:root {
  --mint: #10b981;
  --mint-strong: #059669;
  --mint-soft: #d1fae5;
  --mint-faint: #ecfdf5;
  --mint-line: #6ee7b7;
  --ink: #064e3b;
  --muted: #4b7a6a;
  --card: #ffffff;
  --bg: linear-gradient(160deg, #d1fae5 0%, #ecfeff 60%, #f0fdf4 100%);
  --shadow: 0 20px 50px -12px rgba(16, 185, 129, .28);
  --digit: #0e7490;
  --symbol: #db2777;
  --weak: #ef4444;
  --fair: #f59e0b;
  color-scheme: light;
}

@media (prefers-color-scheme: dark) {
  :root {
    --mint: #34d399;
    --mint-strong: #6ee7b7;
    --mint-soft: #134e3a;
    --mint-faint: #0b2b22;
    --mint-line: #1f6b52;
    --ink: #e6fff5;
    --muted: #8fbfae;
    --card: #0f1f1a;
    --bg: radial-gradient(circle at 20% 0%, #064e3b 0%, #04140f 70%);
    --shadow: 0 20px 50px -12px rgba(0, 0, 0, .6);
    --digit: #67e8f9;
    --symbol: #f9a8d4;
    color-scheme: dark;
  }
}

* { box-sizing: border-box; }

html, body { margin: 0; min-height: 100%; }

body {
  min-height: 100vh;
  min-height: 100dvh;
  display: grid;
  place-items: center;
  padding: max(16px, env(safe-area-inset-top)) 16px max(16px, env(safe-area-inset-bottom));
  background: var(--bg);
  background-attachment: fixed;
  color: var(--ink);
  font: 16px/1.5 system-ui, -apple-system, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  -webkit-font-smoothing: antialiased;
}

.card {
  width: 100%;
  max-width: 440px;
  background: var(--card);
  border-radius: 28px;
  padding: 24px;
  box-shadow: var(--shadow);
}

.top { display: flex; align-items: center; justify-content: space-between; margin-bottom: 16px; }
.brand { margin: 0; font-size: 22px; font-weight: 800; letter-spacing: -.01em; }
.leaf { display: inline-block; }

button { font: inherit; color: inherit; cursor: pointer; -webkit-tap-highlight-color: transparent; }
button:focus-visible, input:focus-visible { outline: 3px solid var(--mint); outline-offset: 2px; }

.lang {
  min-width: 44px; min-height: 36px;
  border: 1.5px solid var(--mint-line);
  background: transparent;
  border-radius: 999px;
  padding: 0 12px;
  font-size: 13px; font-weight: 700;
  color: var(--mint-strong);
}

.password {
  display: block;
  min-height: 64px;
  padding: 16px 18px;
  background: var(--mint-faint);
  border: 2px dashed var(--mint-line);
  border-radius: 18px;
  font: 600 20px/1.45 ui-monospace, "SF Mono", Menlo, Consolas, monospace;
  letter-spacing: .04em;
  word-break: break-all;
  user-select: all;
  -webkit-user-select: all;
}
.password .d { color: var(--digit); }
.password .s { color: var(--symbol); }

.meter { height: 6px; margin-top: 12px; border-radius: 3px; background: var(--mint-soft); overflow: hidden; }
.meter-bar { height: 100%; width: 0; border-radius: 3px; background: var(--mint); transition: width .3s ease, background-color .3s ease; }
.meter-bar[data-level="0"] { background: var(--weak); }
.meter-bar[data-level="1"] { background: var(--fair); }
.strength { margin: 6px 0 0; font-size: 13px; font-weight: 600; color: var(--muted); }

.actions { display: flex; gap: 10px; margin-top: 16px; }
.btn { min-height: 52px; border: 0; border-radius: 999px; font-weight: 700; transition: transform .12s ease, background-color .2s ease; }
.btn:active { transform: scale(.97); }
.btn-primary { flex: 1; background: var(--mint); color: #fff; font-size: 17px; box-shadow: 0 8px 20px -8px var(--mint); }
.btn-primary:hover { background: var(--mint-strong); }
.btn-primary.copied { background: var(--mint-strong); }
.btn-icon { width: 52px; display: grid; place-items: center; background: var(--mint-soft); color: var(--mint-strong); }
.btn-icon:active svg { transform: rotate(-180deg); }
.btn-icon svg { transition: transform .35s ease; }

