:root {
  --bg-deep: #090d16;
  --bg-card: #111827;
  --bg-card-inner: #1a2234;
  --border-subtle: rgba(255, 255, 255, 0.08);
  --border-strong: rgba(255, 255, 255, 0.16);
  --accent: #38bdf8;
  --accent-hover: #0284c7;
  --accent-dim: rgba(56, 189, 248, 0.12);
  --text-main: #f8fafc;
  --text-muted: #94a3b8;
  --text-dim: #64748b;
  --success: #10b981;
  --warn: #f59e0b;
  --font-heading: 'Bricolage Grotesque', -apple-system, BlinkMacSystemFont, sans-serif;
  --font-mono: 'JetBrains Mono', monospace;
  --radius-sm: 6px;
  --radius-md: 10px;
  --radius-lg: 14px;
}

* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

body {
  background-color: var(--bg-deep);
  color: var(--text-main);
  font-family: var(--font-mono);
  min-height: 100vh;
  padding: clamp(1rem, 3vw, 2.5rem) 1rem;
  line-height: 1.5;
}

.container {
  max-width: 900px;
  margin: 0 auto;
}

.backlink-bar {
  margin-bottom: 1.5rem;
}

.backlink {
  color: var(--text-muted);
  text-decoration: none;
  font-size: 0.85rem;
  transition: color 0.15s ease;
}

.backlink:hover {
  color: var(--accent);
}

header {
  text-align: center;
  margin-bottom: 2rem;
}

.badge {
  display: inline-block;
  background: var(--accent-dim);
  border: 1px solid var(--accent);
  color: var(--accent);
  padding: 0.3rem 0.85rem;
  border-radius: 9999px;
  font-size: 0.75rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  margin-bottom: 0.85rem;
}

h1 {
  font-family: var(--font-heading);
  font-size: clamp(1.8rem, 4vw, 2.6rem);
  font-weight: 800;
  color: var(--text-main);
  letter-spacing: -0.02em;
  line-height: 1.2;
  margin-bottom: 0.75rem;
}

.subtitle {
  color: var(--text-muted);
  font-size: 0.95rem;
  max-width: 650px;
  margin: 0 auto;
  line-height: 1.6;
}

/* Preset Chips */
.presets-section {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.5rem;
  margin-bottom: 1.5rem;
  padding: 0.75rem 1rem;
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
}

.presets-label {
  font-size: 0.8rem;
  color: var(--text-muted);
  font-weight: 600;
  margin-right: 0.25rem;
}

.preset-chip {
  background: var(--bg-card-inner);
  border: 1px solid var(--border-subtle);
  color: var(--text-main);
  padding: 0.35rem 0.75rem;
  border-radius: var(--radius-sm);
  font-family: var(--font-mono);
  font-size: 0.78rem;
  cursor: pointer;
  transition: all 0.15s ease;
}

.preset-chip:hover {
  border-color: var(--accent);
  color: var(--accent);
  background: var(--accent-dim);
}

/* Card */
.card {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  padding: clamp(1.2rem, 3vw, 1.8rem);
  margin-bottom: 1.5rem;
}

.card h2 {
  font-family: var(--font-heading);
  font-size: 1.3rem;
  color: var(--text-main);
  margin-bottom: 0.4rem;
}

.card-desc {
  font-size: 0.85rem;
  color: var(--text-muted);
  margin-bottom: 1.2rem;
}

/* Form controls */
.grid-form {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 1.2rem;
  margin-bottom: 1.2rem;
}

.form-group {
  display: flex;
  flex-direction: column;
  gap: 0.4rem;
}

.form-group label {
  font-size: 0.82rem;
  font-weight: 600;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

select, input[type="number"], input[type="text"] {
  background: var(--bg-card-inner);
  border: 1px solid var(--border-strong);
  border-radius: var(--radius-sm);
  color: var(--text-main);
  font-family: var(--font-mono);
  font-size: 1rem;
  padding: 0.65rem 0.85rem;
  outline: none;
  transition: border-color 0.15s ease;
  width: 100%;
}

select:focus, input:focus {
  border-color: var(--accent);
  box-shadow: 0 0 0 2px var(--accent-dim);
}

/* Switch & checkboxes */
.checkbox-row {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  margin-top: 0.6rem;
  cursor: pointer;
  user-select: none;
}

.checkbox-row input[type="checkbox"] {
  width: 18px;
  height: 18px;
  accent-color: var(--accent);
  cursor: pointer;
}

