:root {
  --navy: #1f3a5f;
  --navy-deep: #15263f;
  --teal: #2a9d8f;
  --teal-dark: #1f7a70;
  --amber: #e9c46a;
  --ink: #1a2332;
  --muted: #5b6573;
  --line: #d7dee8;
  --bg: #f3f6fa;
  --card: #ffffff;
  --danger: #b42318;
  --radius: 14px;
  font-family: "Segoe UI", "Hiragino Sans", "Noto Sans CJK JP", "Noto Sans CJK SC",
    "PingFang SC", "Microsoft YaHei", system-ui, sans-serif;
}

* { box-sizing: border-box; }
html, body { margin: 0; padding: 0; }
body {
  background: radial-gradient(1200px 500px at 10% -10%, #e4eef5 0%, var(--bg) 55%);
  color: var(--ink);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}
a { color: var(--teal-dark); }
a:hover { color: var(--navy); }

.top {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1rem 1.5rem;
  border-bottom: 1px solid var(--line);
  background: rgba(255, 255, 255, 0.9);
  backdrop-filter: blur(8px);
  position: sticky;
  top: 0;
  z-index: 2;
}
.brand { display: flex; align-items: center; gap: 0.6rem; font-weight: 700; color: var(--navy); }
.lang { display: flex; gap: 0.25rem; }
.lang button {
  border: 1px solid var(--line);
  background: #fff;
  color: var(--muted);
  border-radius: 999px;
  padding: 0.25rem 0.7rem;
  cursor: pointer;
  font: inherit;
  font-size: 0.85rem;
}
.lang button.is-active { background: var(--navy); color: #fff; border-color: var(--navy); }

main { width: min(1080px, calc(100% - 2rem)); margin: 1.5rem auto 2rem; flex: 1; }
.hero h1 {
  font-size: clamp(1.6rem, 3vw, 2.2rem);
  line-height: 1.25;
  color: var(--navy);
  margin: 0 0 0.75rem;
}
.lede { color: var(--muted); line-height: 1.6; margin: 0 0 1rem; max-width: 46rem; }
.pill {
  display: inline-block;
  background: #e6f6f3;
  color: var(--teal-dark);
  font-weight: 600;
  font-size: 0.9rem;
  padding: 0.35rem 0.75rem;
  border-radius: 999px;
  margin: 0;
}

.drop {
  margin-top: 1.5rem;
  border: 2px dashed #b8c4d4;
  border-radius: var(--radius);
  background: #fff;
  padding: 2.4rem 1.5rem;
  text-align: center;
  transition: border-color 0.15s, background 0.15s;
}
.drop.is-over { border-color: var(--teal); background: #f2fbf9; }
.drop-title { font-weight: 700; color: var(--navy); margin: 0 0 0.35rem; }
.drop-hint { color: var(--muted); margin: 0 0 1rem; }

.btn {
  font: inherit;
  border: 1px solid var(--line);
  background: #fff;
  color: var(--navy);
  border-radius: 10px;
  padding: 0.5rem 0.95rem;
  cursor: pointer;
}
.btn:hover { border-color: var(--navy); }
.btn-primary { background: var(--teal); border-color: var(--teal); color: #fff; font-weight: 650; }
.btn-primary:hover { background: var(--teal-dark); border-color: var(--teal-dark); }
.btn:disabled { opacity: 0.5; cursor: not-allowed; }

.workspace { margin-top: 1.25rem; }
.is-hidden { display: none !important; }

.toolbar {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 0.9rem 1rem;
  display: grid;
  gap: 0.6rem;
}
.check { display: flex; gap: 0.55rem; align-items: flex-start; color: var(--ink); font-size: 0.95rem; }
.check input { margin-top: 0.2rem; }
.toolbar-actions { display: flex; gap: 0.5rem; justify-content: flex-end; flex-wrap: wrap; }
.status { margin: 0.8rem 0 0; color: var(--navy); font-weight: 600; }
.status.is-warn { color: var(--danger); }

