/* ===== BCA Sathi — gold/white/navy theme ===== */
:root {
  --bg: #ffffff;
  --bg-soft: #FFFDF6;
  --text: #1A2B4C;
  --text-muted: #5A6B85;
  --gold: #C9A227;
  --gold-soft: #F5E9C2;
  --blue: #1E5AA8;
  --blue-dark: #164078;
  --border: #E8E4D6;
  --radius: 10px;
  --shadow: 0 2px 8px rgba(26, 43, 76, 0.06);
  --shadow-hover: 0 6px 20px rgba(26, 43, 76, 0.12);
}

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

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  color: var(--text);
  background: var(--bg);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

a { color: var(--blue); text-decoration: none; }
a:hover { text-decoration: underline; }

.container {
  max-width: 1100px;
  margin: 0 auto;
  padding: 0 20px;
}

/* ===== Header ===== */
.site-header {
  background: #fff;
  border-bottom: 1px solid var(--border);
  position: sticky;
  top: 0;
  z-index: 100;
}
.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
}
.logo {
  font-size: 1.35rem;
  font-weight: 700;
  color: var(--text);
}
.logo span { color: var(--gold); }

.nav {
  display: flex;
  align-items: center;
  gap: 24px;
}
.nav > a, .dropbtn {
  color: var(--text);
  font-size: 0.95rem;
  font-weight: 500;
  background: none;
  border: none;
  cursor: pointer;
  padding: 8px 0;
  font-family: inherit;
}
.nav > a:hover, .dropbtn:hover {
  color: var(--blue);
  text-decoration: none;
}

/* Dropdown */
.dropdown { position: relative; }
.dropdown-content {
  display: none;
  position: absolute;
  top: 100%;
  right: 0;
  background: #fff;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow-hover);
  min-width: 180px;
  padding: 6px 0;
}
.dropdown:hover .dropdown-content { display: block; }
.dropdown-content a {
  display: block;
  padding: 8px 16px;
  color: var(--text);
  font-size: 0.9rem;
}
.dropdown-content a:hover {
  background: var(--gold-soft);
  text-decoration: none;
}

/* ===== Hero ===== */
.hero {
  background: linear-gradient(180deg, var(--bg-soft) 0%, #fff 100%);
  padding: 64px 0 56px;
  text-align: center;
  border-bottom: 1px solid var(--border);
}
.hero h1 {
  font-size: clamp(1.8rem, 4vw, 2.6rem);
  font-weight: 800;
  letter-spacing: -0.02em;
  margin-bottom: 12px;
}
.hero .subhead {
  color: var(--text-muted);
  font-size: 1.05rem;
  margin-bottom: 28px;
  max-width: 620px;
  margin-left: auto;
  margin-right: auto;
}

/* ===== Buttons ===== */
.btn {
  display: inline-block;
  padding: 12px 22px;
  border-radius: var(--radius);
  font-weight: 600;
  font-size: 0.95rem;
  cursor: pointer;
  border: none;
  transition: all 0.15s ease;
  text-decoration: none;
}
.btn-primary {
  background: var(--blue);
  color: #fff;
}
.btn-primary:hover {
  background: var(--blue-dark);
  text-decoration: none;
  transform: translateY(-1px);
}
.btn-sm {
  padding: 7px 14px;
  font-size: 0.85rem;
  background: var(--blue);
  color: #fff;
}
.btn-sm:hover { background: var(--blue-dark); text-decoration: none; }

/* ===== Sections ===== */
.section { padding: 56px 0; }
.section h2 {
  font-size: 1.5rem;
  font-weight: 700;
  margin-bottom: 24px;
  text-align: center;
}

/* ===== Semester grid (home) ===== */
.grid-semesters {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
  gap: 18px;
}
.sem-card {
  display: flex;
  align-items: center;
  gap: 16px;
  padding: 22px;
  background: #fff;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  color: var(--text);
  transition: all 0.18s ease;
  border-top: 3px solid transparent;
}
.sem-card:hover {
  box-shadow: var(--shadow-hover);
  transform: translateY(-3px);
  border-top-color: var(--gold);
  text-decoration: none;
}
.sem-number {
  font-size: 2rem;
  font-weight: 800;
  color: var(--gold);
  line-height: 1;
  min-width: 40px;
}
.sem-info h3 { font-size: 1.05rem; font-weight: 700; margin-bottom: 2px; }
.sem-info p { font-size: 0.85rem; color: var(--text-muted); margin-bottom: 4px; }
.sem-count { font-size: 0.78rem; color: var(--blue); font-weight: 600; }

