:root {
  --page-bg: transparent;
  --card-bg: #ffffff;
  --card-border: rgba(15, 23, 42, 0.08);
  --panel-bg: linear-gradient(180deg, rgba(240, 247, 255, 0.95), rgba(255, 255, 255, 0.96));
  --text-strong: #0f172a;
  --text-base: #1e293b;
  --text-muted: #64748b;
  --accent: #2563eb;
  --accent-soft: rgba(37, 99, 235, 0.08);
  --success: #15803d;
  --success-soft: rgba(21, 128, 61, 0.08);
  --shadow: 0 28px 60px rgba(15, 23, 42, 0.12);
  --radius-xl: 24px;
  --radius-lg: 18px;
  --radius-md: 14px;
}

* {
  box-sizing: border-box;
}

html {
  font-size: 16px;
}

body {
  margin: 0;
  min-height: 100vh;
  background: var(--page-bg);
  color: var(--text-base);
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
}

.calculator-shell {
  padding: 16px;
}

.calculator-card {
  width: min(100%, 1040px);
  margin: 0 auto;
  background: var(--panel-bg);
  border: 1px solid var(--card-border);
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow);
  padding: 28px;
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 8px 12px;
  border-radius: 999px;
  background: rgba(15, 23, 42, 0.05);
  color: var(--text-base);
  font-size: 0.82rem;
  font-weight: 700;
  letter-spacing: 0.02em;
  text-transform: uppercase;
}

h1 {
  margin: 16px 0 10px;
  color: var(--text-strong);
  font-size: clamp(2rem, 4vw, 3rem);
  line-height: 1.05;
}

.subhead {
  margin: 0 0 24px;
  max-width: 68ch;
  color: var(--text-muted);
  font-size: 1rem;
  line-height: 1.6;
}

.slider-panel,
.input-card,
.metric-card {
  background: var(--card-bg);
  border: 1px solid var(--card-border);
  border-radius: var(--radius-lg);
}

.slider-panel {
  padding: 20px;
}

.slider-heading-row {
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  gap: 16px;
  align-items: center;
  margin-bottom: 16px;
}

.slider-end {
  color: var(--text-muted);
  font-size: 0.92rem;
  font-weight: 600;
}

.slider-end-right {
  text-align: right;
}

.participation-pill {
  min-width: 88px;
  display: inline-flex;
  justify-content: center;
  padding: 10px 14px;
  border-radius: 999px;
  background: var(--accent-soft);
  color: var(--accent);
  font-size: 1.05rem;
  font-weight: 800;
}

input[type="range"] {
  width: 100%;
  margin: 0;
  accent-color: var(--accent);
  cursor: pointer;
}

.slider-scale {
  display: flex;
  justify-content: space-between;
  margin-top: 10px;
  color: var(--text-muted);
  font-size: 0.86rem;
}

.metric-grid {
  display: grid;
  gap: 16px;
  margin-top: 16px;
}

.metric-grid-top,
.metric-grid-bottom,
.input-grid {
  grid-template-columns: repeat(2, minmax(0, 1fr));
}

.metric-card {
  display: flex;
  flex-direction: column;
  gap: 10px;
  padding: 20px;
}

.metric-card strong {
  color: var(--text-strong);
  font-size: clamp(1.8rem, 3vw, 2.4rem);
  line-height: 1;
}

.metric-card-accent {
  background: linear-gradient(180deg, rgba(37, 99, 235, 0.08), rgba(255, 255, 255, 1));
}

.metric-card-success {
  background: linear-gradient(180deg, rgba(21, 128, 61, 0.08), rgba(255, 255, 255, 1));
}

.metric-label {
  color: var(--text-muted);
  font-size: 0.94rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.03em;
}

.metric-detail {
  color: var(--text-muted);
  font-size: 0.95rem;
}

.input-grid {
  display: grid;
  gap: 16px;
  margin-top: 16px;
}

.input-card {
  display: flex;
  flex-direction: column;
  gap: 12px;
  padding: 20px;
}

.input-label {
  color: var(--text-strong);
  font-size: 1rem;
  font-weight: 700;
}

.input-field {
  display: flex;
  align-items: center;
  border: 1px solid rgba(15, 23, 42, 0.12);
  border-radius: var(--radius-md);
  background: #fff;
  min-height: 58px;
  padding: 0 16px;
}

.input-field:focus-within {
  border-color: rgba(37, 99, 235, 0.45);
  box-shadow: 0 0 0 4px rgba(37, 99, 235, 0.12);
}

.input-field input {
  width: 100%;
  border: 0;
  outline: 0;
  background: transparent;
  color: var(--text-strong);
  font-size: 1.15rem;
  font-weight: 700;
  padding: 16px 0;
  appearance: textfield;
}

.input-field input::-webkit-outer-spin-button,
.input-field input::-webkit-inner-spin-button {
  -webkit-appearance: none;
  margin: 0;
}

.input-prefix,
.input-suffix {
  color: var(--text-muted);
  font-size: 1rem;
  font-weight: 700;
}

.input-prefix {
  margin-right: 10px;
}

.input-suffix {
  margin-left: 10px;
}

.input-help {
  color: var(--text-muted);
  font-size: 0.9rem;
  line-height: 1.5;
}

.summary {
  margin: 20px 0 0;
  padding: 16px 18px;
  background: rgba(15, 23, 42, 0.04);
  border-radius: var(--radius-md);
  color: var(--text-base);
  font-size: 0.98rem;
  line-height: 1.6;
}

.assumption-note {
  margin: 18px 0 0;
  color: var(--text-muted);
  font-size: 0.88rem;
  line-height: 1.7;
}

code {
  font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono", "Courier New", monospace;
  font-size: 0.92em;
  background: rgba(15, 23, 42, 0.05);
  padding: 0.12rem 0.35rem;
  border-radius: 0.35rem;
  color: var(--text-base);
}

.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

@media (max-width: 760px) {
  .calculator-shell {
    padding: 0;
  }

  .calculator-card {
    padding: 20px;
    border-radius: 0;
  }

  .slider-heading-row,
  .metric-grid-top,
  .metric-grid-bottom,
  .input-grid {
    grid-template-columns: 1fr;
  }

  .slider-end-right {
    text-align: left;
  }
}