/* ===== AIM Publication — stylesheet ===== */

:root {
  --navy: #0d2c6b;
  --navy-dark: #081d49;
  --blue: #1451c9;
  --orange: #ff8a00;
  --yellow: #ffc72c;
  --red: #e63946;
  --ink: #1a2233;
  --ink-soft: #5b6478;
  --bg: #f6f7fb;
  --card-bg: #ffffff;
  --border: #e7e9f2;
  --radius: 14px;
  --shadow: 0 6px 20px rgba(13, 44, 107, 0.08);
  --shadow-hover: 0 14px 32px rgba(13, 44, 107, 0.16);
  --max-width: 1240px;
  font-size: 16px;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  font-family: "Hind Siliguri", "Poppins", sans-serif;
  color: var(--ink);
  background: var(--bg);
  -webkit-font-smoothing: antialiased;
}

h1, h2, h3, h4 { font-family: "Hind Siliguri", sans-serif; margin: 0; }

a { text-decoration: none; color: inherit; }
ul { margin: 0; padding: 0; list-style: none; }
img { display: block; max-width: 100%; }

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  padding: 10px 20px;
  border-radius: 999px;
  font-weight: 600;
  font-size: 0.95rem;
  border: 2px solid transparent;
  cursor: pointer;
  transition: transform 0.15s ease, box-shadow 0.15s ease, background 0.15s ease;
  white-space: nowrap;
}
.btn:active { transform: scale(0.97); }

.btn-primary {
  background: linear-gradient(135deg, var(--orange), var(--yellow));
  color: var(--navy-dark);
  box-shadow: 0 6px 16px rgba(255, 138, 0, 0.35);
}
.btn-primary:hover { box-shadow: 0 10px 22px rgba(255, 138, 0, 0.45); }

.btn-outline {
  border-color: var(--navy);
  color: var(--navy);
  background: transparent;
}
.btn-outline:hover { background: var(--navy); color: #fff; }

.btn-block { width: 100%; }

/* ===== Header ===== */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: #fff;
  border-bottom: 1px solid var(--border);
}

.header-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 12px 20px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
}

.logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-weight: 700;
  font-size: 1.15rem;
  color: var(--navy-dark);
  flex-shrink: 0;
}

.logo-mark {
  width: 38px;
  height: 38px;
  border-radius: 10px;
  background: linear-gradient(135deg, var(--blue), var(--navy));
  color: #fff;
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: "Poppins", sans-serif;
  font-weight: 800;
  font-size: 1.2rem;
}

.logo-text em {
  font-style: normal;
  color: var(--orange);
}

.main-nav {
  display: flex;
  gap: 28px;
  font-weight: 600;
  color: var(--ink-soft);
}

.main-nav a:hover,
.main-nav a.active {
  color: var(--navy);
}

.header-actions {
  display: flex;
  align-items: center;
  gap: 14px;
}

.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 6px;
}
.nav-toggle span {
  width: 24px;
  height: 2.5px;
  background: var(--navy);
  border-radius: 2px;
}

/* ===== Hero / banner ===== */
.hero {
  background: var(--navy-dark);
  line-height: 0;
}
.hero-banner {
  width: 100%;
  height: auto;
  margin: 0 auto;
}

/* ===== Class jump nav ===== */
.class-jump {
  position: sticky;
  top: var(--header-h, 63px);
  z-index: 80;
  background: rgba(255, 255, 255, 0.92);
  backdrop-filter: saturate(180%) blur(8px);
  -webkit-backdrop-filter: saturate(180%) blur(8px);
  border-bottom: 1px solid var(--border);
  box-shadow: 0 4px 14px rgba(13, 44, 107, 0.05);
}

.class-jump-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 12px 20px;
  display: flex;
  align-items: center;
  gap: 16px;
  overflow-x: auto;
  scrollbar-width: none;
  -ms-overflow-style: none;
}
.class-jump-inner::-webkit-scrollbar { display: none; }

