/* ==========================================================================
   AI Study Guru — 3D Full HD & Ultra-Premium Design System
   Top-Class 3D Physics · Glassmorphism · Glowing Mesh Orbs · Tactile Depth
   ========================================================================== */

:root {
  --hd-blue: #0052ff;
  --hd-indigo: #4f46e5;
  --hd-purple: #7c3aed;
  --hd-emerald: #10b981;
  --hd-amber: #f59e0b;
  --hd-cyan: #06b6d4;
  --hd-dark: #0a0f1d;
  --hd-card-bg: rgba(255, 255, 255, 0.88);
  --hd-card-border: rgba(255, 255, 255, 0.7);
  --hd-shadow-3d: 0 20px 45px -12px rgba(15, 23, 42, 0.12), 0 8px 16px -6px rgba(0, 82, 255, 0.08);
  --hd-shadow-hover: 0 30px 65px -15px rgba(0, 82, 255, 0.22), 0 14px 24px -8px rgba(15, 23, 42, 0.12);
}

/* ── 3D Full HD Atmosphere & Mesh Glows ──────────────────────────────────── */
.sg-hero {
  position: relative;
  overflow: hidden;
  background: 
    radial-gradient(ellipse 900px 600px at 15% 20%, rgba(99, 102, 241, 0.09), transparent 60%),
    radial-gradient(ellipse 700px 500px at 85% 30%, rgba(6, 182, 212, 0.1), transparent 55%),
    radial-gradient(ellipse 800px 600px at 50% 85%, rgba(124, 58, 237, 0.06), transparent 50%),
    linear-gradient(180deg, #f8faff 0%, #edf2ff 45%, #f1f5fb 100%) !important;
}

.sg-hero::before {
  content: "";
  position: absolute;
  top: -150px;
  right: -100px;
  width: 520px;
  height: 520px;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(0, 82, 255, 0.12) 0%, rgba(124, 58, 237, 0.04) 50%, transparent 70%);
  filter: blur(50px);
  pointer-events: none;
  animation: orbDrift 14s ease-in-out infinite alternate;
}

.sg-hero::after {
  content: "";
  position: absolute;
  bottom: -100px;
  left: -80px;
  width: 440px;
  height: 440px;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(16, 185, 129, 0.1) 0%, rgba(6, 182, 212, 0.03) 50%, transparent 70%);
  filter: blur(45px);
  pointer-events: none;
  animation: orbDrift 18s ease-in-out infinite alternate-reverse;
}

@keyframes orbDrift {
  0% { transform: translate(0, 0) scale(1); }
  50% { transform: translate(40px, -30px) scale(1.08); }
  100% { transform: translate(-30px, 40px) scale(0.95); }
}

/* ── 3D Gradient Text ────────────────────────────────────────────────────── */
.gradient-text-3d {
  background: linear-gradient(115deg, #0052ff 0%, #6366f1 35%, #8b5cf6 70%, #06b6d4 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  display: inline-block;
  filter: drop-shadow(0 2px 8px rgba(0, 82, 255, 0.25));
}

/* ── 3D Hero Demo Card (The Star Piece) ─────────────────────────────────── */
.hero-ai-demo-card {
  position: relative;
  border-radius: 24px !important;
  background: rgba(255, 255, 255, 0.94) !important;
  backdrop-filter: blur(28px) saturate(180%) !important;
  border: 1px solid rgba(255, 255, 255, 0.8) !important;
  box-shadow: 
    0 25px 60px -15px rgba(15, 23, 42, 0.16),
    0 0 0 1px rgba(0, 82, 255, 0.08) inset,
    0 1px 3px rgba(0, 0, 0, 0.04) !important;
  padding: 22px 24px !important;
  transform-style: preserve-3d;
  transition: transform 0.25s cubic-bezier(0.2, 0.8, 0.2, 1), box-shadow 0.25s ease;
}