/* ===== Trust strip ===== */
.trust-strip { background: var(--bg-soft); border-top: 1px solid var(--border); border-bottom: 1px solid var(--border); }
.trust-row {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 24px;
  text-align: center;
}
.trust-item { font-size: 1.6rem; line-height: 1.3; }
.trust-item strong { display: block; font-size: 1rem; margin-top: 6px; color: var(--text); }
.trust-item span { display: block; font-size: 0.85rem; color: var(--text-muted); font-weight: 400; }

/* ===== Breadcrumb ===== */
.breadcrumb {
  font-size: 0.85rem;
  color: var(--text-muted);
  margin: 28px 0 12px;
}
.breadcrumb a { color: var(--blue); }
.breadcrumb span { color: var(--text); font-weight: 500; }

/* ===== Semester page ===== */
main.container h1 { font-size: 1.7rem; font-weight: 800; margin-bottom: 20px; }

.grid-subjects {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: 18px;
  margin-bottom: 60px;
}
.subject-card {
  background: #fff;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 20px;
  box-shadow: var(--shadow);
}
.subj-head { display: flex; justify-content: space-between; align-items: start; gap: 10px; margin-bottom: 14px; }
.subj-head h3 { font-size: 1.05rem; font-weight: 700; }
.subj-code {
  font-size: 0.72rem;
  font-weight: 600;
  background: var(--gold-soft);
  color: #7a6118;
  padding: 3px 8px;
  border-radius: 999px;
  white-space: nowrap;
}
.subj-links { display: flex; flex-wrap: wrap; gap: 8px; }
.chip {
  font-size: 0.82rem;
  padding: 6px 12px;
  border-radius: 999px;
  border: 1px solid var(--border);
  color: var(--text);
  background: #fff;
  font-weight: 500;
}
.chip:hover { border-color: var(--gold); background: var(--gold-soft); text-decoration: none; }
.chip-papers { border-color: #cfe0f5; background: #f2f7fd; }
.chip-notes { border-color: #e4d9b5; background: #fbf7ea; }

/* ===== Subject page ===== */
.tabs {
  display: flex;
  gap: 4px;
  border-bottom: 2px solid var(--border);
  margin: 24px 0 20px;
  overflow-x: auto;
}
.tab {
  background: none;
  border: none;
  padding: 12px 18px;
  font-family: inherit;
  font-size: 0.92rem;
  font-weight: 600;
  color: var(--text-muted);
  cursor: pointer;
  border-bottom: 2px solid transparent;
  margin-bottom: -2px;
  white-space: nowrap;
}
.tab:hover { color: var(--text); }
.tab.active { color: var(--text); border-bottom-color: var(--gold); }

.tab-content { margin-bottom: 60px; }
.resource-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 16px 18px;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  margin-bottom: 10px;
  background: #fff;
  gap: 12px;
  flex-wrap: wrap;
}
.row-actions { display: flex; align-items: center; gap: 14px; }

.muted { color: var(--text-muted); font-size: 0.88rem; }
.empty {
  padding: 32px;
  text-align: center;
  color: var(--text-muted);
  background: var(--bg-soft);
  border: 1px dashed var(--border);
  border-radius: var(--radius);
}

/* ===== Footer ===== */
.site-footer {
  background: var(--bg-soft);
  border-top: 1px solid var(--border);
  padding: 32px 0;
  text-align: center;
  font-size: 0.85rem;
  color: var(--text-muted);
  margin-top: 40px;
}
.site-footer p { margin: 4px 0; }

/* ===== Responsive ===== */
@media (max-width: 640px) {
  .nav { gap: 14px; }
  .logo { font-size: 1.15rem; }
  .hero { padding: 44px 0 40px; }
  .section { padding: 40px 0; }
  .grid-semesters { grid-template-columns: repeat(auto-fill, minmax(160px, 1fr)); }
  .sem-card { padding: 16px; flex-direction: column; align-items: flex-start; gap: 8px; }
  .resource-row { flex-direction: column; align-items: flex-start; }
}