:root {
  --accent: #c62828;
  --accent-wash: #fdf3f3;
  --ink: #1b1b1b;
  --muted: #5f6368;
  --line: #dcdfe3;
  --surface: #f7f7f8;
  --sans:
    system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial,
    "Noto Sans Arabic", "Segoe UI Arabic", sans-serif;
  --mono:
    ui-monospace, SFMono-Regular, "SF Mono", Menlo, Consolas, "Liberation Mono",
    monospace;
}

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

[hidden] {
  display: none !important;
}

body {
  margin: 0;
  padding: 2.5rem 1.25rem 4rem;
  background: #fff;
  color: var(--ink);
  font-family: var(--sans);
  line-height: 1.65;
  -webkit-text-size-adjust: 100%;
}

.page {
  max-width: 44rem;
  margin: 0 auto;
}

h1,
h2,
h3 {
  line-height: 1.25;
  letter-spacing: -0.01em;
  text-wrap: balance;
}

h1 {
  margin: 0 0 0.35rem;
  font-size: 1.7rem;
}

h2 {
  margin: 0 0 0.6rem;
  padding-top: 2.5rem;
  border-top: 1px solid var(--line);
  font-size: 1.25rem;
}

h3 {
  margin: 1.6rem 0 0.35rem;
  font-family: var(--mono);
  font-size: 0.95rem;
}

p {
  margin: 0 0 0.85rem;
}

a {
  color: var(--accent);
}

code,
pre {
  font-family: var(--mono);
  font-size: 0.875em;
}

code {
  padding: 0.1em 0.3em;
  border: 1px solid var(--line);
  border-radius: 4px;
  background: var(--surface);
}

pre {
  overflow-x: auto;
  margin: 0;
  padding: 0.85rem 1rem;
  border: 1px solid var(--line);
  border-radius: 6px;
  background: var(--surface);
  line-height: 1.5;
}

pre code {
  padding: 0;
  border: 0;
  background: none;
}

:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
}

.tagline {
  margin: 0 0 2rem;
  color: var(--muted);
  font-size: 1.05rem;
}

.hint {
  margin: 0.35rem 0 0;
  color: var(--muted);
  font-size: 0.8125rem;
}

.panel {
  padding: 1.25rem;
  border: 1px solid var(--line);
  border-radius: 8px;
}

.field + .field,
.field + fieldset {
  margin-top: 1rem;
}

.field > label,
legend {
  display: block;
  margin-bottom: 0.3rem;
  font-size: 0.8125rem;
  font-weight: 600;
  letter-spacing: 0.02em;
  text-transform: uppercase;
}

fieldset {
  min-width: 0;
  margin: 0;
  padding: 0.85rem 1rem 1rem;
  border: 1px solid var(--line);
  border-radius: 6px;
}

input[type="text"],
input[type="number"],
select,
textarea {
  width: 100%;
  padding: 0.5rem 0.6rem;
  border: 1px solid #c3c7cc;
  border-radius: 5px;
  background: #fff;
  color: inherit;
  font: inherit;
  font-family: var(--mono);
  font-size: 0.9375rem;
}

input[type="number"] {
  max-width: 7rem;
}

textarea {
  min-height: 3.25rem;
  resize: vertical;
}

input[type="checkbox"] {
  width: 1.05rem;
  height: 1.05rem;
  margin: 0;
  accent-color: var(--accent);
}

.options {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(9.5rem, 1fr));
  gap: 0.85rem 1rem;
}

.option > label {
  letter-spacing: 0;
  text-transform: none;
}

.option-inline {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  min-height: 2.4rem;
}

.result {
  margin-top: 1.25rem;
  padding: 1rem;
  border: 1px solid var(--line);
  border-left: 3px solid var(--accent);
  border-radius: 6px;
  background: var(--accent-wash);
}

.bar {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 0.5rem;
  margin-bottom: 0.5rem;
}

.bar > span {
  font-size: 0.8125rem;
  font-weight: 600;
  letter-spacing: 0.02em;
  text-transform: uppercase;
}

button {
  padding: 0.35rem 0.7rem;
  border: 1px solid var(--accent);
  border-radius: 5px;
  background: #fff;
  color: var(--accent);
  font: inherit;
  font-size: 0.8125rem;
  font-weight: 600;
  cursor: pointer;
}

button:hover {
  background: var(--accent);
  color: #fff;
}

.result-value {
  display: block;
  overflow-x: auto;
  font-family: var(--mono);
  font-size: 1.35rem;
  font-weight: 600;
  white-space: pre-wrap;
  word-break: break-word;
}

.note {
  margin: 0.85rem 0 0;
  color: var(--muted);
  font-size: 0.8125rem;
}

.message {
  margin: 0.75rem 0 0;
  font-size: 0.875rem;
}

.message.error {
  color: var(--accent);
}

.facts {
  margin: 0;
  padding: 0;
  list-style: none;
}

.facts li {
  padding: 0.3rem 0;
  border-bottom: 1px solid var(--line);
}

.facts li:last-child {
  border-bottom: 0;
}

.facts b {
  display: inline-block;
  min-width: 11rem;
}

footer {
  margin-top: 3rem;
  padding-top: 1.25rem;
  border-top: 1px solid var(--line);
  color: var(--muted);
  font-size: 0.875rem;
}

@media (max-width: 30rem) {
  .facts b {
    display: block;
    min-width: 0;
  }
}