@import url('https://fonts.googleapis.com/css2?family=Sora:wght@400;500;600;700&family=Lora:ital,wght@0,400;0,600;1,400&display=swap');

:root {
  --bg:        #0e0e12;
  --surface:   #15151c;
  --surface2:  #1c1c26;
  --border:    rgba(255,255,255,0.07);
  --border-hi: rgba(255,255,255,0.13);
  --text:      #dde1ea;
  --text-mid:  #8891a4;
  --text-dim:  #4a5162;
  --accent:    #4f8ef7;
  --accent-bg: rgba(79,142,247,0.1);
  --green:     #34d399;
  --green-bg:  rgba(52,211,153,0.1);
  --font-head: 'Lora', serif;
  --font-ui:   'Sora', sans-serif;
  --radius:    8px;
  --shadow:    0 2px 8px rgba(0,0,0,0.35);
  --shadow-md: 0 6px 20px rgba(0,0,0,0.45);
}

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

body {
  background: var(--bg);
  color: var(--text);
  font-family: var(--font-ui);
  font-size: 15px;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}

/* ── NAV ── */
nav {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(14,14,18,0.9);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--border);
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 2.5rem;
  height: 60px;
}

nav a:first-child {
  display: flex;
  align-items: center;
  height: 100%;
}

.nav-logo img,
img.nav-logo {
  height: 100%;
  max-height: 100%;
  width: auto;
  max-width: 150px;
  display: block;
  object-fit: contain;
}

/* Fallback text if no logo uploaded yet */
.nav-logo-fallback {
  font-family: var(--font-head);
  font-size: 1.15rem;
  color: var(--text);
  text-decoration: none;
  font-style: italic;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 0.25rem;
  list-style: none;
}

.nav-links a {
  font-size: 0.82rem;
  font-weight: 500;
  color: var(--text-mid);
  text-decoration: none;
  padding: 0.38rem 0.85rem;
  border-radius: var(--radius);
  border: 1px solid transparent;
  transition: color 0.15s, background 0.15s, border-color 0.15s;
}

.nav-links a:hover {
  color: var(--text);
  background: var(--surface);
  border-color: var(--border);
}

.nav-links a.active {
  color: var(--accent);
  background: var(--accent-bg);
  border-color: rgba(79,142,247,0.25);
}

/* ── HERO ── */
.hero {
  padding: 6rem 2.5rem 5rem;
  max-width: 900px;
  margin: 0 auto;
}

.hero-label {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 0.72rem;
  font-weight: 600;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 1.5rem;
}

.hero-label::before {
  content: '';
  display: block;
  width: 18px; height: 1px;
  background: var(--accent);
}

.hero-title {
  font-family: var(--font-head);
  font-size: clamp(2.4rem, 5vw, 3.8rem);
  line-height: 1.18;
  color: #fff;
  margin-bottom: 1.25rem;
  font-weight: 600;
  max-width: 640px;
}

.hero-sub {
  font-size: 0.97rem;
  color: var(--text-mid);
  max-width: 480px;
  line-height: 1.8;
}

/* ── PAGE INNER ── */
.page-inner {
  max-width: 900px;
  margin: 0 auto;
  padding: 0 2.5rem 6rem;
}

/* ── DIVIDER HEADING ── */
.section-heading {
  display: flex;
  align-items: center;
  gap: 1rem;
  margin-bottom: 1.5rem;
  margin-top: 3.5rem;
}

.section-heading h2 {
  font-family: var(--font-head);
  font-size: 1.3rem;
  font-weight: 600;
  color: #fff;
  white-space: nowrap;
}

.section-heading::after {
  content: '';
  flex: 1;
  height: 1px;
  background: var(--border);
}

.section-heading small {
  font-size: 0.75rem;
  color: var(--text-dim);
  white-space: nowrap;
}

/* ── ABOUT GRID ── */
.about-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1rem;
}

@media (max-width: 600px) { .about-grid { grid-template-columns: 1fr; } }

.about-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1.5rem;
}

.about-card h3 {
  font-size: 0.68rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--text-dim);
  margin-bottom: 0.65rem;
}

.about-card p {
  font-size: 0.88rem;
  color: var(--text-mid);
  line-height: 1.8;
}

.status-pill {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  font-size: 0.72rem;
  font-weight: 600;
  color: var(--green);
  background: var(--green-bg);
  padding: 0.2rem 0.65rem;
  border-radius: 99px;
  margin-top: 1rem;
}

.status-pill::before {
  content: '';
  width: 6px; height: 6px;
  border-radius: 50%;
  background: var(--green);
}

/* ── SUBJECT GRID ── */
.subjects-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
  gap: 1rem;
}

.subject-card {
  display: flex;
  flex-direction: column;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1.35rem;
  text-decoration: none;
  color: var(--text);
  box-shadow: var(--shadow);
  transition: border-color 0.15s, background 0.15s, box-shadow 0.15s;
}

.subject-card:hover {
  border-color: rgba(79,142,247,0.35);
  background: var(--surface2);
  box-shadow: var(--shadow-md);
}

.subject-card-num {
  font-size: 0.67rem;
  font-weight: 600;
  color: var(--text-dim);
  margin-bottom: 0.75rem;
  letter-spacing: 0.05em;
}