.hero-ai-demo-card:hover {
  box-shadow: 
    0 35px 80px -18px rgba(0, 82, 255, 0.24),
    0 0 0 1px rgba(0, 82, 255, 0.16) inset !important;
}

.demo-live-badge {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  background: linear-gradient(135deg, rgba(16, 185, 129, 0.15), rgba(16, 185, 129, 0.06));
  border: 1px solid rgba(16, 185, 129, 0.35);
  color: #047857;
  font-size: 0.72rem;
  font-weight: 800;
  padding: 3px 10px;
  border-radius: 999px;
  letter-spacing: 0.05em;
  box-shadow: 0 2px 6px rgba(16, 185, 129, 0.15);
}

.demo-pulse {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: #10b981;
  box-shadow: 0 0 0 3px rgba(16, 185, 129, 0.35);
  animation: pulseGreen 1.8s infinite;
}

/* ── Interactive Demo Tab Strip ────────────────────────────────────────── */
.demo-tab-strip {
  display: flex;
  gap: 6px;
  margin: 14px 0 16px;
  padding: 4px;
  background: rgba(241, 245, 249, 0.85);
  border-radius: 12px;
  overflow-x: auto;
  scrollbar-width: none;
}

.demo-tab-strip::-webkit-scrollbar { display: none; }

.demo-tab-btn {
  flex: 0 0 auto;
  padding: 7px 12px;
  border-radius: 8px;
  font-size: 0.78rem;
  font-weight: 700;
  color: #64748b;
  border: none;
  background: transparent;
  cursor: pointer;
  transition: all 0.2s cubic-bezier(0.2, 0.8, 0.2, 1);
  display: inline-flex;
  align-items: center;
  gap: 5px;
  white-space: nowrap;
}

.demo-tab-btn:hover {
  color: #0f172a;
  background: rgba(255, 255, 255, 0.6);
}

.demo-tab-btn.active {
  background: #ffffff;
  color: #0052ff;
  box-shadow: 0 3px 10px rgba(0, 82, 255, 0.12), 0 1px 2px rgba(0, 0, 0, 0.06);
  transform: translateY(-1px);
}

/* ── Demo Tab Panel Content ────────────────────────────────────────────── */
.demo-tab-panel {
  display: none;
  animation: panelFadeIn 0.28s cubic-bezier(0.16, 1, 0.3, 1);
}

.demo-tab-panel.active {
  display: block;
}

@keyframes panelFadeIn {
  from { opacity: 0; transform: translateY(6px); }
  to { opacity: 1; transform: translateY(0); }
}

.demo-step-tag {
  display: inline-block;
  padding: 1px 6px;
  background: rgba(0, 82, 255, 0.09);
  color: #0052ff;
  font-weight: 700;
  border-radius: 4px;
  font-size: 0.72rem;
  margin-right: 4px;
}

.step-mark-head {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 8px;
  padding-bottom: 6px;
  border-bottom: 1px dashed rgba(203, 213, 225, 0.8);
  font-size: 0.8rem;
  font-weight: 700;
  color: #334155;
}

.marks-badge {
  background: linear-gradient(135deg, #0052ff, #4338ca);
  color: #ffffff;
  padding: 2px 8px;
  border-radius: 6px;
  font-size: 0.72rem;
  font-weight: 800;
  box-shadow: 0 2px 5px rgba(0, 82, 255, 0.25);
}

.trap-badge {
  background: #fef2f2;
  border: 1px solid #fecaca;
  color: #b91c1c;
  padding: 6px 10px;
  border-radius: 8px;
  font-size: 0.76rem;
  margin-top: 8px;
  display: flex;
  align-items: flex-start;
  gap: 6px;
}

.boxed-formula-gold {
  margin: 8px 0;
  padding: 8px 12px;
  border-radius: 8px;
  background: linear-gradient(135deg, #fffbeb, #fef3c7);
  border: 1.5px solid #f59e0b;
  color: #92400e;
  font-weight: 800;
  font-size: 0.95rem;
  text-align: center;
  box-shadow: 0 3px 8px rgba(245, 158, 11, 0.15);
}

