* { box-sizing: border-box; }
:root {
  --bg: #0f1115;
  --panel: #181b22;
  --panel-2: #1f232c;
  --text: #e8ebf0;
  --muted: #8b93a3;
  --accent: #6aa9ff;
  --accent-2: #7ee0c6;
  --warn: #ffb86b;
  --bad: #ff6b8a;
  --border: #2a2f3a;
}
body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.5;
}
header.topbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 10px;
  padding: 16px 24px;
  border-bottom: 1px solid var(--border);
}
header.topbar h1 { font-size: 18px; margin: 0; }
header.topbar nav { display: flex; align-items: center; flex-wrap: wrap; gap: 8px 16px; }
nav a { color: var(--muted); text-decoration: none; font-size: 14px; padding: 6px 0; }
nav a:hover { color: var(--text); }
.lang-switcher { display: inline-flex; gap: 2px; background: var(--panel-2); border: 1px solid var(--border); border-radius: 999px; padding: 2px; }
.lang-switcher button { background: transparent; color: var(--muted); border: none; padding: 8px 12px; border-radius: 999px; font-size: 12px; font-weight: 600; cursor: pointer; min-height: 36px; }
.lang-switcher button.active { background: var(--accent); color: #0a0d12; }
.voice-switcher-wrap { display: inline-flex; gap: 4px; align-items: center; }
.voice-switcher { background: var(--panel-2); color: var(--text); border: 1px solid var(--border); border-radius: 8px; padding: 8px; font-size: 12px; max-width: 40vw; }
.voice-preview { background: var(--panel-2); color: var(--muted); border: 1px solid var(--border); border-radius: 6px; padding: 7px 10px; font-size: 11px; cursor: pointer; min-height: 36px; }
.voice-preview:hover { color: var(--accent); border-color: var(--accent); }
.voice-preview:disabled { cursor: wait; }
.tts-controls { display: inline-flex; gap: 8px; align-items: center; font-size: 12px; color: var(--muted); }
.tts-auto { cursor: pointer; user-select: none; padding: 6px 0; }
.tts-auto input { vertical-align: middle; margin-right: 2px; width: 18px; height: 18px; }
.tts-counter { background: var(--panel-2); border: 1px solid var(--border); padding: 6px 10px; border-radius: 999px; cursor: pointer; }
.tts-counter:hover { color: var(--text); border-color: var(--accent); }
#toastBox {
  position: fixed; top: 20px; right: 20px; z-index: 9999;
  background: var(--panel); color: var(--text);
  border: 1px solid var(--border); border-radius: 10px;
  padding: 14px 18px; max-width: min(380px, calc(100vw - 40px));
  box-shadow: 0 10px 30px rgba(0,0,0,0.4);
  opacity: 0; transform: translateY(-10px); pointer-events: none;
  transition: opacity 0.2s, transform 0.2s;
  font-size: 14px; line-height: 1.4;
}
#toastBox.show { opacity: 1; transform: translateY(0); pointer-events: auto; }
#toastBox.warn { border-color: var(--warn); }
#toastBox.error { border-color: var(--bad); }
main { max-width: 900px; margin: 0 auto; padding: 24px; }
.card {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 20px;
  margin-bottom: 16px;
}
.card h2 { margin: 0 0 12px; font-size: 16px; color: var(--muted); text-transform: uppercase; letter-spacing: 0.05em; }
.row { display: flex; gap: 12px; align-items: center; flex-wrap: wrap; }
button {
  background: var(--accent);
  color: #0a0d12;
  border: none;
  padding: 12px 18px;
  border-radius: 8px;
  font-weight: 600;
  cursor: pointer;
  font-size: 14px;
  min-height: 44px;
}
button.secondary { background: var(--panel-2); color: var(--text); border: 1px solid var(--border); }
button.ghost { background: transparent; color: var(--muted); border: 1px solid var(--border); }
button:disabled { opacity: 0.5; cursor: not-allowed; }
button.mic { width: 64px; height: 64px; border-radius: 50%; font-size: 24px; padding: 0; }
button.mic.recording { background: var(--bad); color: #fff; animation: pulse 1s infinite; }