@media (prefers-color-scheme: dark) {
  .btn-primary { color: #04140f; }
}

.toast { min-height: 20px; margin: 8px 0 0; text-align: center; font-size: 13px; color: var(--mint-strong); }

.settings { margin-top: 12px; padding-top: 18px; border-top: 1px solid var(--mint-soft); display: grid; gap: 16px; }
.row { display: flex; align-items: center; justify-content: space-between; font-weight: 600; }
.length-value { min-width: 2.5em; text-align: center; padding: 2px 10px; border-radius: 999px; background: var(--mint-soft); color: var(--mint-strong); font-variant-numeric: tabular-nums; }

input[type="range"] {
  --fill: 17%;
  width: 100%; height: 28px; margin: -8px 0 0; background: transparent;
  -webkit-appearance: none; appearance: none; cursor: pointer;
}
input[type="range"]::-webkit-slider-runnable-track {
  height: 8px; border-radius: 4px;
  background: linear-gradient(to right, var(--mint) var(--fill), var(--mint-soft) var(--fill));
}
input[type="range"]::-moz-range-track { height: 8px; border-radius: 4px; background: var(--mint-soft); }
input[type="range"]::-moz-range-progress { height: 8px; border-radius: 4px; background: var(--mint); }
input[type="range"]::-webkit-slider-thumb {
  -webkit-appearance: none; width: 26px; height: 26px; margin-top: -9px; border-radius: 50%;
  background: #fff; border: 3px solid var(--mint); box-shadow: 0 2px 6px rgba(16, 185, 129, .35);
}
input[type="range"]::-moz-range-thumb {
  width: 20px; height: 20px; border-radius: 50%;
  background: #fff; border: 3px solid var(--mint); box-shadow: 0 2px 6px rgba(16, 185, 129, .35);
}

.chips { border: 0; margin: 0; padding: 0; display: flex; flex-wrap: wrap; gap: 8px; }
.chips legend { padding: 0; margin-bottom: 8px; font-weight: 600; }
.chip { position: relative; }
.chip input { position: absolute; opacity: 0; inset: 0; margin: 0; cursor: pointer; }
.chip span {
  display: inline-flex; align-items: center; min-height: 44px; padding: 0 18px;
  border-radius: 999px; border: 1.5px solid var(--mint-line);
  font: 600 14px ui-monospace, Menlo, monospace;
  color: var(--muted);
  transition: background-color .15s ease, color .15s ease;
}
.chip input:checked + span { background: var(--mint); border-color: var(--mint); color: #fff; }
.chip input:focus-visible + span { outline: 3px solid var(--mint); outline-offset: 2px; }
.chip input:disabled { cursor: not-allowed; }
.chip input:disabled + span { opacity: .6; }
@media (prefers-color-scheme: dark) { .chip input:checked + span { color: #04140f; } }

.switch { display: flex; align-items: center; gap: 12px; min-height: 44px; cursor: pointer; font-weight: 600; }
.switch input { position: absolute; opacity: 0; width: 1px; height: 1px; }
.track { flex: none; width: 46px; height: 28px; border-radius: 999px; background: var(--mint-soft); position: relative; transition: background-color .2s ease; }
.track::after { content: ""; position: absolute; top: 3px; left: 3px; width: 22px; height: 22px; border-radius: 50%; background: #fff; box-shadow: 0 1px 3px rgba(0,0,0,.2); transition: transform .2s ease; }
.switch input:checked + .track { background: var(--mint); }
.switch input:checked + .track::after { transform: translateX(18px); }
.switch input:focus-visible + .track { outline: 3px solid var(--mint); outline-offset: 2px; }
.muted { color: var(--muted); font-weight: 400; font-family: ui-monospace, Menlo, monospace; }

.symbols { display: grid; gap: 8px; }
.symbols input {
  width: 100%; min-height: 44px; padding: 8px 14px;
  border: 1.5px solid var(--mint-line); border-radius: 14px;
  background: var(--mint-faint); color: var(--ink);
  font: 16px ui-monospace, Menlo, monospace;
}
.link { border: 0; background: none; padding: 6px 0; font-size: 13px; font-weight: 600; color: var(--mint-strong); }
.hint { margin: 0; font-size: 13px; color: var(--fair); }

.foot { margin-top: 20px; text-align: center; font-size: 12px; color: var(--muted); }

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { transition: none !important; animation: none !important; }
}