/* ── 3D Floating Chips ─────────────────────────────────────────────────── */
.pg-float-chip {
  position: absolute;
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 10px 14px;
  border-radius: 14px;
  background: rgba(255, 255, 255, 0.92);
  backdrop-filter: blur(16px);
  border: 1px solid rgba(255, 255, 255, 0.85);
  box-shadow: 0 16px 32px -8px rgba(15, 23, 42, 0.14), 0 0 0 1px rgba(0, 82, 255, 0.08);
  font-size: 0.82rem;
  font-weight: 700;
  color: #0f172a;
  pointer-events: none;
  z-index: 5;
  animation: float3D 6s ease-in-out infinite alternate;
}

.pg-float-chip small {
  display: block;
  font-size: 0.7rem;
  font-weight: 500;
  color: #64748b;
  margin-top: 2px;
}

.pg-float-chip .pg-chip-ico {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 32px;
  height: 32px;
  border-radius: 8px;
  background: linear-gradient(135deg, #eff6ff, #dbeafe);
  font-size: 1.1rem;
}

.pg-chip-a {
  top: -16px;
  left: -20px;
  animation-delay: 0s;
}

.pg-chip-b {
  bottom: -18px;
  right: -16px;
  animation-delay: -2.5s;
}

.pg-chip-c {
  top: 45%;
  right: -28px;
  animation-delay: -4s;
}

@keyframes float3D {
  0% { transform: translateY(0px) rotate(0deg); }
  50% { transform: translateY(-8px) rotate(1deg); }
  100% { transform: translateY(6px) rotate(-1deg); }
}

@media (max-width: 900px) {
  .pg-float-chip { display: none !important; }
}

/* ── 3D Full HD Stats Grid ──────────────────────────────────────────────── */
.stats-strip-3d {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 16px;
  margin: 32px 0 0;
}

@media (max-width: 960px) {
  .stats-strip-3d { grid-template-columns: repeat(2, 1fr); gap: 12px; }
}
@media (max-width: 540px) {
  .stats-strip-3d { grid-template-columns: 1fr; }
}

.stat-card-3d {
  padding: 18px 20px;
  border-radius: 16px;
  background: rgba(255, 255, 255, 0.9);
  backdrop-filter: blur(14px);
  border: 1px solid rgba(255, 255, 255, 0.8);
  box-shadow: 0 10px 24px -6px rgba(15, 23, 42, 0.08);
  transition: transform 0.22s cubic-bezier(0.2, 0.8, 0.2, 1), box-shadow 0.22s ease;
  display: flex;
  align-items: center;
  gap: 14px;
}

.stat-card-3d:hover {
  transform: translateY(-4px);
  box-shadow: 0 16px 32px -8px rgba(0, 82, 255, 0.16);
}

.stat-icon-3d {
  width: 44px;
  height: 44px;
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.35rem;
  background: linear-gradient(135deg, rgba(0, 82, 255, 0.1), rgba(124, 58, 237, 0.1));
}

.stat-num-3d {
  font-size: 1.45rem;
  font-weight: 800;
  color: #0f172a;
  line-height: 1.1;
  letter-spacing: -0.02em;
}

.stat-label-3d {
  font-size: 0.78rem;
  color: #64748b;
  margin-top: 3px;
  font-weight: 600;
}

/* ── 3D Superpowers Grid ────────────────────────────────────────────────── */
.superpowers-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
  margin-top: 24px;
}

@media (max-width: 1024px) {
  .superpowers-grid { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 640px) {
  .superpowers-grid { grid-template-columns: 1fr; }
}

