:root {
  --bg: #fff;
  --text: #111;
  --muted: #666;
  --border: #e0e0e0;
  --accent: #111;
  --ff: system-ui, -apple-system, sans-serif;
  --ff-mono: ui-monospace, "Menlo", monospace;
}

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

body {
  font-family: var(--ff);
  font-size: 1rem;
  background: var(--bg);
  color: var(--text);
  min-height: 100dvh;
  display: grid;
  grid-template-rows: auto 1fr auto;
}

.site-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 1.25rem 2rem;
  border-bottom: 1px solid var(--border);
}

.wordmark {
  font-size: 0.875rem;
  font-weight: 600;
  letter-spacing: 0.02em;
  text-decoration: none;
  color: var(--text);
}

.nav-back {
  font-size: 0.8rem;
  color: var(--muted);
  text-decoration: none;
  transition: color 0.1s;
}

.nav-back:hover {
  color: var(--text);
}

.main {
  padding: 3rem 2rem 4rem;
  margin-inline: auto;
}

.tool-header {
  margin-bottom: 2rem;
}

h1 {
  font-size: 1.5rem;
  font-weight: 600;
  letter-spacing: -0.02em;
  margin-bottom: 0.25rem;
}

.tool-subtitle {
  font-size: 0.875rem;
  color: var(--muted);
}

.field-label {
  display: block;
  font-size: 0.7rem;
  font-weight: 600;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--muted);
  margin-bottom: 0.5rem;
}

input[type="date"],
input[type="number"] {
  font-family: var(--ff-mono);
  font-size: 0.9rem;
  color: var(--text);
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: 3px;
  padding: 0.6rem 0.75rem;
  outline: none;
  width: 100%;
  transition: border-color 0.15s;
}

input[type="date"]:focus,
input[type="number"]:focus {
  border-color: var(--accent);
}

input[type="date"]:focus-visible,
input[type="number"]:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 1px;
}

input[type="number"] {
  -moz-appearance: textfield;
}

input[type="number"]::-webkit-inner-spin-button,
input[type="number"]::-webkit-outer-spin-button {
  -webkit-appearance: none;
  margin: 0;
}

input[type="range"] {
  appearance: none;
  -webkit-appearance: none;
  width: 100%;
  height: 2px;
  border-radius: 999px;
  background: var(--border);
  outline: none;
  margin: 0.625rem 0 0.25rem;
  cursor: pointer;
}

input[type="range"]::-webkit-slider-thumb {
  -webkit-appearance: none;
  appearance: none;
  width: 16px;
  height: 16px;
  border-radius: 50%;
  background: var(--text);
  cursor: pointer;
}

input[type="range"]::-moz-range-thumb {
  width: 16px;
  height: 16px;
  border-radius: 50%;
  background: var(--text);
  border: none;
  cursor: pointer;
}

.site-footer {
  padding: 1.25rem 2rem;
  border-top: 1px solid var(--border);
  font-size: 0.75rem;
  color: var(--muted);
  text-align: center;
}

.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: 640px) {
  .main {
    padding: 2rem 1.25rem 3rem;
  }
}