:root {
  --ink: #1b1c1e;
  --muted: #5b6570;
  --accent: #1d6b6b;
  --accent-soft: #d9efe9;
  --accent-warm: #e2a360;
  --bg-start: #f7f2ea;
  --bg-end: #e6eff7;
  --surface: #ffffff;
  --surface-shadow: 0 20px 60px rgba(20, 34, 52, 0.12);
  --radius-lg: 18px;
  --radius-md: 12px;
  --font-sans: "Fira Sans", "Segoe UI", "Helvetica Neue", sans-serif;
  --font-serif: "Fraunces", "Georgia", serif;
}

html {
  color-scheme: light;
  background-color: var(--bg-start);
}

body {
  font-family: var(--font-sans);
  color: var(--ink);
  background: linear-gradient(160deg, var(--bg-start), var(--bg-end));
  min-height: 100vh;
}

a {
  color: var(--accent);
}

a:hover {
  color: #144c4c;
}

.app-backdrop {
  position: fixed;
  inset: 0;
  background:
    radial-gradient(circle at 15% 20%, rgba(226, 163, 96, 0.22), transparent 55%),
    radial-gradient(circle at 85% 15%, rgba(29, 107, 107, 0.18), transparent 60%),
    radial-gradient(circle at 50% 80%, rgba(34, 72, 122, 0.12), transparent 60%);
  pointer-events: none;
  z-index: 0;
}

.app-hero {
  position: relative;
  z-index: 1;
}

.app-eyebrow {
  text-transform: uppercase;
  letter-spacing: 0.18em;
  font-size: 0.75rem;
  color: var(--muted);
  margin-bottom: 0.75rem;
}

.app-title {
  font-family: var(--font-serif);
  color: var(--ink);
}

.app-subtitle {
  color: var(--muted);
}

.hero-card {
  background: var(--surface);
  border-radius: var(--radius-lg);
  padding: 1rem;
  box-shadow: var(--surface-shadow);
}

.hero-card img {
  width: 100%;
  border-radius: var(--radius-md);
}

.app-main {
  position: relative;
  z-index: 1;
}

.app-tabs {
  margin-bottom: 1.5rem;
}

.app-tabs li.is-active a {
  background: var(--accent);
  border-color: var(--accent);
  color: #fff;
}

.app-box {
  border-radius: var(--radius-md);
  box-shadow: var(--surface-shadow);
  border: 1px solid rgba(29, 107, 107, 0.08);
}

.app-promo {
  border: 2px solid rgba(29, 107, 107, 0.25);
  background: linear-gradient(120deg, rgba(29, 107, 107, 0.12), rgba(226, 163, 96, 0.18));
}

.app-promo-eyebrow {
  text-transform: uppercase;
  letter-spacing: 0.18em;
  font-size: 0.7rem;
  color: var(--muted);
  margin-bottom: 0.5rem;
}

.app-promo .button {
  width: 100%;
  background: #fff;
  border: 2px solid var(--accent);
  color: var(--accent);
}

.app-promo .button:hover {
  background: var(--accent-soft);
  color: #0f3c3c;
}

.app-promo .title {
  margin-bottom: 0.4rem;
}

.app-promo-slim {
  border: 1px solid rgba(29, 107, 107, 0.2);
  background: #fff8f0;
}

.app-promo-slim .button {
  width: 100%;
  background: #fff;
  border: 1px solid var(--accent);
  color: var(--accent);
}

.app-promo-slim .button:hover {
  background: var(--accent-soft);
  color: #0f3c3c;
}

.app-summary .app-next-card {
  margin-top: 0.75rem;
}

.app-module {
  height: 100%;
}

.app-module.is-next {
  border-color: var(--accent);
  box-shadow: 0 18px 40px rgba(29, 107, 107, 0.18);
}

.app-module.is-complete {
  opacity: 0.9;
}

.app-module-header {
  display: flex;
  justify-content: space-between;
  gap: 1rem;
  align-items: flex-start;
}

.app-lesson-list {
  list-style: none;
  margin: 0.75rem 0 0;
  padding: 0;
}

.app-lesson-item {
  display: flex;
  justify-content: space-between;
  gap: 0.75rem;
  align-items: center;
  padding: 0.4rem 0.5rem;
  border-radius: 10px;
}

.app-lesson-item.is-complete a {
  color: var(--muted);
  text-decoration: line-through;
}

.app-lesson-item.is-next {
  background: rgba(29, 107, 107, 0.08);
}

.app-lesson-tag {
  flex-shrink: 0;
}

.app-list {
  margin-left: 1.2rem;
}

.app-list li.is-active > a {
  color: var(--accent);
  font-weight: 600;
}

.app-list li .app-tag-button {
  margin-left: 0.5rem;
}

.stack > * + * {
  margin-top: 0.75rem;
}

.view {
  display: none;
}

.view.is-active {
  display: block;
}


.lesson-card {
  border: 1px solid rgba(29, 107, 107, 0.15);
  border-radius: var(--radius-md);
  padding: 0.85rem;
  cursor: pointer;
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.lesson-card:hover {
  transform: translateY(-2px);
  box-shadow: 0 12px 30px rgba(29, 107, 107, 0.12);
}

.lesson-card.is-active {
  border-color: var(--accent);
  background: rgba(29, 107, 107, 0.08);
}

.app-tag-button {
  border: none;
  cursor: pointer;
  font-family: inherit;
}

.app-tag-button:hover {
  filter: brightness(0.95);
}

.app-tag-button:focus-visible {
  outline: 2px solid rgba(29, 107, 107, 0.5);
  outline-offset: 2px;
}

.module-card {
  border: 1px solid rgba(29, 107, 107, 0.15);
  border-radius: var(--radius-md);
  padding: 1rem;
  cursor: pointer;
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.module-card:hover {
  transform: translateY(-2px);
  box-shadow: 0 12px 30px rgba(29, 107, 107, 0.12);
}

.module-card.is-active {
  border-color: var(--accent);
  background: rgba(29, 107, 107, 0.08);
}

.progress-bar {
  height: 8px;
  background: rgba(29, 107, 107, 0.12);
  border-radius: 999px;
  overflow: hidden;
}

.progress-bar span {
  display: block;
  height: 100%;
  background: var(--accent);
}

.tag.is-accent {
  background: var(--accent-soft);
  color: var(--accent);
}

.keypoints {
  background: rgba(29, 107, 107, 0.06);
  border-radius: var(--radius-md);
  padding: 1rem;
}

.markdown p + p {
  margin-top: 0.75rem;
}

.markdown ul,
.markdown ol {
  margin-left: 1.5rem;
  padding-left: 0.4rem;
  list-style-position: outside;
  margin-top: 0.6rem;
  margin-bottom: 0.6rem;
}

.markdown ul {
  list-style-type: disc;
}

.markdown ol {
  list-style-type: decimal;
}

.markdown li + li {
  margin-top: 0.35rem;
}

.markdown p + ul,
.markdown p + ol {
  margin-top: 0.6rem;
}

.markdown ul + p,
.markdown ol + p {
  margin-top: 0.6rem;
}

@media (max-width: 768px) {
  .hero-card {
    margin-top: 1rem;
  }

  .app-tabs ul {
    flex-wrap: wrap;
  }

  .app-promo .column {
    text-align: left;
  }
}