.class-jump-label {
  flex-shrink: 0;
  font-weight: 700;
  color: var(--navy-dark);
  font-size: 0.85rem;
  position: relative;
  padding-right: 14px;
}
.class-jump-label::after {
  content: "";
  position: absolute;
  right: 0;
  top: 50%;
  transform: translateY(-50%);
  width: 1px;
  height: 20px;
  background: var(--border);
}

.class-jump-links {
  display: flex;
  gap: 8px;
  flex-shrink: 0;
}

.class-jump-links a {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 6px 16px 6px 6px;
  border-radius: 999px;
  background: var(--bg);
  border: 1px solid var(--border);
  font-size: 0.86rem;
  font-weight: 600;
  color: var(--ink-soft);
  white-space: nowrap;
  flex-shrink: 0;
  scroll-snap-align: start;
  transition: background 0.18s ease, color 0.18s ease, border-color 0.18s ease, box-shadow 0.18s ease, transform 0.18s ease;
}

.class-jump-links a .num {
  width: 22px;
  height: 22px;
  border-radius: 50%;
  background: #fff;
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: "Poppins", sans-serif;
  font-weight: 700;
  font-size: 0.75rem;
  color: var(--navy);
  flex-shrink: 0;
  box-shadow: 0 1px 3px rgba(13, 44, 107, 0.15);
  transition: background 0.18s ease, color 0.18s ease;
}

.class-jump-links a:hover {
  border-color: var(--blue);
  color: var(--navy);
  transform: translateY(-1px);
}

.class-jump-links a.active {
  background: linear-gradient(135deg, var(--navy), var(--blue));
  border-color: transparent;
  color: #fff;
  box-shadow: 0 8px 18px rgba(13, 44, 107, 0.3);
}
.class-jump-links a.active .num {
  background: rgba(255, 255, 255, 0.22);
  color: #fff;
  box-shadow: none;
}

/* ===== Section shell ===== */
.section-head {
  text-align: center;
  max-width: 640px;
  margin: 0 auto 8px;
}
.section-head h2 {
  font-size: 1.7rem;
  color: var(--navy-dark);
}
.section-head p {
  color: var(--ink-soft);
  margin-top: 6px;
  font-size: 0.95rem;
}

.classes {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 40px 20px 10px;
}

/* ===== Class row ===== */
.class-section {
  margin-top: 40px;
  scroll-margin-top: var(--scroll-offset, 130px);
}

.class-section-head {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 12px;
  margin-bottom: 16px;
  padding-bottom: 10px;
  border-bottom: 2px solid var(--border);
}

.class-section-head h3 {
  font-size: 1.25rem;
  color: var(--navy-dark);
  display: flex;
  align-items: center;
  gap: 10px;
}

.class-pill {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 30px;
  height: 30px;
  padding: 0 8px;
  border-radius: 8px;
  background: var(--navy);
  color: #fff;
  font-family: "Poppins", sans-serif;
  font-weight: 700;
  font-size: 0.85rem;
}

.class-count {
  color: var(--ink-soft);
  font-size: 0.85rem;
  font-weight: 500;
}

.book-row {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(190px, 1fr));
  gap: 20px;
}

/* ===== Book card ===== */
.book-card {
  width: 100%;
  background: var(--card-bg);
  border-radius: var(--radius);
  border: 1px solid var(--border);
  overflow: hidden;
  cursor: pointer;
  transition: transform 0.2s ease, box-shadow 0.2s ease, border-color 0.2s ease;
  display: flex;
  flex-direction: column;
}

.book-card:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-hover);
  border-color: transparent;
}

.book-card:focus-visible {
  outline: 3px solid var(--blue);
  outline-offset: 2px;
}

.book-cover {
  position: relative;
  aspect-ratio: 3 / 4;
  overflow: hidden;
  background: var(--border);
}
.book-cover img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.3s ease;
}
.book-card:hover .book-cover img {
  transform: scale(1.05);
}

