:root {
  --bg-main: #0b1f16;
  --bg-card: #132820;
  --accent-rose: #ff6b9c;
  --accent-fruit: #ffb347;
  --accent-leaf: #4caf50;
  --text-main: #fdfdfd;
  --text-muted: #c7d5cc;
  --border-soft: rgba(255, 255, 255, 0.08);
  --shadow-soft: 0 18px 40px rgba(0, 0, 0, 0.55);
  --radius-card: 18px;
  --radius-pill: 999px;
  --transition-fast: 0.18s ease-out;
  --font-main: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

body {
  margin: 0;
  min-height: 100vh;
  font-family: var(--font-main);
  color: var(--text-main);
  background:
    radial-gradient(circle at 10% 0%, rgba(255, 107, 156, 0.18), transparent 55%),
    radial-gradient(circle at 90% 100%, rgba(255, 179, 71, 0.18), transparent 55%),
    radial-gradient(circle at 50% 100%, rgba(76, 175, 80, 0.18), transparent 55%),
    linear-gradient(145deg, #050b08, #07110c 40%, #020605);
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 24px;
}

/* Main layout card */

.app-shell {
  width: 100%;
  max-width: 960px;
  background: radial-gradient(circle at top left, rgba(255, 107, 156, 0.12), transparent 55%),
              radial-gradient(circle at bottom right, rgba(76, 175, 80, 0.12), transparent 55%),
              var(--bg-card);
  border-radius: 28px;
  box-shadow: var(--shadow-soft);
  border: 1px solid var(--border-soft);
  padding: 24px 26px 20px;
  position: relative;
  overflow: hidden;
}

/* Decorative vines / roses */

.app-shell::before,
.app-shell::after {
  content: "";
  position: absolute;
  pointer-events: none;
  opacity: 0.55;
  filter: blur(0.3px);
}

.app-shell::before {
  top: -40px;
  left: -60px;
  width: 220px;
  height: 220px;
  background:
    radial-gradient(circle at 20% 20%, rgba(255, 107, 156, 0.9), transparent 55%),
    radial-gradient(circle at 70% 70%, rgba(76, 175, 80, 0.9), transparent 55%);
  mix-blend-mode: screen;
}

.app-shell::after {
  bottom: -40px;
  right: -60px;
  width: 260px;
  height: 260px;
  background:
    radial-gradient(circle at 30% 30%, rgba(255, 179, 71, 0.9), transparent 55%),
    radial-gradient(circle at 80% 80%, rgba(76, 175, 80, 0.9), transparent 55%);
  mix-blend-mode: screen;
}

/* Header */

.app-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  margin-bottom: 18px;
  position: relative;
  z-index: 1;
}

.brand-block {
  display: flex;
  align-items: center;
  gap: 12px;
}

.brand-icon {
  width: 40px;
  height: 40px;
  border-radius: 14px;
  background:
    radial-gradient(circle at 30% 20%, #ff6b9c, transparent 60%),
    radial-gradient(circle at 70% 80%, #4caf50, transparent 60%);
  border: 1px solid rgba(255, 255, 255, 0.35);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 22px;
}

.brand-text-main {
  font-weight: 600;
  letter-spacing: 0.03em;
  font-size: 18px;
}

.brand-text-sub {
  font-size: 12px;
  color: var(--text-muted);
}

/* Language toggle */

.lang-toggle {
  display: inline-flex;
  align-items: center;
  background: rgba(5, 12, 9, 0.9);
  border-radius: var(--radius-pill);
  border: 1px solid var(--border-soft);
  padding: 3px;
  gap: 3px;
}

.lang-btn {
  border: none;
  background: transparent;
  color: var(--text-muted);
  font-size: 12px;
  padding: 6px 12px;
  border-radius: var(--radius-pill);
  cursor: pointer;
  transition: background var(--transition-fast), color var(--transition-fast), transform var(--transition-fast);
}

.lang-btn.active {
  background: linear-gradient(135deg, var(--accent-rose), var(--accent-fruit));
  color: #050806;
  font-weight: 600;
  transform: translateY(-1px);
}

/* Content layout */

.app-content {
  display: grid;
  grid-template-columns: minmax(0, 3fr) minmax(0, 2fr);
  gap: 18px;
  position: relative;
  z-index: 1;
}

@media (max-width: 768px) {
  .app-shell {
    padding: 18px 16px 16px;
  }
  .app-content {
    grid-template-columns: 1fr;
  }
}

/* Lesson card */

.card {
  background: rgba(5, 12, 9, 0.92);
  border-radius: var(--radius-card);
  border: 1px solid var(--border-soft);
  padding: 16px 16px 14px;
  position: relative;
  overflow: hidden;
}

