*,
*::before,
*::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

:root {
  --blue: #094074;
  --blue-light: #1264b0;
  --text: #1a1a2e;
  --muted: #555;
  --bg-soft: #f5f8fc;
  --border: #dde4ef;
  --radius: 10px;
}

html {
  scroll-behavior: smooth;
}

body {
  font-family:
    system-ui,
    -apple-system,
    "Segoe UI",
    sans-serif;
  color: var(--text);
  background: #fff;
  line-height: 1.6;
}

a {
  color: inherit;
  text-decoration: none;
}

/* ── Layout helpers ── */
.container {
  max-width: 960px;
  margin: 0 auto;
  padding: 0 24px;
}

/* ── Header ── */
header {
  background: #fff;
  border-bottom: 1px solid var(--border);
  padding: 16px 0;
}

header .inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
}

header img {
  height: 40px;
}

header nav a.app-link {
  position: relative;
}

.tooltip {
  position: absolute;
  top: calc(100% + 8px);
  left: 50%;
  transform: translateX(-50%);
  background: var(--text);
  color: #fff;
  font-size: 0.75rem;
  font-weight: 500;
  white-space: nowrap;
  padding: 4px 10px;
  border-radius: 6px;
  pointer-events: none;
  opacity: 0;
  transition: opacity 0.15s;
}

.tooltip::after {
  content: "";
  position: absolute;
  bottom: 100%;
  left: 50%;
  transform: translateX(-50%);
  border: 5px solid transparent;
  border-bottom-color: var(--text);
}

header nav a.app-link:hover .tooltip {
  opacity: 1;
}

header nav a {
  color: var(--blue);
  font-size: 14px;
  font-weight: 600;
  padding: 6px 14px;
  border-radius: 6px;
  border: 1.5px solid var(--blue);
  transition:
    background 0.15s,
    color 0.15s;
}

header nav a:hover {
  background: var(--blue);
  color: #fff;
}

/* ── Hero ── */
.hero {
  background:
    linear-gradient(
      160deg,
      rgba(60, 105, 151, 0.93) 0%,
      rgba(90, 219, 255, 0.82) 100%
    ),
    url("preview-classroom.png") center / cover no-repeat;
  color: #fff;
  padding: 72px 0 80px;
}

.hero-inner {
  display: flex;
  align-items: center;
  gap: 48px;
}

.hero-text {
  flex: 1;
  min-width: 0;
}

.hero h1 {
  font-size: clamp(1.8rem, 4vw, 3rem);
  font-weight: 700;
  line-height: 1.2;
  margin-bottom: 20px;
  text-shadow: 0 1px 6px rgba(0, 0, 0, 0.25);
}

.hero p {
  font-size: 1.1rem;
  opacity: 0.92;
  margin-bottom: 36px;
}

.hero-visuals {
  flex: 1;
  position: relative;
  min-height: 260px;
  display: flex;
  align-items: flex-start;
  justify-content: flex-end;
}

.img-wrap {
  position: relative;
  display: block;
}

.img-wrap .ai-label {
  position: absolute;
  bottom: 4px;
  right: 6px;
  font-size: 0.65rem;
  color: rgba(255, 255, 255, 0.75);
  pointer-events: none;
  text-shadow: 0 1px 3px rgba(0, 0, 0, 0.5);
  letter-spacing: 0.02em;
}

.hero-card {
  border-radius: 12px;
  box-shadow: 0 10px 40px rgba(0, 0, 0, 0.35);
}

.hero-card-main {
  width: 75%;
  border: 3px solid rgba(255, 255, 255, 0.35);
  border-radius: 12px;
  overflow: hidden;
  margin-left: auto;
}

.hero-card-float {
  position: absolute;
  bottom: -28px;
  left: 0;
  width: 52%;
  border: 3px solid #fff;
  border-radius: 12px;
  overflow: hidden;
  box-shadow: 0 12px 40px rgba(0, 0, 0, 0.4);
}

.btn-primary {
  display: inline-block;
  background: #fff;
  color: var(--blue);
  font-weight: 700;
  font-size: 1rem;
  padding: 14px 32px;
  border-radius: var(--radius);
  transition:
    transform 0.15s,
    box-shadow 0.15s;
  box-shadow: 0 4px 16px rgba(0, 0, 0, 0.18);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 24px rgba(0, 0, 0, 0.22);
}

