:root {
  --bg: #0f1220;
  --bg2: #171b2e;
  --card: #1c2138;
  --line: #2a3050;
  --text: #eef0fa;
  --muted: #9aa1c4;
  --accent: #7c6cff;
  --accent2: #38d6b0;
  --danger: #ff5d6c;
  --radius: 18px;
}
@media (prefers-color-scheme: light) {
  :root {
    --bg: #f4f5fb; --bg2: #ffffff; --card: #ffffff; --line: #e1e4f2;
    --text: #1c2038; --muted: #6a7096; --accent: #6552f5; --accent2: #12a98a; --danger: #e5384b;
  }
}
* { box-sizing: border-box; -webkit-tap-highlight-color: transparent; }
html, body { margin: 0; height: 100%; }
body {
  background: radial-gradient(1200px 600px at 50% -10%, color-mix(in srgb, var(--accent) 18%, var(--bg)), var(--bg));
  color: var(--text);
  font: 16px/1.5 system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
}
.app { max-width: 720px; margin: 0 auto; min-height: 100%; display: flex; flex-direction: column; padding: 0 16px 24px; }

header { display: flex; align-items: center; justify-content: space-between; padding: 16px 0 8px; }
.brand { font-weight: 700; font-size: 18px; letter-spacing: .2px; }
.brand span { color: var(--accent2); }
.link { background: none; border: 0; color: var(--muted); cursor: pointer; font: inherit; font-size: 14px; }
.link:hover { color: var(--text); }

nav { display: flex; gap: 6px; background: var(--bg2); border: 1px solid var(--line); border-radius: 999px; padding: 4px; margin: 8px 0 20px; }
nav button { flex: 1; border: 0; background: none; color: var(--muted); padding: 10px 8px; border-radius: 999px; font: inherit; font-weight: 600; cursor: pointer; }
nav button.on { background: var(--accent); color: #fff; }

.view { display: none; }
.view.on { display: block; }

/* Talk */
.talk { text-align: center; padding-top: 6px; }
.orb-wrap { position: relative; width: 240px; height: 240px; margin: 18px auto 14px; display: grid; place-items: center; }
.orb {
  --lvl: 0; --c1: var(--accent); --c2: #b7aeff;
  width: 160px; height: 160px; border-radius: 50%;
  background: radial-gradient(circle at 32% 28%, var(--c2), var(--c1) 62%);
  box-shadow: 0 0 calc(30px + var(--lvl) * 90px) color-mix(in srgb, var(--c1) 70%, transparent);
  transform: scale(calc(1 + var(--lvl) * .35));
  transition: transform .08s linear, box-shadow .08s linear, background .4s;
}
.orb.idle { animation: breathe 4s ease-in-out infinite; opacity: .75; }
.orb.user { --c1: var(--accent2); --c2: #a8f5df; }
@keyframes breathe { 50% { transform: scale(1.05); } }
.status { min-height: 28px; font-size: 18px; font-weight: 600; }
.sub { color: var(--muted); font-size: 14px; min-height: 22px; }
.timer { font-variant-numeric: tabular-nums; color: var(--muted); margin-top: 4px; }

.big {
  margin: 22px auto 8px; display: block; width: min(320px, 100%); border: 0; cursor: pointer;
  padding: 16px 22px; border-radius: 999px; font: inherit; font-size: 18px; font-weight: 700; color: #fff;
  background: linear-gradient(135deg, var(--accent), color-mix(in srgb, var(--accent) 60%, var(--accent2)));
  box-shadow: 0 10px 30px color-mix(in srgb, var(--accent) 40%, transparent);
}
.big:disabled { opacity: .6; cursor: default; }
.big.stop { background: var(--danger); box-shadow: 0 10px 30px color-mix(in srgb, var(--danger) 40%, transparent); }

.toggle { display: inline-flex; align-items: center; gap: 8px; color: var(--muted); font-size: 14px; cursor: pointer; margin-top: 10px; }
.captions { margin: 18px auto 0; text-align: left; max-height: 240px; overflow-y: auto; display: none; }
.captions.on { display: block; }
.cap { padding: 8px 12px; border-radius: 12px; margin: 6px 0; font-size: 15px; }
.cap.user { background: color-mix(in srgb, var(--accent2) 16%, transparent); }
.cap.assistant { background: color-mix(in srgb, var(--accent) 18%, transparent); }
.tip { color: var(--muted); font-size: 13px; margin-top: 18px; }
.err { color: var(--danger); font-size: 14px; min-height: 20px; margin-top: 8px; }