.files { display: grid; gap: 1rem; margin-top: 1rem; }
.card {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 1rem 1rem 0.7rem;
  overflow: auto;
}
.card-head {
  display: flex;
  justify-content: space-between;
  gap: 1rem;
  flex-wrap: wrap;
  align-items: baseline;
}
.card h2 { margin: 0; font-size: 1.05rem; color: var(--navy); word-break: break-all; }
.meta { color: var(--muted); font-size: 0.85rem; }
.controls { display: flex; gap: 0.75rem; flex-wrap: wrap; align-items: center; margin: 0.75rem 0; }
.controls label { font-size: 0.9rem; color: var(--muted); }
.controls select {
  font: inherit;
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 0.3rem 0.5rem;
  background: #fff;
}
.preview { width: 100%; border-collapse: collapse; font-size: 0.82rem; margin: 0.2rem 0 0.8rem; }
.preview th, .preview td {
  border: 1px solid var(--line);
  padding: 0.28rem 0.45rem;
  text-align: left;
  white-space: nowrap;
  max-width: 16rem;
  overflow: hidden;
  text-overflow: ellipsis;
}
.preview th { background: var(--navy); color: #fff; font-weight: 600; }
.preview tr:nth-child(even) td { background: #f7f9fc; }

footer {
  border-top: 1px solid var(--line);
  padding: 1.25rem 1.5rem 2rem;
  background: var(--navy-deep);
  color: #d5deea;
}
.foot-note { width: min(1080px, 100%); margin: 0 auto; line-height: 1.6; font-size: 0.92rem; }
footer a { color: var(--amber); }
footer a:hover { color: #fff; }

/* tabs + JSON / table -> CSV */
.tabs { display: flex; gap: 0.35rem; margin-top: 1.4rem; border-bottom: 1px solid var(--line); flex-wrap: wrap; }
.tab {
  font: inherit;
  font-weight: 600;
  border: 1px solid transparent;
  border-bottom: none;
  background: transparent;
  color: var(--muted);
  padding: 0.55rem 1rem;
  border-radius: 10px 10px 0 0;
  cursor: pointer;
  margin-bottom: -1px;
}
.tab:hover { color: var(--navy); }
.tab.is-active { background: #fff; color: var(--navy); border-color: var(--line); border-bottom: 1px solid #fff; }
.tab:focus-visible, .btn:focus-visible, .paste:focus-visible { outline: 3px solid var(--amber); outline-offset: 2px; }
#panel-fix .drop { margin-top: 1rem; }
.convert { margin-top: 1rem; display: grid; gap: 0.7rem; }
.convert-head { display: flex; flex-wrap: wrap; gap: 0.6rem 1rem; align-items: flex-end; justify-content: space-between; }
.field-label { font-weight: 700; color: var(--navy); }
.convert-opts { display: flex; flex-wrap: wrap; gap: 0.5rem 1rem; }
.inline { display: flex; align-items: center; gap: 0.4rem; font-size: 0.9rem; color: var(--muted); }
.inline select {
  font: inherit;
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 0.3rem 0.5rem;
  background: #fff;
  color: var(--ink);
}
.inline select:disabled { opacity: 0.5; }
.paste {
  width: 100%;
  min-height: 12rem;
  resize: vertical;
  font: 0.85rem/1.5 ui-monospace, SFMono-Regular, Menlo, Consolas, "Noto Sans Mono CJK JP", monospace;
  border: 2px dashed #b8c4d4;
  border-radius: var(--radius);
  background: #fff;
  padding: 0.9rem 1rem;
  color: var(--ink);
}
.paste:focus { border-color: var(--teal); background: #fbfefd; }
.drop-hint.small { font-size: 0.85rem; margin: -0.3rem 0 0; }
.scroll-x { overflow-x: auto; }
.csv-out {
  margin: 0;
  background: #f7f9fc;
  border: 1px solid var(--line);
  border-radius: 10px;
  padding: 0.7rem 0.9rem;
  font: 0.8rem/1.5 ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  white-space: pre;
  overflow-x: auto;
  max-height: 16rem;
}

@media (max-width: 640px) {
  .toolbar-actions { justify-content: stretch; }
  .toolbar-actions .btn { flex: 1; }
}