75rem;
  text-align: center;
}
.summary-label {
  font-size: 0.78rem;
  color: var(--primary);
  margin-bottom: 0.3rem;
  font-weight: 600;
}
.summary-value {
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--primary);
}

/* Table */
.table-title {
  font-size: 0.9rem;
  font-weight: 700;
  color: var(--text);
  margin: 1rem 0 0.5rem;
  padding-left: 0.5rem;
  border-left: 3px solid var(--primary);
}
.breakdown-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.88rem;
  margin-bottom: 0.5rem;
}
.breakdown-table th {
  background: var(--primary);
  color: #fff;
  padding: 0.5rem 0.75rem;
  text-align: left;
  font-weight: 600;
}
.breakdown-table th:last-child,
.breakdown-table td:last-child {
  text-align: right;
}
.breakdown-table td {
  padding: 0.45rem 0.75rem;
  border-bottom: 1px solid #f0f0f0;
  color: var(--text);
}
.breakdown-table tr:last-child td {
  border-bottom: none;
}
.breakdown-table tr:nth-child(even) td {
  background: #fafafa;
}
.breakdown-table .row-total td {
  background: var(--primary-light);
  font-weight: 700;
  color: var(--primary);
  border-top: 2px solid var(--primary-mid);
}
.breakdown-table .row-deduct td {
  color: #dc2626;
}
.breakdown-table .row-net td {
  background: var(--primary-light);
  font-weight: 700;
  color: var(--primary);
}

/* Notice */
.notice-box {
  background: #fffbeb;
  border: 1px solid #fcd34d;
  border-radius: 8px;
  padding: 0.9rem 1rem;
  font-size: 0.8rem;
  color: #92400e;
  margin-top: 1rem;
}
.notice-box strong {
  display: block;
  margin-bottom: 0.4rem;
}
.notice-box ul {
  padding-left: 1.2rem;
}
.notice-box li {
  margin-bottom: 0.2rem;
}

/* ============================================================
   Related Tools
   ============================================================ */
.related-tools {
  margin: 3rem auto;
  padding: 1.5rem;
  max-width: 900px;
  background: #fff;
  border-radius: 12px;
  box-shadow: 0 2px 8px rgba(0,0,0,0.08);
  text-align: center;
}
.related-tools h2 {
  font-size: 1.4rem;
  margin-bottom: 0.8rem;
  color: var(--primary);
}
.related-tools p {
  color: #555;
  margin-bottom: 1rem;
}
.tool-links {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 1rem;
  margin-bottom: 1rem;
}
.tool-card {
  display: inline-block;
  padding: 0.8rem 1.2rem;
  background: var(--primary-light);
  border: 1px solid var(--primary);
  border-radius: 10px;
  text-decoration: none;
  color: var(--primary);
  font-weight: 500;
  transition: all 0.2s;
}
.tool-card:hover {
  background: var(--primary);
  color: #fff;
  transform: translateY(-2px);
}
.more-tools {
  font-size: 0.9rem;
}
.more-tools a {
  color: var(--primary);
  font-weight: 600;
  text-decoration: none;
}
.more-tools a:hover { text-decoration: underline; }

/* ============================================================
   Footer
   ============================================================ */
footer {
  text-align: center;
  padding: 1.5rem 0;
  background-color: #f1f5f9;
  color: #555;
  font-size: 0.9rem;
  border-top: 1px solid #e2e8f0;
  margin-top: 2rem;
}
.footer-nav a {
  color: var(--primary);
  text-decoration: none;
  margin: 0 0.5rem;
}
.footer-nav a:hover { text-decoration: underline; }