:root {
  --bg: #fbfbfa;
  --panel: #ffffff;
  --panel-2: #f4f4f2;
  --line: #e4e3df;
  --line-strong: #d3d2cc;
  --ink: #1c1c1a;
  --ink-dim: #6b6b64;
  --ink-faint: #9d9c95;
  --accent: #B45309;
  --accent-soft: #fef3c7;
  --teal: #0ea88e;
  --teal-soft: #e3f7f2;
  --amber: #d97706;
  --red: #dc2626;
  --radius: 12px;
  --disp: 'Space Grotesk', sans-serif;
  --body: 'IBM Plex Sans', sans-serif;
  --mono: 'IBM Plex Mono', monospace;
}

*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
body { background: var(--bg); color: var(--ink); font-family: var(--body); }
::selection { background: var(--accent-soft); color: var(--accent); }

.wrap { max-width: 980px; margin: 0 auto; }
.top-actions { display: flex; justify-content: flex-end; margin-bottom: 14px; }

.card {
  background: var(--panel); border: 1px solid var(--line);
  border-radius: var(--radius); padding: 24px 26px;
  margin-bottom: 20px; box-shadow: 0 1px 4px rgba(0,0,0,.04);
}
.card h2 { font-family: var(--disp); font-size: 15px; font-weight: 600; color: var(--ink); margin-bottom: 16px; }

.meta-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 14px; }
@media (max-width: 600px) { .meta-grid { grid-template-columns: repeat(2, 1fr); } }
.meta-item .label { font-family: var(--mono); font-size: 10px; letter-spacing: 1px; text-transform: uppercase; color: var(--ink-faint); margin-bottom: 4px; }
.meta-item .value { font-family: var(--mono); font-size: 13px; font-weight: 600; color: var(--ink); white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }

.settings-row { display: grid; grid-template-columns: 1fr 1fr; gap: 32px; align-items: start; }
@media (max-width: 720px) { .settings-row { grid-template-columns: 1fr; } }

.wave-scroll { overflow-x: auto; border: 1px solid var(--line); border-radius: 8px; background: var(--panel-2); margin-bottom: 14px; }
.wave-canvas { display: block; width: 100%; min-width: 280px; }

/* click legend in result */
.click-legend {
  font-family: var(--mono); font-size: 10px; color: var(--ink-faint);
  display: flex; align-items: center; gap: 6px; margin-bottom: 6px;
}
.click-dot-legend {
  display: inline-block; width: 10px; height: 2px;
  background: #ef4444; border-radius: 1px;
}

/* preview row */
.preview-row { display: flex; gap: 8px; }
.half-btn { flex: 1; }

/* mode tabs */
.mode-tabs { display: flex; gap: 0; border: 1px solid var(--line-strong); border-radius: 8px; overflow: hidden; margin-bottom: 8px; }
.mode-tab { flex: 1; font-family: var(--mono); font-size: 12px; font-weight: 600; padding: 9px 12px; border: none; background: var(--panel-2); color: var(--ink-dim); cursor: pointer; transition: all .1s; }
.mode-tab:not(:last-child) { border-right: 1px solid var(--line-strong); }
.mode-tab.active { background: var(--accent); color: #fff; }
.mode-hint { font-family: var(--mono); font-size: 10px; color: var(--ink-faint); line-height: 1.5; margin-top: 2px; }

/* controls */
.ctrl { margin-bottom: 16px; }
.ctrl label { font-family: var(--mono); font-size: 10.5px; letter-spacing: 1px; text-transform: uppercase; color: var(--ink-faint); display: flex; justify-content: space-between; align-items: baseline; margin-bottom: 8px; }
.ctrl .val { font-size: 13px; font-weight: 700; color: var(--accent); letter-spacing: 0; text-transform: none; }
.freq-hint { font-family: var(--mono); font-size: 9.5px; color: var(--ink-faint); margin-top: 4px; }
.ctrl input[type=range] { -webkit-appearance: none; appearance: none; width: 100%; height: 4px; background: var(--line-strong); border-radius: 2px; outline: none; cursor: pointer; }
.ctrl input[type=range]::-webkit-slider-thumb { -webkit-appearance: none; width: 16px; height: 16px; border-radius: 50%; background: #fff; border: 2px solid var(--accent); box-shadow: 0 1px 4px rgba(180,83,9,.25); cursor: pointer; transition: transform .1s; }
.ctrl input[type=range]::-webkit-slider-thumb:hover { transform: scale(1.15); }
.ctrl input[type=range]::-moz-range-thumb { width: 16px; height: 16px; border-radius: 50%; background: #fff; border: 2px solid var(--accent); cursor: pointer; }