.superpower-card {
  padding: 24px 22px;
  border-radius: 20px;
  background: rgba(255, 255, 255, 0.94);
  backdrop-filter: blur(16px);
  border: 1px solid rgba(226, 232, 240, 0.9);
  box-shadow: 0 12px 30px -8px rgba(15, 23, 42, 0.08);
  transition: transform 0.25s cubic-bezier(0.2, 0.8, 0.2, 1), box-shadow 0.25s ease, border-color 0.25s ease;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  position: relative;
  overflow: hidden;
}

.superpower-card:hover {
  transform: translateY(-6px);
  box-shadow: 0 24px 50px -12px rgba(0, 82, 255, 0.18);
  border-color: rgba(0, 82, 255, 0.3);
}

.sp-badge-tag {
  display: inline-flex;
  align-items: center;
  gap: 5px;
  padding: 3px 10px;
  border-radius: 999px;
  font-size: 0.7rem;
  font-weight: 800;
  letter-spacing: 0.04em;
  margin-bottom: 12px;
  align-self: flex-start;
}

.tag-blue { background: rgba(0, 82, 255, 0.1); color: #0052ff; }
.tag-gold { background: rgba(245, 158, 11, 0.12); color: #b45309; }
.tag-purple { background: rgba(124, 58, 237, 0.12); color: #7c3aed; }
.tag-emerald { background: rgba(16, 185, 129, 0.12); color: #059669; }
.tag-cyan { background: rgba(6, 182, 212, 0.12); color: #0891b2; }

.sp-title {
  font-size: 1.15rem;
  font-weight: 800;
  color: #0f172a;
  margin-bottom: 8px;
  line-height: 1.3;
}

.sp-desc {
  font-size: 0.88rem;
  color: #475569;
  line-height: 1.6;
  margin-bottom: 14px;
}

.sp-highlights {
  display: flex;
  flex-direction: column;
  gap: 5px;
  margin-bottom: 18px;
  font-size: 0.78rem;
  font-weight: 600;
  color: #334155;
}

.sp-highlights span {
  display: flex;
  align-items: center;
  gap: 6px;
}

.sp-actions {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
  margin-top: auto;
}

/* ── 3D Channel Showcase Cards ──────────────────────────────────────────── */
.channel-comp-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
  margin-top: 24px;
}

@media (max-width: 980px) {
  .channel-comp-grid { grid-template-columns: 1fr; }
}

.channel-pill-card {
  padding: 26px 24px;
  border-radius: 20px;
  background: #ffffff;
  border: 1px solid #e2e8f0;
  box-shadow: 0 14px 35px -10px rgba(15, 23, 42, 0.08);
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  transition: transform 0.25s cubic-bezier(0.2, 0.8, 0.2, 1), box-shadow 0.25s ease;
  position: relative;
}

.channel-pill-card:hover {
  transform: translateY(-5px);
  box-shadow: 0 24px 50px -12px rgba(15, 23, 42, 0.14);
}

.channel-pill-card.featured-tg {
  border: 2px solid #0088cc;
  background: linear-gradient(180deg, #ffffff 0%, #f0f9ff 100%);
  box-shadow: 0 16px 40px -10px rgba(0, 136, 204, 0.22);
}

.channel-pill-card.featured-web {
  border: 2px solid #0052ff;
  background: linear-gradient(180deg, #ffffff 0%, #eff6ff 100%);
  box-shadow: 0 16px 40px -10px rgba(0, 82, 255, 0.22);
}

.channel-pill-title {
  font-size: 1.25rem;
  font-weight: 800;
  color: #0f172a;
  margin: 8px 0 10px;
}

.channel-pill-features {
  list-style: none;
  padding: 0;
  margin: 14px 0 22px;
  display: flex;
  flex-direction: column;
  gap: 8px;
  font-size: 0.84rem;
  color: #334155;
  font-weight: 600;
}

.channel-pill-features li {
  display: flex;
  align-items: center;
  gap: 8px;
}

.channel-pill-features li::before {
  content: "✓";
  color: #059669;
  font-weight: 900;
  font-size: 0.95rem;
}