@keyframes pulse { 0%,100%{transform:scale(1)} 50%{transform:scale(1.06)} }
.expr-list { list-style: none; padding: 0; margin: 0; }
.expr-list li {
  border-top: 1px solid var(--border);
  padding: 12px 0;
  display: flex; justify-content: space-between; gap: 12px;
}
.expr-list li:first-child { border-top: none; }
.expr-en { font-weight: 600; }
.expr-ko { color: var(--muted); font-size: 13px; }
.fav { background: transparent; border: none; color: var(--muted); cursor: pointer; font-size: 18px; padding: 8px; min-width: 40px; min-height: 40px; }
.fav.active { color: var(--warn); }
.chip {
  display: inline-block;
  background: var(--panel-2);
  padding: 4px 10px;
  border-radius: 999px;
  font-size: 12px;
  color: var(--muted);
  margin-right: 6px;
}
.chip.level { color: var(--accent-2); }
.day-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(140px, 1fr)); gap: 8px; }
.day-grid a {
  background: var(--panel-2);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 10px;
  font-size: 13px;
  text-decoration: none;
  color: var(--text);
}
.day-grid a.done { border-color: var(--accent-2); }
.day-grid a:hover { background: #262b35; }
.transcript { max-height: 320px; overflow-y: auto; padding: 8px 0; }
.bubble {
  padding: 10px 14px; border-radius: 14px; margin: 6px 0;
  max-width: 80%; word-wrap: break-word; white-space: pre-wrap;
}
.bubble.user { background: var(--accent); color: #0a0d12; margin-left: auto; }
.bubble.assistant { background: var(--panel-2); }
.bubble.system { background: transparent; color: var(--muted); font-style: italic; }
.stage-pill {
  display: inline-block; padding: 10px 14px; border-radius: 6px;
  background: var(--panel-2); font-size: 13px; color: var(--muted); margin: 0 6px 6px 0;
  cursor: pointer; user-select: none; border: 1px solid var(--border);
}
.stage-pill:hover { color: var(--text); }
.stage-pill.active { background: var(--accent); color: #0a0d12; border-color: var(--accent); }
.feedback-block { background: var(--panel-2); padding: 12px; border-radius: 8px; margin-top: 12px; }
.feedback-block .rubric { display: grid; grid-template-columns: repeat(auto-fit, minmax(150px, 1fr)); gap: 8px; margin-top: 8px; }
.feedback-block .rubric div { font-size: 13px; }
.score { font-weight: 700; color: var(--accent-2); }
.correction { border-left: 3px solid var(--warn); padding: 6px 10px; margin: 6px 0; background: #1a1d24; }
.correction del { color: var(--bad); }
.correction ins { color: var(--accent-2); text-decoration: none; font-weight: 600; }
.hint { color: var(--muted); font-size: 13px; margin-top: 8px; }
input[type=text], textarea {
  width: 100%; background: var(--panel-2); color: var(--text);
  border: 1px solid var(--border); border-radius: 8px; padding: 10px; font: inherit;
}
.stat { display: inline-block; margin-right: 24px; }
.stat .n { font-size: 28px; font-weight: 700; color: var(--accent-2); }
.stat .label { color: var(--muted); font-size: 12px; text-transform: uppercase; letter-spacing: 0.05em; }

/* ============ mobile ============ */
@media (max-width: 640px) {
  header.topbar { padding: 12px 14px; gap: 8px; }
  header.topbar h1 { font-size: 16px; }
  header.topbar nav { gap: 6px 12px; width: 100%; }
  nav a { font-size: 13px; }
  main { padding: 14px; }
  .card { padding: 14px; margin-bottom: 12px; }
  .card h2 { font-size: 15px; }
  .transcript { max-height: 50vh; }
  .bubble { max-width: 88%; }
  .stat { margin-right: 16px; }
  .stat .n { font-size: 22px; }
  .day-grid { grid-template-columns: repeat(auto-fill, minmax(110px, 1fr)); }
  #toastBox { top: 12px; right: 12px; left: 12px; max-width: none; }
  .voice-switcher { max-width: 32vw; }
}