:root {
  color-scheme: dark;
  --bg: #0a0d14;
  --bg-soft: #111725;
  --card: rgba(18, 24, 38, 0.86);
  --card-strong: rgba(25, 33, 52, 0.96);
  --line: rgba(201, 213, 255, 0.14);
  --line-strong: rgba(146, 163, 255, 0.32);
  --text: #f5f7ff;
  --muted: #aab4cc;
  --soft: #d8dded;
  --accent: #8ea2ff;
  --accent-2: #75e0c1;
  --warm: #f7c873;
  --danger: #ff8f8f;
  --shadow: 0 28px 90px rgba(0, 0, 0, 0.42);
}

* { box-sizing: border-box; }

html { min-height: 100%; }

body {
  margin: 0;
  min-height: 100vh;
  background:
    radial-gradient(circle at 12% 4%, rgba(142, 162, 255, 0.28), transparent 34rem),
    radial-gradient(circle at 86% 10%, rgba(117, 224, 193, 0.18), transparent 28rem),
    linear-gradient(135deg, #070a11 0%, #111525 54%, #080a10 100%);
  color: var(--text);
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
}

body::before {
  content: "";
  position: fixed;
  inset: 0;
  pointer-events: none;
  background-image: linear-gradient(rgba(255,255,255,0.025) 1px, transparent 1px), linear-gradient(90deg, rgba(255,255,255,0.018) 1px, transparent 1px);
  background-size: 48px 48px;
  mask-image: linear-gradient(to bottom, rgba(0,0,0,0.8), transparent 74%);
}

button, textarea { font: inherit; }

button {
  border: 1px solid var(--line);
  border-radius: 16px;
  background: rgba(255, 255, 255, 0.055);
  color: var(--text);
  cursor: pointer;
  transition: transform 150ms ease, border-color 150ms ease, background 150ms ease, box-shadow 150ms ease;
}

button:hover { transform: translateY(-1px); border-color: var(--line-strong); background: rgba(255,255,255,0.085); }
button:focus-visible, textarea:focus-visible { outline: 3px solid rgba(142, 162, 255, 0.42); outline-offset: 2px; }
button:disabled { opacity: 0.58; cursor: progress; transform: none; }

.app-shell {
  width: min(1180px, 100%);
  margin: 0 auto;
  padding: 28px 16px 54px;
  position: relative;
}

.hero {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 18px;
  align-items: end;
  margin-bottom: 22px;
}

@media (min-width: 880px) {
  .hero { grid-template-columns: minmax(0, 1.35fr) minmax(280px, 0.65fr); }
}

.eyebrow, .panel-label, .step-label, .section-heading span, .phrase-title, .meaning-grid span, .model-card span, .deepseek-card span {
  color: var(--accent-2);
  font-size: 0.74rem;
  font-weight: 800;
  letter-spacing: 0.13em;
  text-transform: uppercase;
}

h1, h2, p { margin-top: 0; }

h1 {
  max-width: 780px;
  margin-bottom: 12px;
  font-size: clamp(2.55rem, 8vw, 6.25rem);
  line-height: 0.92;
  letter-spacing: -0.075em;
}

h2 {
  margin-bottom: 6px;
  font-size: clamp(1.1rem, 3vw, 1.55rem);
  letter-spacing: -0.035em;
}

.hero-lede {
  max-width: 720px;
  color: var(--soft);
  font-size: clamp(1rem, 2.2vw, 1.25rem);
  line-height: 1.55;
}

.hero-panel, .side-card, .lesson-card, .answer-card, .saved-card {
  border: 1px solid var(--line);
  border-radius: 28px;
  background: var(--card);
  box-shadow: var(--shadow);
  backdrop-filter: blur(18px);
}

.hero-panel { padding: 22px; }
.hero-panel strong { display: block; margin: 8px 0; font-size: 1.55rem; letter-spacing: -0.04em; }
.hero-panel p, .lesson-topline p, .empty-note { color: var(--muted); line-height: 1.55; margin-bottom: 0; }

.practice-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 16px;
}

@media (min-width: 980px) {
  .practice-layout {
    grid-template-columns: 280px minmax(0, 1fr);
    align-items: start;
  }
  .side-card, .saved-card { position: sticky; top: 18px; }
  .answer-card, .saved-card { grid-column: 2; }
}

.side-card, .lesson-card, .answer-card, .saved-card { padding: 18px; }
.lesson-card { background: var(--card-strong); }

.section-heading { margin-bottom: 14px; }
.section-heading h2 { margin-bottom: 0; }

