:root {
  --bg: #f7f7f5;
  --panel: #ffffff;
  --panel-2: #f1f1ee;
  --ink: #16181d;
  --ink-dim: #5d6470;
  --line: #e2e2dd;
  --accent: #b4472c;
  --accent-soft: #f6e7e2;
  --ok: #2f7d51;
  --ok-soft: #e4f2ea;
  --bad: #b3352d;
  --bad-soft: #fae7e5;
  --warn: #96700f;
  --radius: 12px;
  --mono: ui-monospace, "SF Mono", Menlo, monospace;
  color-scheme: light dark;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #101418; --panel: #171c22; --panel-2: #1e242b; --ink: #e8eaed;
    --ink-dim: #98a1ae; --line: #2a323b; --accent: #e0704f; --accent-soft: #2a1c18;
    --ok: #6cc48d; --ok-soft: #16261d; --bad: #ef8378; --bad-soft: #2a1817; --warn: #d5aa4a;
  }
}
* { box-sizing: border-box; }
html, body { margin: 0; padding: 0; }
body {
  background: var(--bg); color: var(--ink);
  font: 15px/1.5 -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  -webkit-text-size-adjust: 100%;
}
button, input, select, textarea { font: inherit; color: inherit; }
a { color: var(--accent); text-decoration: none; }

.app { max-width: 980px; margin: 0 auto; padding: 0 16px 96px; }

.topbar { display: flex; align-items: center; justify-content: space-between; gap: 12px; padding: 14px 0 8px; }
.brand { background: none; border: 0; padding: 0; font-size: 17px; font-weight: 650; letter-spacing: -.01em; cursor: pointer; }
.brand span { color: var(--ink-dim); font-weight: 400; }
.topbar-meta { color: var(--ink-dim); font-size: 13px; display: flex; gap: 10px; align-items: center; }

.nav { display: flex; gap: 2px; overflow-x: auto; scrollbar-width: none; border-bottom: 1px solid var(--line); margin-bottom: 18px; }
.nav::-webkit-scrollbar { display: none; }
.nav a {
  padding: 9px 12px; color: var(--ink-dim); white-space: nowrap; font-size: 14px;
  border-bottom: 2px solid transparent; margin-bottom: -1px;
}
.nav a.active { color: var(--ink); border-bottom-color: var(--accent); font-weight: 550; }

.card { background: var(--panel); border: 1px solid var(--line); border-radius: var(--radius); padding: 16px; }
.grid { display: grid; gap: 12px; }
.grid.two { grid-template-columns: repeat(auto-fit, minmax(260px, 1fr)); }
.grid.three { grid-template-columns: repeat(auto-fit, minmax(190px, 1fr)); }
.stack { display: flex; flex-direction: column; gap: 12px; }
.row { display: flex; gap: 8px; align-items: center; flex-wrap: wrap; }
.spread { display: flex; justify-content: space-between; align-items: baseline; gap: 8px; }

h1 { font-size: 22px; margin: 0 0 4px; letter-spacing: -.015em; }
h2 { font-size: 15px; margin: 0 0 10px; text-transform: uppercase; letter-spacing: .06em; color: var(--ink-dim); font-weight: 600; }
h3 { font-size: 15px; margin: 0 0 6px; }
p { margin: 0 0 8px; }
.dim { color: var(--ink-dim); }
.small { font-size: 13px; }
.tiny { font-size: 12px; }
.tr { font-family: var(--mono); }
.big-number { font-size: 30px; font-weight: 650; letter-spacing: -.02em; line-height: 1.1; }

.btn {
  background: var(--panel-2); border: 1px solid var(--line); border-radius: 9px;
  padding: 9px 14px; cursor: pointer; font-weight: 520;
}
.btn:hover { border-color: var(--ink-dim); }
.btn.primary { background: var(--accent); border-color: var(--accent); color: #fff; }
.btn.ghost { background: none; }
.btn.wide { width: 100%; justify-content: center; }
.btn:disabled { opacity: .5; cursor: default; }

.pill { display: inline-flex; align-items: center; gap: 5px; padding: 2px 9px; border-radius: 999px; font-size: 12px; background: var(--panel-2); border: 1px solid var(--line); }
.pill.ok { background: var(--ok-soft); border-color: transparent; color: var(--ok); }
.pill.bad { background: var(--bad-soft); border-color: transparent; color: var(--bad); }
.pill.accent { background: var(--accent-soft); border-color: transparent; color: var(--accent); }

.bar { height: 6px; border-radius: 3px; background: var(--panel-2); overflow: hidden; }
.bar > i { display: block; height: 100%; background: var(--accent); }
.bar.ok > i { background: var(--ok); }

