/* US QuickCalc - Pure Standalone Stylesheet */
:root {
  --bg: #0f172a;
  --card-bg: #020617;
  --card-border: #1e293b;
  --accent: #10b981;
  --accent-hover: #059669;
  --accent-light: rgba(16, 185, 129, 0.15);
  --text: #f8fafc;
  --text-muted: #94a3b8;
  --text-dim: #64748b;
  --font-sans: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  --font-mono: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, monospace;
}

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

body {
  background-color: var(--bg);
  color: var(--text);
  font-family: var(--font-sans);
  line-height: 1.5;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}
nav a{
  margin:5px;
}

.container {
  width: 100%;
  max-width: 1020px;
  margin: 0 auto;
  padding: 0 10px;
}

/* Header */
.header {
  position: sticky;
  top: 0;
  z-index: 100;
  background-color: rgba(2, 6, 23, 0.95);
  border-bottom: 1px solid var(--card-border);
  backdrop-filter: blur(8px);
}

.header-container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
}
.nav-tabs {
  display: flex;
  gap: 0.35rem;
}

.tab-btn {
  background: transparent;
  border: 1px solid transparent;
  color: var(--text-muted);
  padding: 0.45rem 0.85rem;
  font-size: 0.8rem;
  font-weight: 600;
  border-radius: 8px;
  cursor: pointer;
  transition: all 0.2s ease;
}

.tab-btn:hover {
  color: var(--text);
  background: rgba(30, 41, 59, 0.6);
}

.tab-btn.active {
  background: var(--accent-light);
  color: #6ee7b7;
  border-color: rgba(16, 185, 129, 0.4);
}

.header-badge {
  font-size: 0.75rem;
  color: var(--accent);
  background: var(--accent-light);
  border: 1px solid rgba(16, 185, 129, 0.25);
  padding: 0.25rem 0.65rem;
  border-radius: 9999px;
  font-weight: 500;
}

/* Main */
.main-content {
  flex: 1;
  padding-top: 2rem;
  padding-bottom: 3rem;
}

.section-title {
  text-align: center;
  margin-bottom: 1.5rem;
}

.section-title h1 {
  font-size: 1.75rem;
  font-weight: 800;
  letter-spacing: -0.02em;
}

.section-title p {
  font-size: 0.875rem;
  color: var(--text-muted);
  margin-top: 0.35rem;
}

/* Tabs */
.tab-pane {
  display: none;
}

.tab-pane.active {
  display: block;
}

/* Mode toggles */
.mode-toggle {
  display: flex;
  justify-content: center;
  margin-bottom: 1.5rem;
}

.mode-btn {
  background: var(--card-bg);
  border: 1px solid var(--card-border);
  color: var(--text-muted);
  padding: 0.45rem 1.25rem;
  font-size: 0.8rem;
  font-weight: 600;
  cursor: pointer;
}

.mode-btn:first-child {
  border-radius: 8px 0 0 8px;
}

.mode-btn:last-child {
  border-radius: 0 8px 8px 0;
  border-left: none;
}

.mode-btn.active {
  background: var(--accent);
  color: #020617;
  border-color: var(--accent);
}

/* Grid & Cards */
.calc-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1.5rem;
}

.card {
  background: rgba(2, 6, 23, 0.7);
  border: 1px solid var(--card-border);
  border-radius: 16px;
  padding: 1.5rem;
}

.result-card {
  border-color: rgba(16, 185, 129, 0.35);
  background: linear-gradient(180deg, rgba(2, 6, 23, 0.9) 0%, rgba(6, 78, 59, 0.15) 100%);
  display: flex;
  flex-direction: column;
  justify-content: space-between;
}

/* Forms */
.form-group {
  margin-bottom: 1.15rem;
}

.form-group label {
  display: block;
  font-size: 0.78rem;
  font-weight: 600;
  color: var(--text-muted);
  margin-bottom: 0.35rem;
}

input[type="number"], select {
  width: 100%;
  background: #0f172a;
  border: 1px solid #334155;
  color: var(--text);
  padding: 0.65rem 0.85rem;
  border-radius: 10px;
  font-size: 1rem;
  font-family: var(--font-mono);
  font-weight: 600;
}

input:focus, select:focus {
  outline: none;
  border-color: var(--accent);
}

.input-prefix-wrapper {
  position: relative;
  display: flex;
  align-items: center;
}

.input-prefix-wrapper .prefix {
  position: absolute;
  left: 0.85rem;
  color: var(--text-dim);
  font-family: var(--font-mono);
  font-weight: 700;
}

.input-prefix-wrapper input {
  padding-left: 2rem;
}

.pill-group {
  display: flex;
  gap: 0.4rem;
  margin-top: 0.5rem;
  flex-wrap: wrap;
}

.pill-btn {
  background: #0f172a;
  border: 1px solid var(--card-border);
  color: var(--text-muted);
  padding: 0.25rem 0.65rem;
  border-radius: 6px;
  font-size: 0.72rem;
  font-family: var(--font-mono);
  cursor: pointer;
}

.pill-btn.active, .pill-btn:hover {
  background: var(--accent-light);
  color: #6ee7b7;
  border-color: rgba(16, 185, 129, 0.4);
}

.btn-grid-4, .btn-grid-6, .btn-grid-5 {
  display: grid;
  gap: 0.4rem;
}

.btn-grid-4 { grid-template-columns: repeat(4, 1fr); }
.btn-grid-5 { grid-template-columns: repeat(5, 1fr); }
.btn-grid-6 { grid-template-columns: repeat(6, 1fr); }

