/*
  Site implementation generated with OpenAI ChatGPT based on
  requirements, review, and approval by the project owner.
*/

:root {
  color-scheme: light dark;
  --page-bg: #f3f5f7;
  --card-bg: #ffffff;
  --text: #18202a;
  --muted: #66717f;
  --border: #d5dbe2;
  --soft-bg: #f7f9fb;
  --accent: #1959a6;
  --accent-hover: #12467f;
  --accent-text: #ffffff;
  --error: #a32929;
  --error-bg: #fff0f0;
  --warning: #775300;
  --warning-bg: #fff7dc;
  --focus-ring: rgba(25, 89, 166, 0.24);
  --shadow: 0 14px 40px rgba(22, 34, 48, 0.10);
}

* {
  box-sizing: border-box;
}

html {
  font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  background: var(--page-bg);
  color: var(--text);
}

body {
  margin: 0;
  min-height: 100vh;
}

button,
input {
  font: inherit;
}

button {
  cursor: pointer;
}

.page-shell {
  min-height: 100vh;
  display: grid;
  place-items: start center;
  padding: 48px 20px;
}

.converter-card {
  width: min(100%, 720px);
  background: var(--card-bg);
  border: 1px solid var(--border);
  border-radius: 18px;
  box-shadow: var(--shadow);
  padding: 34px;
}

.page-header {
  margin-bottom: 30px;
}

.eyebrow {
  margin: 0 0 6px;
  color: var(--accent);
  font-size: 0.78rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

h1 {
  margin: 0;
  font-size: clamp(1.7rem, 4vw, 2.35rem);
  line-height: 1.15;
  letter-spacing: -0.03em;
}

.lede {
  margin: 12px 0 0;
  color: var(--muted);
  line-height: 1.55;
}

.control-group {
  margin-top: 24px;
}

.control-label,
label {
  display: block;
  margin-bottom: 8px;
  font-size: 0.92rem;
  font-weight: 700;
}

.segmented {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 6px;
  padding: 5px;
  background: var(--soft-bg);
  border: 1px solid var(--border);
  border-radius: 12px;
}

.segment {
  min-height: 44px;
  border: 0;
  border-radius: 8px;
  background: transparent;
  color: var(--text);
  font-weight: 650;
}

.segment:hover {
  background: color-mix(in srgb, var(--accent) 8%, transparent);
}

.segment.is-active {
  background: var(--accent);
  color: var(--accent-text);
}

#converter-form {
  margin-top: 28px;
}

.field + .field {
  margin-top: 20px;
}

.label-row {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 8px;
}

.label-row label {
  margin: 0;
}

input {
  width: 100%;
  height: 48px;
  padding: 0 14px;
  border: 1px solid var(--border);
  border-radius: 10px;
  background: var(--card-bg);
  color: var(--text);
  outline: none;
}

input:focus {
  border-color: var(--accent);
  box-shadow: 0 0 0 4px var(--focus-ring);
}

input[aria-invalid="true"] {
  border-color: var(--error);
}

.field-note {
  margin: 7px 0 0;
  color: var(--muted);
  font-size: 0.84rem;
  line-height: 1.45;
}

.tooltip-wrap {
  position: relative;
  display: inline-flex;
}

.info-button {
  width: 22px;
  height: 22px;
  display: inline-grid;
  place-items: center;
  border: 1px solid var(--border);
  border-radius: 50%;
  background: var(--soft-bg);
  color: var(--muted);
  font-size: 0.78rem;
  font-weight: 800;
  line-height: 1;
}

.tooltip {
  position: absolute;
  z-index: 10;
  left: 50%;
  bottom: calc(100% + 10px);
  width: min(310px, 80vw);
  padding: 10px 12px;
  border: 1px solid var(--border);
  border-radius: 9px;
  background: var(--text);
  color: var(--card-bg);
  box-shadow: var(--shadow);
  font-size: 0.8rem;
  font-weight: 500;
  line-height: 1.45;
  opacity: 0;
  pointer-events: none;
  transform: translate(-50%, 4px);
  transition: opacity 120ms ease, transform 120ms ease;
}

