/* ============================================================
   SheLeads AI — Course Hub stylesheet
   Shares the dark theme + palette of the LLM explainer.
   ============================================================ */

:root {
  --bg: #0a0a0f;
  --bg-elev: #13131c;
  --bg-elev-2: #181826;
  --text: #f5f6fa;
  --text-dim: #a0a3b1;
  --text-faint: #5c5f70;
  --accent: #7c8cff; /* periwinkle */
  --accent-2: #4fd1c5; /* teal */
  --accent-3: #f7a8c4; /* soft pink — accent variety */
  --accent-4: #ffd166; /* warm amber — accent variety */
  --border: rgba(255, 255, 255, 0.08);
  --border-bright: rgba(255, 255, 255, 0.16);
  --max-width: 1180px;
  --font: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica,
    Arial, sans-serif;
  --mono: "SF Mono", "Fira Code", "Cascadia Code", Consolas, monospace;
}

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

html {
  scroll-behavior: smooth;
  scroll-padding-top: 80px;
}

body {
  background: var(--bg);
  color: var(--text);
  font-family: var(--font);
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

::selection {
  background: color-mix(in srgb, var(--accent) 40%, transparent);
}

::-webkit-scrollbar {
  width: 8px;
}
::-webkit-scrollbar-track {
  background: var(--bg);
}
::-webkit-scrollbar-thumb {
  background: var(--border-bright);
  border-radius: 4px;
}

a {
  color: var(--accent);
  text-decoration: none;
}

/* ---------- Progress bar ---------- */
.progress-bar {
  position: fixed;
  top: 0;
  left: 0;
  height: 3px;
  width: 0;
  background: linear-gradient(90deg, var(--accent), var(--accent-2));
  z-index: 100;
  transition: width 0.1s linear;
}

/* ---------- Top bar ---------- */
.topbar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: 64px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 18px;
  padding: 0 clamp(16px, 4vw, 32px);
  background: rgba(10, 10, 15, 0.72);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
  z-index: 95;
}

.topbar-brand {
  display: flex;
  align-items: center;
  gap: 10px;
  color: var(--text);
}

.brand-mark {
  width: 30px;
  height: 30px;
  border-radius: 9px;
  background: linear-gradient(135deg, var(--accent), var(--accent-2));
  display: grid;
  place-items: center;
  font-weight: 800;
  font-size: 0.95rem;
  color: #0a0a0f;
  letter-spacing: -0.03em;
  flex-shrink: 0;
}

.topbar-title {
  font-weight: 700;
  letter-spacing: -0.01em;
}
.topbar-title span {
  color: var(--accent-2);
}

.topbar-links {
  display: flex;
  align-items: center;
  gap: 22px;
  font-size: 0.9rem;
}
.topbar-links a {
  color: var(--text-dim);
  transition: color 0.2s;
}
.topbar-links a:hover {
  color: var(--text);
}

@media (max-width: 640px) {
  .topbar-links {
    display: none;
  }
}

/* ---------- Hero ---------- */
.hero {
  min-height: 86vh;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: 96px 24px 64px;
  position: relative;
  background: radial-gradient(
      ellipse at 50% 0%,
      rgba(124, 140, 255, 0.16),
      transparent 55%
    ),
    radial-gradient(ellipse at 80% 90%, rgba(79, 209, 197, 0.1), transparent 50%);
}

.eyebrow {
  text-transform: uppercase;
  letter-spacing: 0.25em;
  font-size: 0.78rem;
  color: var(--accent-2);
  margin-bottom: 1.4rem;
}

.hero h1 {
  font-size: clamp(2.4rem, 7vw, 5rem);
  font-weight: 800;
  line-height: 1.05;
  letter-spacing: -0.03em;
  max-width: 16ch;
  background: linear-gradient(180deg, #ffffff, #b9bdd6);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
}
.hero h1 .grad {
  background: linear-gradient(120deg, var(--accent), var(--accent-2));
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
}

.hero-by {
  margin-top: 1.1rem;
  display: inline-block;
  font-size: clamp(0.8rem, 1.8vw, 0.95rem);
  font-weight: 700;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--accent-2);
  padding: 6px 16px;
  border: 1px solid color-mix(in srgb, var(--accent-2) 45%, var(--border));
  border-radius: 999px;
  background: color-mix(in srgb, var(--accent-2) 10%, transparent);
}

.hero-tagline {
  margin-top: 1.6rem;
  font-size: clamp(1rem, 2.2vw, 1.2rem);
  color: var(--text-dim);
  max-width: 56ch;
}

.hero-cta {
  margin-top: 2.4rem;
  display: flex;
  gap: 14px;
  flex-wrap: wrap;
  justify-content: center;
}

.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 12px 24px;
  border-radius: 12px;
  font-weight: 600;
  font-size: 0.95rem;
  border: 1px solid var(--border-bright);
  color: var(--text);
  background: var(--bg-elev);
  cursor: pointer;
  transition: transform 0.2s, border-color 0.2s, background 0.2s;
}
.btn:hover {
  transform: translateY(-2px);
  border-color: var(--accent);
}
.btn.primary {
  background: linear-gradient(135deg, var(--accent), var(--accent-2));
  color: #0a0a0f;
  border-color: transparent;
}
.btn.primary:hover {
  filter: brightness(1.08);
}