/* preset buttons */
.preset-btns { display: flex; flex-wrap: wrap; gap: 6px; }
.preset-btn { font-family: var(--mono); font-size: 10.5px; font-weight: 600; padding: 5px 10px; border-radius: 6px; border: 1px solid var(--line-strong); background: var(--panel-2); color: var(--ink-dim); cursor: pointer; transition: all .1s; }
.preset-btn:hover { border-color: var(--accent); color: var(--accent); }
.preset-btn.active { background: var(--accent); border-color: var(--accent); color: #fff; }

.out-select { font-family: var(--mono); font-size: 12.5px; width: 100%; padding: 10px 12px; border: 1px solid var(--line-strong); border-radius: 8px; background: var(--panel-2); color: var(--ink); cursor: pointer; outline: none; transition: border-color .1s; }
.out-select:focus { border-color: var(--accent); }
.out-format { margin-bottom: 18px; }

.btn { display: inline-flex; align-items: center; justify-content: center; gap: 8px; font-family: var(--mono); font-size: 13px; font-weight: 700; padding: 12px 20px; border-radius: 8px; border: none; background: var(--accent); color: #fff; cursor: pointer; width: 100%; margin-bottom: 12px; transition: filter .12s, opacity .12s; }
.btn:hover:not(:disabled) { filter: brightness(1.08); }
.btn:disabled { opacity: .38; cursor: not-allowed; }
.btn.ghost { background: transparent; border: 1px solid var(--line-strong); color: var(--ink-dim); margin-bottom: 0; }
.btn.ghost:hover:not(:disabled) { filter: none; border-color: var(--accent); color: var(--accent); }
.btn.download-result { background: var(--teal); width: auto; padding: 10px 18px; margin-bottom: 0; }

.bar { height: 4px; background: var(--line); border-radius: 2px; overflow: hidden; margin-bottom: 8px; }
.bar i { display: block; height: 100%; width: 0%; background: linear-gradient(90deg, var(--teal), var(--accent)); border-radius: 2px; transition: width .15s ease; }
.status-line { font-family: var(--mono); font-size: 11px; color: var(--ink-faint); min-height: 16px; }

.result-header { display: flex; align-items: center; justify-content: space-between; margin-bottom: 20px; flex-wrap: wrap; gap: 10px; }
.result-heading h2 { margin-bottom: 4px; }
.status-pill { display: inline-flex; align-items: center; gap: 6px; font-family: var(--mono); font-size: 10.5px; font-weight: 700; letter-spacing: .5px; text-transform: uppercase; color: var(--teal); }
.pip { width: 7px; height: 7px; border-radius: 50%; background: var(--teal); display: inline-block; }
.result-body { display: grid; grid-template-columns: 1fr 1fr; gap: 28px; }
@media (max-width: 700px) { .result-body { grid-template-columns: 1fr; } }
.result-side { display: flex; flex-direction: column; gap: 16px; }
.file-pair { display: grid; grid-template-columns: 1fr 1fr; gap: 14px; padding: 14px; background: var(--panel-2); border-radius: 8px; border: 1px solid var(--line); }
.file-pair .label { font-family: var(--mono); font-size: 10px; letter-spacing: 1px; text-transform: uppercase; color: var(--ink-faint); margin-bottom: 4px; }
.file-pair .fname { font-family: var(--mono); font-size: 12px; color: var(--ink); word-break: break-all; }
.result-stats { display: flex; flex-direction: column; }
.stat-row { display: flex; justify-content: space-between; align-items: center; font-family: var(--mono); font-size: 11.5px; padding: 7px 0; border-bottom: 1px solid var(--line); }
.stat-label { color: var(--ink-faint); }
.stat-value { color: var(--ink); font-weight: 600; }
.stat-value.accent { color: var(--accent); }
.result-info-box { font-family: var(--body); font-size: 12.5px; line-height: 1.6; color: var(--ink-dim); background: var(--accent-soft); border-radius: 8px; padding: 10px 14px; }