.tooltip-wrap:hover .tooltip,
.tooltip-wrap:focus-within .tooltip {
  opacity: 1;
  transform: translate(-50%, 0);
}

.message {
  margin-top: 14px;
  padding: 10px 12px;
  border-radius: 9px;
  font-size: 0.88rem;
  line-height: 1.4;
}

.error-message {
  border: 1px solid color-mix(in srgb, var(--error) 35%, transparent);
  background: var(--error-bg);
  color: var(--error);
}

.warning-message {
  border: 1px solid color-mix(in srgb, var(--warning) 35%, transparent);
  background: var(--warning-bg);
  color: var(--warning);
}

.convert-button {
  width: 100%;
  min-height: 48px;
  margin-top: 22px;
  border: 0;
  border-radius: 10px;
  background: var(--accent);
  color: var(--accent-text);
  font-weight: 750;
}

.convert-button:hover {
  background: var(--accent-hover);
}

.convert-button:focus-visible,
.segment:focus-visible,
.copy-button:focus-visible,
.info-button:focus-visible {
  outline: 3px solid var(--focus-ring);
  outline-offset: 2px;
}

.result-card {
  margin-top: 24px;
  padding: 20px;
  border: 1px solid var(--border);
  border-radius: 12px;
  background: var(--soft-bg);
}

.result-heading-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
}

.result-heading {
  color: var(--muted);
  font-size: 0.85rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.result-value {
  margin-top: 7px;
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  font-size: clamp(1.65rem, 6vw, 2.55rem);
  font-weight: 750;
  letter-spacing: -0.035em;
  overflow-wrap: anywhere;
}

.copy-button {
  padding: 7px 11px;
  border: 1px solid var(--border);
  border-radius: 8px;
  background: var(--card-bg);
  color: var(--text);
  font-size: 0.84rem;
  font-weight: 650;
}

.result-details {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 12px;
  margin: 18px 0 0;
}

.result-details > div {
  padding-top: 14px;
  border-top: 1px solid var(--border);
}

.result-details dt {
  color: var(--muted);
  font-size: 0.8rem;
  font-weight: 700;
  text-transform: uppercase;
}

.result-details dd {
  margin: 4px 0 0;
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  font-size: 1.1rem;
  font-weight: 700;
}

.about-section {
  margin-top: 32px;
  padding-top: 26px;
  border-top: 1px solid var(--border);
}

.about-section h2 {
  margin: 0 0 12px;
  font-size: 1.08rem;
}

.about-section p {
  margin: 9px 0;
  color: var(--muted);
  font-size: 0.9rem;
  line-height: 1.55;
}

.documentation-note {
  padding-top: 5px;
  font-weight: 600;
}

[hidden] {
  display: none !important;
}

@media (max-width: 560px) {
  .page-shell {
    padding: 20px 12px;
  }

  .converter-card {
    padding: 22px 18px;
    border-radius: 14px;
  }

  .page-header {
    margin-bottom: 24px;
  }

  .segment {
    min-height: 46px;
  }

  input {
    height: 50px;
    font-size: 1rem;
  }

  .tooltip {
    left: auto;
    right: -10px;
    transform: translateY(4px);
  }

  .tooltip-wrap:hover .tooltip,
  .tooltip-wrap:focus-within .tooltip {
    transform: translateY(0);
  }
}

@media (prefers-color-scheme: dark) {
  :root {
    --page-bg: #101418;
    --card-bg: #171c21;
    --text: #edf1f5;
    --muted: #a6b0bb;
    --border: #333c46;
    --soft-bg: #1d232a;
    --accent: #70a8e8;
    --accent-hover: #8ab8ec;
    --accent-text: #0c1b2c;
    --error: #ff9a9a;
    --error-bg: #341d1d;
    --warning: #f0ce72;
    --warning-bg: #302918;
    --focus-ring: rgba(112, 168, 232, 0.28);
    --shadow: 0 14px 40px rgba(0, 0, 0, 0.28);
  }
}

#limits-copy {
  white-space: pre-line;
}