/* ---------- Stats strip ---------- */
.stats {
  display: flex;
  justify-content: center;
  gap: clamp(24px, 6vw, 72px);
  flex-wrap: wrap;
  padding: 36px 24px;
  border-top: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
  background: var(--bg-elev);
}
.stat {
  text-align: center;
}
.stat-num {
  font-size: clamp(1.8rem, 4vw, 2.6rem);
  font-weight: 800;
  letter-spacing: -0.02em;
  line-height: 1;
}
.stat-num.a {
  color: var(--accent);
}
.stat-num.b {
  color: var(--accent-2);
}
.stat-num.c {
  color: var(--accent-3);
}
.stat-num.d {
  color: var(--accent-4);
}
.stat-lbl {
  margin-top: 8px;
  font-size: 0.74rem;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  color: var(--text-faint);
}

/* ---------- Curriculum section ---------- */
.curriculum {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: clamp(56px, 9vw, 96px) clamp(20px, 5vw, 32px) 96px;
}

.section-head {
  text-align: center;
  margin-bottom: 56px;
}
.section-head .eyebrow {
  display: block;
  margin-bottom: 0.8rem;
}
.section-head h2 {
  font-size: clamp(1.8rem, 4.5vw, 2.8rem);
  font-weight: 800;
  letter-spacing: -0.02em;
}
.section-head p {
  margin-top: 0.9rem;
  color: var(--text-dim);
  max-width: 56ch;
  margin-left: auto;
  margin-right: auto;
}

/* ---------- Session cards grid ---------- */
.sessions {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(330px, 1fr));
  gap: 22px;
}

.card {
  position: relative;
  display: flex;
  flex-direction: column;
  background: var(--bg-elev);
  border: 1px solid var(--border);
  border-radius: 18px;
  padding: 26px 24px 24px;
  overflow: hidden;
  opacity: 0;
  transform: translateY(26px);
  transition: opacity 0.6s ease, transform 0.6s ease, border-color 0.25s,
    background 0.25s;
}
.card.visible {
  opacity: 1;
  transform: translateY(0);
}

/* accent glow line on top */
.card::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: var(--card-accent, var(--accent));
  opacity: 0.85;
}

.card.ready:hover {
  border-color: color-mix(in srgb, var(--card-accent) 50%, var(--border));
  background: var(--bg-elev-2);
  transform: translateY(-4px);
}

.card.soon {
  opacity: 0.62;
}
.card.soon.visible {
  opacity: 0.62;
}

.card-top {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 18px;
}

.card-badge {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  padding: 5px 12px;
  border-radius: 999px;
  color: var(--card-accent, var(--accent));
  background: color-mix(in srgb, var(--card-accent) 12%, transparent);
  border: 1px solid color-mix(in srgb, var(--card-accent) 30%, var(--border));
}

.card-status {
  font-size: 0.7rem;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--text-faint);
  display: inline-flex;
  align-items: center;
  gap: 6px;
}
.card-status .dot {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--text-faint);
}
.card-status.live {
  color: var(--accent-2);
}
.card-status.live .dot {
  background: var(--accent-2);
  box-shadow: 0 0 8px var(--accent-2);
}

.card h3 {
  font-size: 1.25rem;
  font-weight: 700;
  letter-spacing: -0.01em;
  line-height: 1.25;
}
.card .card-sub {
  margin-top: 8px;
  color: var(--text-dim);
  font-size: 0.92rem;
}

.topic-chips {
  display: flex;
  flex-wrap: wrap;
  gap: 7px;
  margin-top: 18px;
}
.chip {
  font-size: 0.74rem;
  color: var(--text-dim);
  padding: 4px 10px;
  border-radius: 8px;
  background: rgba(255, 255, 255, 0.04);
  border: 1px solid var(--border);
}

.card-links {
  margin-top: auto;
  padding-top: 22px;
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}
.card-link {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  font-size: 0.86rem;
  font-weight: 600;
  padding: 9px 15px;
  border-radius: 10px;
  color: var(--text);
  background: color-mix(in srgb, var(--card-accent) 14%, transparent);
  border: 1px solid color-mix(in srgb, var(--card-accent) 32%, var(--border));
  transition: transform 0.18s, background 0.2s;
}
.card-link:hover {
  transform: translateX(3px);
  background: color-mix(in srgb, var(--card-accent) 24%, transparent);
}
.card-link .arrow {
  transition: transform 0.18s;
}
.card-link:hover .arrow {
  transform: translateX(3px);
}

.card-soon-note {
  margin-top: auto;
  padding-top: 22px;
  font-size: 0.84rem;
  color: var(--text-faint);
  font-style: italic;
}

/* ---------- Footer ---------- */
.site-footer {
  border-top: 1px solid var(--border);
  background: var(--bg-elev);
  padding: 40px 24px 48px;
  text-align: center;
}
.site-footer p {
  color: var(--text-faint);
  font-size: 0.85rem;
}
.site-footer .footer-brand {
  font-weight: 700;
  color: var(--text-dim);
  margin-bottom: 6px;
}
.site-footer a {
  color: var(--accent-2);
}

/* ---------- Reveal-on-scroll helper ---------- */
.reveal {
  opacity: 0;
  transform: translateY(22px);
  transition: opacity 0.7s ease, transform 0.7s ease;
}
.reveal.visible {
  opacity: 1;
  transform: translateY(0);
}