:root {
  --bg: #0e1116;
  --panel: #171b22;
  --panel2: #1d222b;
  --line: #2a313c;
  --fg: #e8ecf2;
  --dim: #98a2b3;
  --accent: #4c8dff;
  --accent2: #2f6fe0;
  --ok: #39d98a;
  --warn: #ffbe4d;
  --teach: #c2410c;
}

* { box-sizing: border-box; }
html, body { height: 100%; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--fg);
  font: 15px/1.55 "Microsoft YaHei UI", "Microsoft YaHei", "PingFang SC", "Segoe UI", system-ui, sans-serif;
  display: flex;
  flex-direction: column;
  overflow: hidden;
  -webkit-text-size-adjust: 100%;
}

/* ---------- 顶栏 ---------- */
header#topbar {
  display: flex; align-items: center; gap: 10px;
  padding: 10px 14px;
  border-bottom: 1px solid var(--line);
  background: var(--panel);
  flex: 0 0 auto;
}
header h1 { font-size: 15px; margin: 0; font-weight: 600; letter-spacing: .5px; white-space: nowrap; }
.badge {
  font-size: 12px; color: var(--dim);
  border: 1px solid var(--line); border-radius: 999px;
  padding: 2px 8px; white-space: nowrap;
}
.badge.ok { color: var(--ok); border-color: #245c40; }
.sp { flex: 1; }

/* ---------- 布局 ---------- */
main { flex: 1; display: flex; min-height: 0; }
.left { flex: 1; display: flex; flex-direction: column; min-width: 0; padding: 12px; gap: 10px; }
.right {
  width: 340px; flex: 0 0 auto;
  border-left: 1px solid var(--line);
  background: var(--panel);
  padding: 12px; overflow-y: auto;
  display: flex; flex-direction: column; gap: 12px;
}

/* ---------- 手写区 ---------- */
.padwrap {
  position: relative; flex: 1; min-height: 0;
  border-radius: 12px; overflow: hidden;
  border: 1px solid var(--line); background: #fbfcfe;
}
canvas#pad { display: block; width: 100%; height: 100%; touch-action: none; cursor: crosshair; }

.toolbar { display: flex; gap: 8px; align-items: center; flex-wrap: wrap; flex: 0 0 auto; }
.segbar { font-size: 12px; color: var(--dim); display: flex; align-items: center; gap: 6px; }
.segbar input[type=range] { width: 110px; }

/* 教学模式提示条 */
.teachbox {
  display: none;
  align-items: center; gap: 8px; flex-wrap: wrap;
  padding: 8px 12px; border-radius: 10px;
  background: #2a1a10; border: 1px solid var(--teach); color: #ffd9c2;
  font-size: 13px;
}
.teachbox b { color: #ffb28a; font-size: 18px; }
.teachbox .dim { color: #d8a98c; }

/* ---------- 按钮 / 表单 ---------- */
button {
  font: inherit; color: var(--fg); background: var(--panel2);
  border: 1px solid var(--line); border-radius: 9px;
  padding: 7px 13px; cursor: pointer; transition: .12s;
  white-space: nowrap;
}
button:hover { background: #242b36; border-color: #3a4453; }
button:active { transform: translateY(1px); }
button:disabled { opacity: .45; cursor: not-allowed; }
button.primary { background: var(--accent2); border-color: var(--accent2); }
button.primary:hover { background: var(--accent); }
.wfull { width: 100%; }
.mt8 { margin-top: 8px; }

input[type=text], input[type=number], select {
  font: inherit; width: 100%;
  background: var(--panel2); color: var(--fg);
  border: 1px solid var(--line); border-radius: 8px;
  padding: 6px 8px; outline: none;
}
input[type=text]:focus, select:focus { border-color: var(--accent); }
input[type=range] { width: 100%; }
label { user-select: none; }

/* ---------- 结果区 ---------- */
.out { display: flex; gap: 8px; align-items: stretch; flex: 0 0 auto; }
.out .col { display: flex; flex-direction: column; gap: 6px; }
textarea#result {
  flex: 1; height: 64px; resize: none;
  font: 20px/1.4 "Microsoft YaHei UI", "Microsoft YaHei", sans-serif;
  background: var(--panel2); color: var(--fg);
  border: 1px solid var(--line); border-radius: 10px;
  padding: 8px 10px; outline: none;
}
textarea#result:focus { border-color: var(--accent); }

/* ---------- 候选 ---------- */
.label { font-size: 12px; color: var(--dim); letter-spacing: .5px; }
.rank { font-size: 10px; color: var(--dim); vertical-align: top; margin-left: 2px; }
#cands { display: flex; flex-wrap: wrap; gap: 6px; min-height: 78px; align-content: flex-start; margin-top: 6px; }
.chip {
  min-width: 42px; height: 46px; padding: 0 8px;
  font-size: 24px; line-height: 46px; text-align: center;
  background: var(--panel2); border: 1px solid var(--line);
  border-radius: 10px; cursor: pointer; user-select: none; transition: .12s;
}
.chip:hover { border-color: var(--accent); background: #22293a; }
.chip.top { border-color: var(--accent); background: #1c2740; }
.empty { color: var(--dim); font-size: 13px; padding: 8px 2px; }

/* ---------- 分组 ---------- */
fieldset { border: 1px solid var(--line); border-radius: 10px; padding: 10px 12px; margin: 0; }
legend { font-size: 12px; color: var(--dim); padding: 0 6px; }
.kv { display: flex; justify-content: space-between; font-size: 12px; color: var(--dim); gap: 8px; }
.hint { font-size: 12px; color: var(--dim); line-height: 1.6; }

/* ---------- 状态栏 / 页脚 ---------- */
.status { font-size: 12px; color: var(--dim); min-height: 18px; display: flex; gap: 8px; align-items: center; flex: 0 0 auto; }
.dot { width: 7px; height: 7px; border-radius: 50%; background: var(--ok); flex: 0 0 auto; }
.dot.busy { background: var(--warn); }
footer { border-top: 1px solid var(--line); padding: 6px 14px; font-size: 12px; color: var(--dim); flex: 0 0 auto; }
kbd {
  background: var(--panel2); border: 1px solid var(--line); border-bottom-width: 2px;
  border-radius: 5px; padding: 1px 5px; font: 11px/1.4 Consolas, monospace;
}
#history { display: flex; flex-wrap: wrap; gap: 5px; margin-top: 6px; }
#history .h {
  font-size: 17px; padding: 2px 9px;
  background: var(--panel2); border: 1px solid var(--line);
  border-radius: 8px; cursor: pointer;
}
#history .h:hover { border-color: var(--accent); }

/* ---------- 嵌入模式（?embed=1） ---------- */
body.embed header#topbar,
body.embed footer { display: none; }
body.embed .right { width: 300px; }

/* ---------- 窄屏：候选挪到下面 ---------- */
@media (max-width: 760px) {
  main { flex-direction: column; }
  .right { width: auto; border-left: none; border-top: 1px solid var(--line); max-height: 46vh; }
  .padwrap { min-height: 220px; }
  .left { padding: 8px; gap: 8px; }
  .out { flex-wrap: wrap; }
  textarea#result { width: 100%; }
  footer { display: none; }
}