.subject-card-title {
  font-family: var(--font-head);
  font-size: 1.05rem;
  color: #fff;
  margin-bottom: 0.35rem;
  font-weight: 600;
}

.subject-card-desc {
  font-size: 0.78rem;
  color: var(--text-mid);
  line-height: 1.55;
  flex: 1;
}

.subject-card-link {
  font-size: 0.78rem;
  font-weight: 600;
  color: var(--accent);
  margin-top: 1.1rem;
}

/* ── SUBJECT PAGE HEADER ── */
.subject-header {
  border-bottom: 1px solid var(--border);
  padding: 4rem 2.5rem 2.5rem;
}

.subject-header-inner {
  max-width: 900px;
  margin: 0 auto;
}

.breadcrumb {
  font-size: 0.78rem;
  color: var(--text-dim);
  margin-bottom: 1.5rem;
  display: flex;
  align-items: center;
  gap: 0.4rem;
}

.breadcrumb a { color: var(--text-mid); text-decoration: none; }
.breadcrumb a:hover { color: var(--text); }
.breadcrumb .sep { color: var(--text-dim); }

.subject-num-tag {
  font-size: 0.67rem;
  font-weight: 600;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--text-dim);
  background: var(--surface2);
  border: 1px solid var(--border);
  padding: 0.2rem 0.6rem;
  border-radius: 4px;
  display: inline-block;
  margin-bottom: 1rem;
}

.subject-title {
  font-family: var(--font-head);
  font-size: clamp(1.9rem, 4vw, 2.8rem);
  color: #fff;
  margin-bottom: 0.75rem;
  font-weight: 600;
}

.subject-tagline {
  font-size: 0.93rem;
  color: var(--text-mid);
  max-width: 460px;
  line-height: 1.75;
}

/* ── SUBJECT BODY LAYOUT ── */
.subject-body {
  max-width: 900px;
  margin: 0 auto;
  padding: 2.5rem 2.5rem 6rem;
  display: grid;
  grid-template-columns: 1fr 230px;
  gap: 2rem;
  align-items: start;
}

@media (max-width: 720px) { .subject-body { grid-template-columns: 1fr; } }

.subject-main > * + * { margin-top: 1rem; }

/* ── CONTENT CARDS ── */
.content-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1.5rem;
}

.content-card h2 {
  font-size: 0.67rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--text-dim);
  margin-bottom: 0.75rem;
  padding-bottom: 0.6rem;
  border-bottom: 1px solid var(--border);
}

.content-card p {
  font-size: 0.88rem;
  color: var(--text-mid);
  line-height: 1.8;
}

.placeholder {
  margin-top: 0.9rem;
  background: var(--surface2);
  border: 1px dashed rgba(255,255,255,0.08);
  border-radius: var(--radius);
  padding: 1.5rem 1rem;
  text-align: center;
  font-size: 0.77rem;
  color: var(--text-dim);
}

/* ── SIDEBAR ── */
.subject-sidebar > * + * { margin-top: 1rem; }

.sidebar-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1.2rem;
}

.sidebar-card h3 {
  font-size: 0.67rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--text-dim);
  margin-bottom: 0.7rem;
  padding-bottom: 0.55rem;
  border-bottom: 1px solid var(--border);
}

.sidebar-nav-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 0.1rem;
}

.sidebar-nav-list a {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0.35rem 0.55rem;
  border-radius: 5px;
  font-size: 0.8rem;
  color: var(--text-mid);
  text-decoration: none;
  transition: background 0.12s, color 0.12s;
}

.sidebar-nav-list a:hover { background: var(--surface2); color: var(--text); }
.sidebar-nav-list a.current {
  background: var(--accent-bg);
  color: var(--accent);
  font-weight: 600;
}

.sidebar-nav-list a .num {
  font-size: 0.67rem;
  color: var(--text-dim);
}

/* ── PAGE NAV ── */
.page-nav-row {
  display: flex;
  justify-content: space-between;
  margin-top: 2rem;
  padding-top: 1.5rem;
  border-top: 1px solid var(--border);
}

.page-nav-btn {
  font-size: 0.8rem;
  font-weight: 600;
  color: var(--text-mid);
  text-decoration: none;
  padding: 0.45rem 1rem;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--surface);
  transition: color 0.15s, border-color 0.15s, background 0.15s;
}

.page-nav-btn:hover {
  color: var(--text);
  border-color: var(--border-hi);
  background: var(--surface2);
}

.page-nav-btn.ghost {
  opacity: 0.3;
  pointer-events: none;
}

/* ── FOOTER ── */
footer {
  border-top: 1px solid var(--border);
  padding: 1.25rem 2.5rem;
  display: flex;
  justify-content: space-between;
  font-size: 0.77rem;
  color: var(--text-dim);
}

footer a { color: var(--text-mid); text-decoration: none; }
footer a:hover { color: var(--text); }

/* ── VIDEO EMBED ── */
.vak-video {
  position: relative;
  width: 100%;
  padding-bottom: 56.25%;
  margin-bottom: 2rem;
  border-radius: var(--radius);
  overflow: hidden;
}

.vak-video iframe {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  border: none;
}