.language-list { display: grid; gap: 10px; }

.language-option {
  display: grid;
  grid-template-columns: 46px 1fr;
  gap: 12px;
  align-items: center;
  width: 100%;
  padding: 12px;
  text-align: left;
}
.language-option.active { border-color: rgba(117,224,193,0.72); background: rgba(117,224,193,0.13); box-shadow: 0 0 0 1px rgba(117,224,193,0.12) inset; }
.language-code {
  display: grid;
  place-items: center;
  width: 42px;
  height: 42px;
  border-radius: 14px;
  background: rgba(142,162,255,0.14);
  color: var(--accent);
  font-weight: 900;
}
.language-option small { display: block; color: var(--muted); margin-top: 2px; line-height: 1.3; }

.mini-stat {
  margin-top: 16px;
  padding: 14px;
  border-radius: 18px;
  background: rgba(255,255,255,0.045);
  border: 1px solid var(--line);
}
.mini-stat span { font-size: 2.1rem; font-weight: 900; color: var(--warm); }
.mini-stat p { margin-bottom: 0; color: var(--muted); }

.lesson-topline { display: flex; justify-content: space-between; gap: 14px; align-items: start; }
.progress-pill { flex: 0 0 auto; padding: 8px 12px; border-radius: 999px; color: var(--warm); border: 1px solid rgba(247,200,115,0.28); background: rgba(247,200,115,0.09); font-weight: 800; }
.progress-track { height: 7px; margin: 14px 0 20px; border-radius: 999px; background: rgba(255,255,255,0.075); overflow: hidden; }
.progress-track span { display: block; height: 100%; border-radius: inherit; background: linear-gradient(90deg, var(--accent), var(--accent-2)); }

.phrase-stage {
  margin: 18px 0;
  padding: clamp(18px, 5vw, 34px);
  border: 1px solid rgba(142,162,255,0.2);
  border-radius: 28px;
  background:
    radial-gradient(circle at top right, rgba(142,162,255,0.18), transparent 58%),
    rgba(3, 6, 14, 0.35);
}
.native-line {
  margin: 8px 0 10px;
  font-size: clamp(2.3rem, 10vw, 5.8rem);
  line-height: 1.02;
  letter-spacing: -0.05em;
  overflow-wrap: anywhere;
}
.sound-line { color: var(--warm); font-size: clamp(1rem, 2.2vw, 1.25rem); line-height: 1.45; }
.sound-help { margin-top: 8px; color: var(--muted); }

.meaning-grid {
  display: grid;
  gap: 10px;
  grid-template-columns: minmax(0, 1fr);
}
@media (min-width: 720px) { .meaning-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); } }
.meaning-grid div, .coach-note, .model-card, .deepseek-card {
  border: 1px solid var(--line);
  border-radius: 18px;
  background: rgba(255,255,255,0.045);
  padding: 14px;
}
.meaning-grid p, .coach-note, .model-card p, .deepseek-card p { color: var(--soft); line-height: 1.55; margin-bottom: 0; }
.coach-note { margin-top: 12px; border-color: rgba(117,224,193,0.2); }

.answer-card label { display: block; color: var(--soft); font-weight: 800; margin-bottom: 10px; }
textarea {
  width: 100%;
  min-height: 138px;
  resize: vertical;
  border: 1px solid var(--line);
  border-radius: 20px;
  background: rgba(3, 6, 14, 0.5);
  color: var(--text);
  padding: 14px;
  line-height: 1.55;
}
textarea::placeholder { color: rgba(170,180,204,0.72); }
.action-row { display: flex; flex-wrap: wrap; gap: 10px; margin-top: 12px; }
.action-row button { padding: 12px 14px; font-weight: 800; }
.primary-action { background: linear-gradient(135deg, var(--accent), var(--accent-2)); border-color: transparent; color: #071018; }
.deepseek-action { border-color: rgba(142,162,255,0.42); background: rgba(142,162,255,0.13); }
.model-card, .deepseek-card { margin-top: 14px; }
.deepseek-card { border-color: rgba(142,162,255,0.28); }
.deepseek-card ul { margin: 10px 0 0; padding-left: 20px; color: var(--soft); line-height: 1.55; }
.deepseek-card .error { color: var(--danger); }

.saved-card ul { list-style: none; display: grid; gap: 10px; padding: 0; margin: 0; }
.saved-card li {
  display: grid;
  grid-template-columns: 42px 1fr;
  gap: 10px;
  padding: 12px;
  border-radius: 16px;
  background: rgba(255,255,255,0.045);
  border: 1px solid var(--line);
}
.saved-card li > span {
  display: grid;
  place-items: center;
  width: 36px;
  height: 36px;
  border-radius: 12px;
  background: rgba(247,200,115,0.12);
  color: var(--warm);
  font-weight: 900;
}
.saved-card p { color: var(--muted); margin: 4px 0 0; line-height: 1.4; }

@media (max-width: 520px) {
  .app-shell { padding: 22px 12px 38px; }
  .hero-panel, .side-card, .lesson-card, .answer-card, .saved-card { border-radius: 22px; }
  .lesson-topline { display: grid; }
  .action-row button { width: 100%; text-align: center; }
}