.checkbox-label {
  font-size: 0.85rem;
  color: var(--text-main);
}

/* Result Box */
.result-box {
  background: var(--bg-card-inner);
  border: 1px solid var(--accent);
  border-radius: var(--radius-md);
  padding: 1.4rem;
  margin-top: 1.2rem;
  text-align: center;
}

.result-main {
  font-family: var(--font-heading);
  font-size: clamp(2.2rem, 5vw, 3.2rem);
  font-weight: 800;
  color: var(--accent);
  margin-bottom: 0.4rem;
}

.result-secondary {
  font-size: 0.88rem;
  color: var(--text-muted);
  line-height: 1.6;
}

/* Breakdown table */
.breakdown-table {
  width: 100%;
  border-collapse: collapse;
  margin-top: 1.2rem;
  font-size: 0.85rem;
  text-align: left;
}

.breakdown-table td {
  padding: 0.6rem 0.75rem;
  border-bottom: 1px solid var(--border-subtle);
}

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

.breakdown-table .item-name {
  color: var(--text-main);
}

.breakdown-table .item-sub {
  display: block;
  font-size: 0.72rem;
  color: var(--text-dim);
}

.breakdown-table .item-val {
  text-align: right;
  font-weight: 700;
  color: var(--text-main);
}

.breakdown-table .total-row td {
  border-top: 2px solid var(--accent);
  font-weight: 800;
  color: var(--accent);
  font-size: 1.05rem;
}

/* Split party box */
.split-box {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 0.75rem;
  margin-top: 1.2rem;
}

.split-card {
  background: rgba(255, 255, 255, 0.03);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-sm);
  padding: 0.85rem;
  text-align: center;
}

.split-title {
  font-size: 0.75rem;
  color: var(--text-muted);
  text-transform: uppercase;
}

.split-amount {
  font-size: 1.25rem;
  font-weight: 800;
  color: var(--text-main);
  margin-top: 0.2rem;
}

/* Buttons */
.btn-action {
  width: 100%;
  background: var(--bg-card-inner);
  border: 1px solid var(--border-strong);
  color: var(--text-main);
  font-family: var(--font-mono);
  font-size: 0.85rem;
  font-weight: 600;
  padding: 0.65rem 1rem;
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: all 0.15s ease;
  margin-top: 0.85rem;
}

.btn-action:hover {
  background: var(--accent-dim);
  border-color: var(--accent);
  color: var(--accent);
}

/* Tables */
.table-wrap {
  overflow-x: auto;
  margin: 1rem 0 0.5rem;
}

table.ref-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.84rem;
  font-family: var(--font-mono);
  text-align: left;
  border: 1px solid var(--border-subtle);
}

table.ref-table th {
  background: var(--bg-card-inner);
  border-bottom: 1px solid var(--border-strong);
  color: var(--accent);
  padding: 0.65rem 0.85rem;
  font-weight: 700;
}

table.ref-table td {
  padding: 0.55rem 0.85rem;
  border-bottom: 1px solid var(--border-subtle);
  color: var(--text-muted);
}

table.ref-table tr:hover td {
  background: rgba(255, 255, 255, 0.02);
  color: var(--text-main);
}

/* Accordion FAQ */
.faq-item {
  border-bottom: 1px solid var(--border-subtle);
  padding: 0.85rem 0;
}

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

.faq-item summary {
  cursor: pointer;
  font-weight: 600;
  font-size: 0.95rem;
  color: var(--text-main);
  list-style: none;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

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

.faq-item summary::after {
  content: "+";
  color: var(--accent);
  font-size: 1.2rem;
  font-weight: 700;
}

.faq-item[open] summary::after {
  content: "−";
}

.faq-item p {
  margin-top: 0.6rem;
  font-size: 0.85rem;
  color: var(--text-muted);
  line-height: 1.6;
}

/* Family nav */
.family-nav {
  margin: 32px auto 20px;
  padding: 20px 16px;
  border-top: 1px solid var(--border-subtle);
}

.family-pill {
  padding: 6px 12px;
  border-radius: 6px;
  font-size: 0.82rem;
  text-decoration: none;
  color: inherit;
  background: rgba(125,125,125,0.08);
  border: 1px solid rgba(125,125,125,0.2);
  transition: all 0.2s;
}

.family-pill.active {
  background: var(--accent-dim);
  border-color: var(--accent);
  color: var(--accent);
  font-weight: 700;
}

footer {
  text-align: center;
  color: var(--text-dim);
  font-size: 0.78rem;
  padding-top: 2rem;
  border-top: 1px solid var(--border-subtle);
}

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