.card::before {
  content: "";
  position: absolute;
  inset: 0;
  background:
    linear-gradient(135deg, rgba(255, 107, 156, 0.08), transparent 55%),
    linear-gradient(315deg, rgba(76, 175, 80, 0.08), transparent 55%);
  opacity: 0.9;
  pointer-events: none;
}

.card-inner {
  position: relative;
  z-index: 1;
}

.card-title {
  font-size: 16px;
  font-weight: 600;
  margin-bottom: 6px;
  display: flex;
  align-items: center;
  gap: 8px;
}

.card-pill {
  font-size: 11px;
  padding: 3px 9px;
  border-radius: var(--radius-pill);
  background: rgba(5, 12, 9, 0.9);
  border: 1px solid rgba(255, 255, 255, 0.12);
  color: var(--accent-fruit);
}

.card-subtitle {
  font-size: 12px;
  color: var(--text-muted);
  margin-bottom: 10px;
}

/* Lesson text */

.lesson-text {
  font-size: 13px;
  line-height: 1.55;
  color: var(--text-main);
}

.lesson-highlight {
  color: var(--accent-fruit);
  font-weight: 500;
}

/* Quiz */

.quiz-question {
  font-size: 13px;
  margin-bottom: 8px;
  font-weight: 500;
}

.quiz-options {
  display: flex;
  flex-direction: column;
  gap: 6px;
  margin-bottom: 10px;
}

.quiz-option {
  border-radius: 999px;
  border: 1px solid var(--border-soft);
  background: rgba(8, 18, 13, 0.95);
  padding: 7px 11px;
  font-size: 12px;
  display: flex;
  align-items: center;
  gap: 8px;
  cursor: pointer;
  transition: border var(--transition-fast), background var(--transition-fast), transform var(--transition-fast);
}

.quiz-option input {
  accent-color: var(--accent-rose);
}

.quiz-option:hover {
  border-color: rgba(255, 255, 255, 0.25);
  transform: translateY(-1px);
}

.quiz-actions {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 8px;
}

.btn-primary {
  border: none;
  border-radius: var(--radius-pill);
  padding: 7px 16px;
  font-size: 12px;
  font-weight: 600;
  cursor: pointer;
  background: linear-gradient(135deg, var(--accent-rose), var(--accent-fruit));
  color: #050806;
  box-shadow: 0 10px 24px rgba(0, 0, 0, 0.45);
  transition: transform var(--transition-fast), box-shadow var(--transition-fast), filter var(--transition-fast);
}

.btn-primary:hover {
  transform: translateY(-1px);
  filter: brightness(1.05);
  box-shadow: 0 14px 30px rgba(0, 0, 0, 0.55);
}

.quiz-feedback {
  font-size: 12px;
  color: var(--text-muted);
}

/* Right column: progress / garden */

.progress-card {
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.progress-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 12px;
}

.progress-badge {
  padding: 3px 9px;
  border-radius: var(--radius-pill);
  border: 1px solid rgba(255, 255, 255, 0.16);
  background: rgba(5, 12, 9, 0.9);
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: 11px;
}

.progress-bar-outer {
  width: 100%;
  height: 7px;
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.06);
  overflow: hidden;
}

.progress-bar-inner {
  height: 100%;
  width: 32%;
  border-radius: inherit;
  background: linear-gradient(90deg, var(--accent-rose), var(--accent-fruit), var(--accent-leaf));
}

/* Little “garden” visual */

.garden-visual {
  margin-top: 6px;
  display: flex;
  gap: 8px;
  align-items: flex-end;
}

.garden-stem {
  flex: 1;
  height: 46px;
  border-radius: 999px;
  background: linear-gradient(180deg, rgba(76, 175, 80, 0.9), rgba(5, 12, 9, 0.9));
  position: relative;
  overflow: visible;
}

.garden-stem:nth-child(2) {
  height: 60px;
}

.garden-stem:nth-child(3) {
  height: 52px;
}

.garden-bloom {
  position: absolute;
  top: -14px;
  left: 50%;
  transform: translateX(-50%);
  width: 22px;
  height: 22px;
  border-radius: 999px;
  border: 1px solid rgba(255, 255, 255, 0.6);
  background:
    radial-gradient(circle at 30% 20%, #ff6b9c, transparent 60%),
    radial-gradient(circle at 70% 80%, #ffb347, transparent 60%);
}

/* Footer */

.app-footer {
  margin-top: 14px;
  font-size: 11px;
  color: var(--text-muted);
  display: flex;
  justify-content: space-between;
  gap: 8px;
  align-items: center;
}

.app-footer a {
  color: var(--accent-fruit);
  text-decoration: none;
  font-weight: 500;
  font-size: 11px;
}

.app-footer a:hover {
  text-decoration: underline;
}