.levels { display: flex; gap: 2px; }
.levels i { width: 12px; height: 6px; border-radius: 2px; background: var(--panel-2); }
.levels i.on { background: var(--accent); }
.levels i.on.fluent { background: var(--ok); }

table { width: 100%; border-collapse: collapse; font-size: 14px; }
th { text-align: left; font-weight: 600; color: var(--ink-dim); font-size: 12px; text-transform: uppercase; letter-spacing: .05em; padding: 6px 8px; border-bottom: 1px solid var(--line); }
td { padding: 8px; border-bottom: 1px solid var(--line); vertical-align: top; }
tr:last-child td { border-bottom: 0; }
.scroll-x { overflow-x: auto; }

/* ------------------------------------------------------------------ drill */
.drill { max-width: 620px; margin: 0 auto; }
.drill-progress { display: flex; align-items: center; gap: 10px; margin-bottom: 18px; }
.drill-progress .bar { flex: 1; }
.prompt-card { padding: 22px 18px; text-align: center; }
.prompt-reason { font-size: 12px; color: var(--ink-dim); margin-bottom: 10px; }
.prompt-de { font-size: 22px; font-weight: 550; line-height: 1.35; letter-spacing: -.01em; }
.prompt-base { font-family: var(--mono); font-size: 15px; color: var(--ink-dim); margin-top: 8px; }
.prompt-hint { font-size: 13px; color: var(--ink-dim); margin-top: 10px; }

.answer-input {
  width: 100%; padding: 14px 14px; font-size: 19px; font-family: var(--mono);
  background: var(--panel); border: 1px solid var(--line); border-radius: 10px; outline: none;
}
.answer-input:focus { border-color: var(--accent); }
.charbar { display: flex; gap: 6px; flex-wrap: wrap; margin-top: 8px; }
.charbar button { min-width: 40px; padding: 9px 0; font-family: var(--mono); font-size: 16px; background: var(--panel-2); border: 1px solid var(--line); border-radius: 8px; cursor: pointer; flex: 1; }

.options { display: grid; gap: 8px; grid-template-columns: 1fr 1fr; }
@media (max-width: 480px) { .options { grid-template-columns: 1fr; } }
.option {
  padding: 15px 12px; font-family: var(--mono); font-size: 17px; text-align: center;
  background: var(--panel); border: 1px solid var(--line); border-radius: 10px; cursor: pointer;
}
.option:hover { border-color: var(--accent); }
.option kbd { font-size: 11px; color: var(--ink-dim); margin-right: 6px; font-family: var(--mono); }

.bank { display: flex; flex-wrap: wrap; gap: 8px; }
.bank button { padding: 11px 13px; font-family: var(--mono); font-size: 16px; background: var(--panel-2); border: 1px solid var(--line); border-radius: 9px; cursor: pointer; }
.bank button.used { opacity: .35; }
.assembled { min-height: 52px; padding: 12px; border: 1px dashed var(--line); border-radius: 10px; font-family: var(--mono); font-size: 18px; display: flex; flex-wrap: wrap; gap: 8px; align-items: center; }
.assembled button { background: var(--accent-soft); border: 1px solid transparent; border-radius: 7px; padding: 5px 9px; font-family: var(--mono); font-size: 16px; cursor: pointer; color: var(--ink); }

.feedback { border-radius: var(--radius); padding: 14px 16px; }
.feedback.ok { background: var(--ok-soft); }
.feedback.bad { background: var(--bad-soft); }
.feedback .line { display: flex; gap: 10px; align-items: baseline; }
.feedback .label { font-size: 12px; text-transform: uppercase; letter-spacing: .05em; color: var(--ink-dim); min-width: 92px; }
.feedback .value { font-family: var(--mono); font-size: 18px; }
.feedback .value.strike { text-decoration: line-through; text-decoration-thickness: 1px; opacity: .8; }
.feedback .why { margin-top: 10px; font-size: 14px; }

.chat { display: flex; flex-direction: column; gap: 10px; }
.msg { padding: 11px 14px; border-radius: 12px; max-width: 88%; white-space: pre-wrap; }
.msg.user { align-self: flex-end; background: var(--accent-soft); }
.msg.assistant { align-self: flex-start; background: var(--panel); border: 1px solid var(--line); }

.spark { display: flex; align-items: flex-end; gap: 3px; height: 44px; }
.spark i { flex: 1; background: var(--accent); border-radius: 2px 2px 0 0; min-height: 2px; opacity: .85; }
.spark i.empty { background: var(--line); }

.list-item { display: flex; justify-content: space-between; gap: 12px; padding: 10px 0; border-bottom: 1px solid var(--line); }
.list-item:last-child { border-bottom: 0; }
.clickable { cursor: pointer; }
.empty-state { text-align: center; padding: 40px 20px; color: var(--ink-dim); }
.kbd-hint { font-size: 12px; color: var(--ink-dim); text-align: center; margin-top: 14px; }
@media (max-width: 600px) { .kbd-hint { display: none; } }