@import url("https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600;700&display=swap");

:root {
  --paper: #f5f5f3;
  --canvaswhite: #ffffff;
  --ink: #0a0a0a;
  --hairline: #e3e3e0;
  --edge: #111111;
  --muted: #6b6b68;
  --danger: #8a1f1f;
  --ok: #14532d;
  --weak: #8a1f1f;
  --fair: #a35b00;
  --good: #226b3d;
  --strong: #14532d;
}

* {
  box-sizing: border-box;
}

html,
body {
  height: 100%;
}

body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font-family: "Inter", system-ui, -apple-system, sans-serif;
  font-weight: 400;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

.wrap {
  max-width: 720px;
  margin: 0 auto;
  padding: 96px 24px 48px;
}

.hero {
  text-align: center;
  margin-bottom: 40px;
}

.hero h1 {
  font-size: clamp(1.75rem, 4vw, 2.75rem);
  font-weight: 700;
  letter-spacing: -0.02em;
  line-height: 1.15;
  margin: 0 0 16px;
}

.hero .sub {
  color: var(--muted);
  font-size: 1rem;
  margin: 0;
}

.card {
  background: var(--canvaswhite);
  border: 1px solid var(--hairline);
  border-radius: 2px;
  padding: 20px;
}

.pwd-row {
  display: flex;
  align-items: center;
  gap: 12px;
}

.pwd {
  flex: 1;
  min-width: 0;
  font-family: "SF Mono", "Menlo", "Consolas", monospace;
  font-size: 1.25rem;
  letter-spacing: 0.02em;
  overflow-x: auto;
  white-space: nowrap;
  padding: 4px 0;
}

.icon-btn {
  flex-shrink: 0;
  background: transparent;
  border: 1px solid var(--hairline);
  border-radius: 2px;
  width: 40px;
  height: 40px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--ink);
  cursor: pointer;
  transition: border-color 0.15s;
}

.icon-btn:hover {
  border-color: var(--edge);
}

.icon-btn.spin svg {
  animation: spin 0.5s linear;
}

@keyframes spin {
  to {
    transform: rotate(360deg);
  }
}

.btn-primary {
  flex-shrink: 0;
  background: var(--edge);
  color: var(--canvaswhite);
  border: 1px solid var(--edge);
  border-radius: 2px;
  padding: 0 20px;
  height: 40px;
  font-family: inherit;
  font-size: 0.9rem;
  font-weight: 500;
  cursor: pointer;
  transition: opacity 0.15s;
  white-space: nowrap;
}

.btn-primary:hover {
  opacity: 0.85;
}

.btn-primary.copied {
  background: var(--ok);
  border-color: var(--ok);
}

.meter-row {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-top: 16px;
}

.meter {
  flex: 1;
  height: 4px;
  background: var(--hairline);
  border-radius: 2px;
  overflow: hidden;
}

.meter-fill {
  height: 100%;
  width: 0%;
  background: var(--weak);
  transition:
    width 0.2s,
    background 0.2s;
}

.meter-fill[data-level="weak"] {
  background: var(--weak);
}
.meter-fill[data-level="fair"] {
  background: var(--fair);
}
.meter-fill[data-level="good"] {
  background: var(--good);
}
.meter-fill[data-level="strong"] {
  background: var(--strong);
}

.strength-label {
  font-size: 0.8rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--muted);
  flex-shrink: 0;
}

.options {
  margin-top: 32px;
  padding: 24px;
  border-radius: 2px;
}

.hairline {
  border: 1px solid var(--hairline);
}

.option-row + .option-row {
  margin-top: 24px;
}

.label {
  display: block;
  font-size: 0.7rem;
  text-transform: uppercase;
  letter-spacing: 0.18em;
  color: var(--muted);
  margin-bottom: 12px;
}

#length-value {
  color: var(--ink);
  font-weight: 600;
}

input[type="range"] {
  -webkit-appearance: none;
  width: 100%;
  height: 2px;
  background: var(--hairline);
  outline: none;
}

input[type="range"]::-webkit-slider-thumb {
  -webkit-appearance: none;
  width: 18px;
  height: 18px;
  border-radius: 50%;
  background: var(--canvaswhite);
  border: 2px solid var(--edge);
  cursor: pointer;
}

input[type="range"]::-moz-range-thumb {
  width: 18px;
  height: 18px;
  border-radius: 50%;
  background: var(--canvaswhite);
  border: 2px solid var(--edge);
  cursor: pointer;
}

.check-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 12px 20px;
}

.check {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 0.9rem;
  cursor: pointer;
  user-select: none;
}

.check input[type="checkbox"] {
  width: 18px;
  height: 18px;
  accent-color: var(--edge);
  cursor: pointer;
}

.error {
  color: var(--danger);
  font-size: 0.85rem;
  text-align: center;
  min-height: 1.2em;
  margin: 16px 0 0;
}

.footer {
  text-align: center;
  margin-top: 48px;
}

@media (max-width: 520px) {
  .wrap {
    padding: 56px 16px 32px;
  }

  .pwd-row {
    flex-wrap: wrap;
  }

  .pwd {
    flex-basis: 100%;
    order: -1;
    font-size: 1.05rem;
  }

  .btn-primary {
    flex: 1;
  }

  .check-grid {
    grid-template-columns: 1fr;
  }
}