.book-badge {
  position: absolute;
  top: 8px;
  left: 8px;
  background: var(--blue);
  color: #fff;
  font-size: 0.68rem;
  font-weight: 700;
  padding: 3px 9px;
  border-radius: 999px;
  letter-spacing: 0.02em;
}

.book-info {
  padding: 12px 14px 14px;
  display: flex;
  flex-direction: column;
  gap: 6px;
  flex: 1;
}

.book-title {
  font-size: 0.92rem;
  font-weight: 700;
  color: var(--ink);
  line-height: 1.35;
}

.book-subjects {
  font-size: 0.78rem;
  color: var(--ink-soft);
  line-height: 1.4;
  flex: 1;
}

.book-footer {
  display: flex;
  align-items: center;
  margin-top: 6px;
  padding-top: 10px;
  border-top: 1px solid var(--border);
}

.book-view {
  font-size: 0.82rem;
  font-weight: 700;
  color: var(--blue);
  transition: transform 0.15s ease;
}

.book-card:hover .book-view {
  transform: translateX(3px);
}

/* ===== Why us ===== */
.why-us {
  max-width: var(--max-width);
  margin: 60px auto 0;
  padding: 0 20px;
}
.why-grid {
  margin-top: 26px;
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 18px;
}
.why-card {
  background: #fff;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 22px 18px;
  text-align: center;
}
.why-icon {
  font-size: 1.8rem;
  margin-bottom: 10px;
}
.why-card h3 {
  font-size: 1rem;
  color: var(--navy-dark);
  margin-bottom: 6px;
}
.why-card p {
  font-size: 0.85rem;
  color: var(--ink-soft);
  line-height: 1.5;
  margin: 0;
}

/* ===== About ===== */
.about {
  max-width: 780px;
  margin: 60px auto 0;
  padding: 0 20px;
  text-align: center;
}
.about-text {
  margin-top: 18px;
  color: var(--ink-soft);
  line-height: 1.8;
  font-size: 0.98rem;
}

/* ===== Footer ===== */
.site-footer {
  margin-top: 70px;
  background: var(--navy-dark);
  color: #cdd6ee;
}
.footer-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 44px 20px 24px;
  display: grid;
  grid-template-columns: 2fr 1fr 1.3fr;
  gap: 30px;
}
.footer-logo { color: #fff; margin-bottom: 10px; }
.footer-logo .logo-mark { background: linear-gradient(135deg, var(--orange), var(--yellow)); color: var(--navy-dark); }
.footer-col p { line-height: 1.7; font-size: 0.9rem; color: #a9b4d6; }
.footer-col h4 {
  color: #fff;
  font-size: 0.95rem;
  margin-bottom: 14px;
}
.footer-col a {
  display: block;
  padding: 5px 0;
  font-size: 0.9rem;
  color: #a9b4d6;
}
.footer-col a:hover { color: #fff; }

.footer-bottom {
  border-top: 1px solid rgba(255,255,255,0.1);
  text-align: center;
  padding: 16px 20px;
  font-size: 0.82rem;
  color: #8a95bd;
}

/* ===== WhatsApp float ===== */
.whatsapp-float {
  position: fixed;
  right: 20px;
  bottom: 20px;
  width: 56px;
  height: 56px;
  border-radius: 50%;
  background: #25d366;
  color: #fff;
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: 0 8px 20px rgba(37, 211, 102, 0.45);
  z-index: 90;
  transition: transform 0.15s ease;
}
.whatsapp-float:hover { transform: scale(1.08); }

/* ===== Modal ===== */
.modal-overlay {
  position: fixed;
  inset: 0;
  background: rgba(8, 15, 40, 0.55);
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 20px;
  z-index: 200;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.2s ease;
}
.modal-overlay.open {
  opacity: 1;
  pointer-events: auto;
}

.modal {
  background: #fff;
  border-radius: 18px;
  max-width: 800px;
  width: 100%;
  max-height: 88vh;
  overflow-y: auto;
  position: relative;
  transform: translateY(16px) scale(0.98);
  transition: transform 0.2s ease;
}
.modal-overlay.open .modal {
  transform: translateY(0) scale(1);
}