.tip-rate-btn, .split-btn, .disc-btn, .gas-split-btn {
  background: #0f172a;
  border: 1px solid var(--card-border);
  color: var(--text);
  padding: 0.5rem;
  border-radius: 8px;
  font-size: 0.78rem;
  font-family: var(--font-mono);
  font-weight: 700;
  cursor: pointer;
}

.tip-rate-btn.active, .split-btn.active, .disc-btn.active, .gas-split-btn.active {
  background: var(--accent);
  color: #020617;
  border-color: var(--accent);
}

.inline-input {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  margin-top: 0.6rem;
  font-size: 0.78rem;
  color: var(--text-muted);
}

.inline-input input {
  width: 75px;
  padding: 0.25rem 0.5rem;
  font-size: 0.8rem;
}

.checkbox-row {
  margin-top: 0.5rem;
  font-size: 0.78rem;
  color: var(--text-muted);
}

.subtext {
  font-size: 0.7rem;
  color: var(--text-dim);
  display: block;
  margin-top: 0.25rem;
}

.grid-2 {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 0.75rem;
}

/* Result Box */
.result-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.badge-title {
  font-size: 0.75rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--accent);
}

.copy-btn {
  background: #0f172a;
  border: 1px solid #334155;
  color: var(--text-muted);
  padding: 0.3rem 0.65rem;
  border-radius: 6px;
  font-size: 0.72rem;
  cursor: pointer;
}

.copy-btn:hover {
  color: var(--text);
  border-color: var(--accent);
}

.headline-box {
  background: rgba(15, 23, 42, 0.8);
  border: 1px solid var(--card-border);
  border-radius: 12px;
  padding: 1.25rem;
  margin: 1rem 0;
  text-align: center;
}

.headline-label {
  font-size: 0.75rem;
  color: var(--text-muted);
  text-transform: uppercase;
  font-weight: 600;
}

.headline-val {
  font-size: 2.5rem;
  font-weight: 900;
  font-family: var(--font-mono);
  color: var(--accent);
  line-height: 1.1;
  margin: 0.25rem 0;
}

.headline-sub {
  font-size: 0.7rem;
  color: var(--text-dim);
}

.mini-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 0.65rem;
  margin-bottom: 1rem;
}

.mini-card {
  background: rgba(15, 23, 42, 0.6);
  border: 1px solid var(--card-border);
  border-radius: 10px;
  padding: 0.75rem;
}

.mini-label {
  font-size: 0.7rem;
  color: var(--text-dim);
  display: block;
}

.mini-val {
  font-size: 1.15rem;
  font-weight: 700;
  font-family: var(--font-mono);
}

.breakdown-list {
  border-top: 1px solid var(--card-border);
  padding-top: 0.75rem;
  font-size: 0.78rem;
}

.breakdown-row {
  display: flex;
  justify-content: space-between;
  padding: 0.25rem 0;
  color: var(--text-muted);
}

.breakdown-row.sub {
  font-size: 0.72rem;
  color: var(--text-dim);
}

.breakdown-row.total {
  border-top: 1px solid var(--card-border);
  margin-top: 0.5rem;
  padding-top: 0.5rem;
  font-weight: 700;
  color: var(--text);
  font-size: 0.85rem;
}

.deduct { color: #f87171; font-family: var(--font-mono); }
.highlight { color: var(--accent); font-family: var(--font-mono); }

.info-note {
  background: #0f172a;
  border: 1px solid var(--card-border);
  border-radius: 8px;
  padding: 0.65rem;
  font-size: 0.7rem;
  color: var(--text-dim);
  margin-top: 1rem;
}

/* Bottom switcher */
.bottom-switcher {
  margin-top: 2.5rem;
  border-top: 1px solid var(--card-border);
  padding-top: 1.5rem;
  text-align: center;
}

.bottom-switcher h4 {
  font-size: 0.75rem;
  text-transform: uppercase;
  color: var(--text-dim);
  letter-spacing: 0.05em;
  margin-bottom: 0.85rem;
}

.switcher-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 0.75rem;
}

.switch-card {
  background: rgba(2, 6, 23, 0.6);
  border: 1px solid var(--card-border);
  border-radius: 12px;
  padding: 0.85rem;
  text-align: left;
  cursor: pointer;
  color: var(--text);
  transition: all 0.2s;
}

.switch-card:hover {
  border-color: var(--accent);
  background: var(--card-bg);
}

.switch-card strong {
  display: block;
  font-size: 0.85rem;
  color: var(--accent);
}

.switch-card span {
  font-size: 0.7rem;
  color: var(--text-dim);
  margin-top: 0.2rem;
  display: block;
}

/* Footer */
.footer {
  border-top: 1px solid var(--card-border);
  background: var(--card-bg);
  padding: 1.25rem 0;
  font-size: 0.75rem;
  color: var(--text-dim);
}

.footer-container {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.footer-links button {
  background: none;
  border: none;
  color: var(--text-dim);
  margin-left: 0.85rem;
  cursor: pointer;
}

.footer-links button:hover {
  color: var(--text);
}

.hidden { display: none !important; }

/* Responsive */
@media (max-width: 768px) {
  .calc-grid {
    grid-template-columns: 1fr;
  }
  .switcher-grid {
    grid-template-columns: 1fr 1fr;
  }
  .header-badge {
    display: none;
  }
}