/* Cards, forms */
.card { background: var(--card); border: 1px solid var(--line); border-radius: var(--radius); padding: 16px; }
.field { margin-bottom: 16px; }
.field label { display: block; font-weight: 600; margin-bottom: 4px; }
.field .hint { color: var(--muted); font-size: 13px; margin-bottom: 6px; }
input[type=text], input[type=password], select, textarea {
  width: 100%; padding: 12px 14px; border-radius: 12px; border: 1px solid var(--line);
  background: var(--bg2); color: var(--text); font: inherit;
}
textarea { min-height: 84px; resize: vertical; }
.row2 { display: grid; grid-template-columns: 1fr 1fr; gap: 12px; }
@media (max-width: 520px) { .row2 { grid-template-columns: 1fr; } }
.btn { border: 0; border-radius: 12px; padding: 12px 18px; font: inherit; font-weight: 700; cursor: pointer; background: var(--accent); color: #fff; }
.btn.ghost { background: transparent; border: 1px solid var(--line); color: var(--text); }
.btn.danger { background: transparent; border: 1px solid var(--danger); color: var(--danger); }
.saved { color: var(--accent2); margin-left: 10px; font-weight: 600; }

/* History */
.day { margin: 20px 0 8px; color: var(--muted); font-weight: 700; font-size: 13px; text-transform: uppercase; letter-spacing: .6px; }
.item { display: block; width: 100%; text-align: left; background: var(--card); border: 1px solid var(--line); color: var(--text); border-radius: 14px; padding: 12px 14px; margin-bottom: 8px; cursor: pointer; font: inherit; }
.item:hover { border-color: var(--accent); }
.item .t { font-weight: 600; white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
.item .m { color: var(--muted); font-size: 13px; margin-top: 2px; }
.chip { display: inline-block; background: color-mix(in srgb, var(--accent) 20%, transparent); color: var(--text); border-radius: 999px; padding: 1px 8px; font-size: 12px; margin-right: 6px; }
.empty { color: var(--muted); text-align: center; padding: 40px 0; }
.bubble { max-width: 86%; padding: 10px 14px; border-radius: 16px; margin: 8px 0; }
.bubble.user { margin-left: auto; background: color-mix(in srgb, var(--accent2) 22%, transparent); border-bottom-right-radius: 4px; }
.bubble.assistant { margin-right: auto; background: color-mix(in srgb, var(--accent) 22%, transparent); border-bottom-left-radius: 4px; }
.bubble small { display: block; color: var(--muted); font-size: 11px; margin-top: 2px; }
.detail-head { display: flex; justify-content: space-between; align-items: center; gap: 8px; margin-bottom: 8px; }

/* Login */
.login { max-width: 360px; margin: 14vh auto 0; padding: 0 16px; text-align: center; }
.login h1 { margin: 0 0 6px; }
.login p { color: var(--muted); margin: 0 0 20px; }
.login input { margin-bottom: 12px; text-align: center; }
.login .btn { width: 100%; }

/* Pronunciation score card (Talk screen) */
.score { display: flex; align-items: center; gap: 14px; text-align: left; margin: 16px auto 0; max-width: 420px; background: var(--card); border: 1px solid var(--line); border-radius: var(--radius); padding: 12px 16px; }
.score .num { font-size: 40px; font-weight: 800; line-height: 1; min-width: 64px; text-align: center; font-variant-numeric: tabular-nums; }
.score .num.good { color: var(--accent2); }
.score .num.ok { color: #f0a82a; }
.score .num.low { color: var(--danger); }
.score .lab { font-size: 13px; color: var(--muted); font-weight: 600; }
.score .words { margin-top: 4px; font-size: 14px; }
.score .words span { display: inline-block; background: color-mix(in srgb, var(--danger) 18%, transparent); border-radius: 999px; padding: 1px 9px; margin: 2px 4px 2px 0; font-size: 13px; }
.score .words .okmsg { background: color-mix(in srgb, var(--accent2) 18%, transparent); }
.score .avg { margin-top: 4px; font-size: 13px; color: var(--muted); }