.modal-close {
  position: absolute;
  top: 14px;
  right: 14px;
  width: 36px;
  height: 36px;
  border-radius: 50%;
  border: none;
  background: var(--bg);
  color: var(--ink);
  font-size: 1.4rem;
  line-height: 1;
  cursor: pointer;
  z-index: 2;
}
.modal-close:hover { background: var(--border); }

.modal-body {
  display: grid;
  grid-template-columns: 260px 1fr;
  gap: 28px;
  padding: 28px;
}

.modal-gallery img {
  width: 100%;
  border-radius: 12px;
  border: 1px solid var(--border);
}
.modal-gallery .modal-wrap-toggle {
  display: flex;
  gap: 8px;
  margin-top: 10px;
}
.modal-gallery .modal-wrap-toggle button {
  flex: 1;
  padding: 7px 0;
  border-radius: 8px;
  border: 1px solid var(--border);
  background: #fff;
  font-size: 0.78rem;
  font-weight: 600;
  color: var(--ink-soft);
  cursor: pointer;
}
.modal-gallery .modal-wrap-toggle button.active {
  background: var(--navy);
  color: #fff;
  border-color: var(--navy);
}

.modal-details .modal-class-tag {
  display: inline-block;
  background: var(--yellow);
  color: var(--navy-dark);
  font-weight: 700;
  font-size: 0.78rem;
  padding: 4px 12px;
  border-radius: 999px;
  margin-bottom: 10px;
}

.modal-details h2 {
  font-size: 1.4rem;
  color: var(--navy-dark);
  line-height: 1.35;
  margin-bottom: 6px;
}

.modal-series {
  color: var(--ink-soft);
  font-size: 0.9rem;
  margin-bottom: 14px;
}

.modal-block { margin-bottom: 16px; }
.modal-block h4 {
  font-size: 0.85rem;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  color: var(--ink-soft);
  margin-bottom: 8px;
}
.modal-subject-list, .modal-feature-list {
  display: flex;
  flex-direction: column;
  gap: 7px;
}
.modal-subject-list li, .modal-feature-list li {
  font-size: 0.92rem;
  display: flex;
  align-items: flex-start;
  gap: 8px;
}
.modal-subject-list li::before { content: "📗"; flex-shrink: 0; }
.modal-feature-list li::before { content: "✔"; color: #2a9d5c; font-weight: 700; flex-shrink: 0; }

.modal-cta {
  display: flex;
  gap: 10px;
  margin-top: 20px;
  flex-wrap: wrap;
}

.modal-note {
  margin-top: 14px;
  font-size: 0.78rem;
  color: var(--ink-soft);
  background: var(--bg);
  padding: 10px 12px;
  border-radius: 10px;
}

/* ===== Responsive ===== */
@media (max-width: 860px) {
  .why-grid { grid-template-columns: repeat(2, 1fr); }
  .footer-inner { grid-template-columns: 1fr 1fr; }
  .modal-body { grid-template-columns: 1fr; }
}

@media (max-width: 720px) {
  .main-nav {
    position: fixed;
    top: 62px;
    left: 0;
    right: 0;
    background: #fff;
    flex-direction: column;
    padding: 16px 20px;
    gap: 4px;
    border-bottom: 1px solid var(--border);
    transform: translateY(-140%);
    transition: transform 0.2s ease;
    z-index: 99;
  }
  .main-nav.open { transform: translateY(0); }
  .main-nav a { padding: 10px 0; }
  .nav-toggle { display: flex; }
  .header-actions .btn-outline { display: none; }
  .book-row { grid-template-columns: repeat(auto-fit, minmax(148px, 1fr)); }
  .footer-inner { grid-template-columns: 1fr; }
}

@media (max-width: 480px) {
  .why-grid { grid-template-columns: 1fr; }
  .book-row { grid-template-columns: repeat(auto-fit, minmax(130px, 1fr)); gap: 14px; }
  .modal-body { padding: 20px; }
}