/* ── Features ── */
.features {
  padding: 72px 0;
}

.features-teachers {
  background: var(--bg-soft);
  border-top: 1px solid var(--border);
}

.section-header {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 14px;
  margin-bottom: 48px;
}

.section-label {
  display: inline-block;
  background: var(--blue);
  color: #fff;
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  padding: 4px 12px;
  border-radius: 20px;
  white-space: nowrap;
  flex-shrink: 0;
}

.features h2 {
  font-size: 1.75rem;
  font-weight: 700;
  margin: 0;
  color: var(--blue);
}

.feature-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 28px;
}

.feature-card {
  background: var(--bg-soft);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 28px 24px;
}

.feature-card .icon {
  font-size: 2rem;
  margin-bottom: 12px;
}

.feature-card h3 {
  font-size: 1.05rem;
  font-weight: 600;
  margin-bottom: 8px;
  color: var(--blue);
}

.feature-card p {
  font-size: 0.9rem;
  color: var(--muted);
  line-height: 1.55;
}

/* ── CTA Banner ── */
.cta-banner {
  background: var(--bg-soft);
  border-top: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
  padding: 64px 0;
  text-align: center;
}

.cta-banner h2 {
  font-size: 1.6rem;
  font-weight: 700;
  margin-bottom: 16px;
}

.cta-banner p {
  color: var(--muted);
  margin-bottom: 32px;
  max-width: 500px;
  margin-left: auto;
  margin-right: auto;
}

.btn-secondary {
  display: inline-block;
  background: var(--blue);
  color: #fff;
  font-weight: 700;
  font-size: 1rem;
  padding: 14px 32px;
  border-radius: var(--radius);
  transition:
    background 0.15s,
    transform 0.15s;
  box-shadow: 0 4px 16px rgba(9, 64, 116, 0.3);
}

.btn-secondary:hover {
  background: var(--blue-light);
  transform: translateY(-2px);
}

/* ── Legal pages ── */
.page-content {
  padding: 56px 0 72px;
  max-width: 720px;
  margin: 0 auto;
}

.page-content h1 {
  font-size: 1.75rem;
  font-weight: 700;
  color: var(--blue);
  margin-bottom: 40px;
}

.page-content h2 {
  font-size: 1.05rem;
  font-weight: 700;
  color: var(--text);
  margin: 28px 0 8px;
}

.page-content p,
.page-content li {
  font-size: 0.95rem;
  color: var(--muted);
  line-height: 1.7;
  margin-bottom: 6px;
}

.page-content ul {
  padding-left: 20px;
  margin-bottom: 8px;
}

.page-content .block {
  margin-bottom: 32px;
}

.page-content .sub-label {
  font-weight: 600;
  color: var(--text);
  margin: 12px 0 4px;
  font-size: 0.95rem;
}

/* ── Footer ── */
footer {
  padding: 28px 0;
  text-align: center;
  font-size: 0.85rem;
  color: var(--muted);
}

footer a {
  color: var(--blue);
}
footer a:hover {
  text-decoration: underline;
}

footer .links {
  display: flex;
  justify-content: center;
  gap: 20px;
  flex-wrap: wrap;
  margin-top: 8px;
}

@media (max-width: 640px) {
  .hero {
    padding: 48px 0 72px;
  }
  .hero-inner {
    flex-direction: column;
    gap: 32px;
  }
  .hero-card-main {
    width: 85%;
  }
  .hero-card-float {
    bottom: -24px;
    width: 50%;
  }
  .section-header {
    flex-direction: column;
    align-items: center;
    gap: 6px;
  }
  .feature-card {
    display: grid;
    grid-template-columns: auto 1fr;
    grid-template-rows: auto auto;
    column-gap: 10px;
    align-items: center;
  }
  .feature-card .icon {
    font-size: 1.3rem;
    margin-bottom: 0;
    grid-column: 1;
    grid-row: 1;
    line-height: 1;
    align-self: start;
    margin-top: 3px;
    display: flex;
    align-items: center;
  }
  .feature-card h3 {
    grid-column: 2;
    grid-row: 1;
    align-self: start;
  }
  .feature-card p {
    grid-column: 1 / -1;
    grid-row: 2;
    margin-top: 6px;
  }
}