/* ── 3D Competitive Exams Grid ─────────────────────────────────────────── */
.boards-grid-home {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 16px;
  margin-top: 22px;
}

@media (max-width: 1100px) {
  .boards-grid-home { grid-template-columns: repeat(3, 1fr); }
}
@media (max-width: 760px) {
  .boards-grid-home { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 480px) {
  .boards-grid-home { grid-template-columns: 1fr; }
}

.board-card-home {
  padding: 18px 18px;
  border-radius: 16px;
  background: #ffffff;
  border: 1px solid #e2e8f0;
  text-decoration: none;
  display: flex;
  flex-direction: column;
  transition: transform 0.2s cubic-bezier(0.2, 0.8, 0.2, 1), box-shadow 0.2s ease, border-color 0.2s ease;
}

.board-card-home:hover {
  transform: translateY(-4px);
  border-color: #0052ff;
  box-shadow: 0 14px 30px -8px rgba(0, 82, 255, 0.16);
}

.bch-icon {
  font-size: 1.6rem;
  margin-bottom: 8px;
}

.bch-title {
  font-size: 1.02rem;
  font-weight: 800;
  color: #0f172a;
  margin-bottom: 6px;
}

.bch-desc {
  font-size: 0.82rem;
  color: #64748b;
  line-height: 1.5;
  margin-bottom: 12px;
  flex: 1;
}

.bch-link {
  font-size: 0.78rem;
  font-weight: 700;
  color: #0052ff;
  display: inline-flex;
  align-items: center;
  gap: 4px;
}

/* ── Interactive 3D Pricing Grid ────────────────────────────────────────── */
.pricing-grid-3d {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 22px;
  margin-top: 28px;
  align-items: stretch;
}

@media (max-width: 900px) {
  .pricing-grid-3d { grid-template-columns: 1fr; }
}

.pricing-card-3d {
  padding: 30px 26px;
  border-radius: 24px;
  background: #ffffff;
  border: 1px solid #e2e8f0;
  box-shadow: 0 16px 36px -10px rgba(15, 23, 42, 0.08);
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  position: relative;
  transition: transform 0.25s ease, box-shadow 0.25s ease;
}

.pricing-card-3d:hover {
  transform: translateY(-6px);
  box-shadow: 0 25px 60px -15px rgba(15, 23, 42, 0.16);
}

.pricing-card-3d.featured-plan {
  border: 2px solid #7c3aed;
  background: linear-gradient(180deg, #ffffff 0%, #faf5ff 100%);
  box-shadow: 0 20px 50px -12px rgba(124, 58, 237, 0.25);
  transform: scale(1.02);
}

.pricing-card-3d.featured-plan:hover {
  transform: scale(1.02) translateY(-6px);
}

.plan-ribbon {
  position: absolute;
  top: -12px;
  right: 24px;
  background: linear-gradient(135deg, #7c3aed, #4f46e5);
  color: #ffffff;
  padding: 4px 14px;
  border-radius: 999px;
  font-size: 0.72rem;
  font-weight: 800;
  letter-spacing: 0.05em;
  box-shadow: 0 4px 12px rgba(124, 58, 237, 0.35);
}

.plan-price {
  font-size: 2.2rem;
  font-weight: 900;
  color: #0f172a;
  margin: 14px 0 6px;
  letter-spacing: -0.03em;
}

.plan-price small {
  font-size: 0.9rem;
  font-weight: 600;
  color: #64748b;
}

.plan-features {
  list-style: none;
  padding: 0;
  margin: 20px 0 24px;
  display: flex;
  flex-direction: column;
  gap: 10px;
  font-size: 0.85rem;
  color: #334155;
  font-weight: 600;
}

.plan-features li {
  display: flex;
  align-items: center;
  gap: 8px;
}

.plan-features li::before {
  content: "✓";
  color: #10b981;
  font-weight: 900;
}