:root {
  --primary-orange: #ff6b00;
  --primary-orange-hover: #e55e00;
  --primary-cyan: #00d4ff;
  --primary-blue: #0077b6;
  --primary-gold: #d97706;
  --gold-glow: #f59e0b;
  --bg-main: #f8fafc;
  --bg-card: #ffffff;
  --text-primary: #0f172a;
  --text-secondary: #475569;
  --text-muted: #64748b;
  --border-color: #e2e8f0;
  --radius-md: 12px;
  --radius-lg: 18px;
  --shadow-sm: 0 4px 6px -1px rgba(0, 0, 0, 0.05);
}

/* Smooth Scroll & Sticky Navbar Offset */
html {
  scroll-behavior: smooth;
  scroll-padding-top: 80px; /* Matches navbar height so headings are never cut off */
}

/* Section-to-Section Fade & Slide Transition */
.section-reveal {
  opacity: 0;
  transform: translateY(35px);
  transition: opacity 0.85s cubic-bezier(0.16, 1, 0.3, 1), transform 0.85s cubic-bezier(0.16, 1, 0.3, 1);
  will-change: opacity, transform;
}

.section-reveal.active {
  opacity: 1;
  transform: translateY(0);
}

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

body {
  font-family: 'Plus Jakarta Sans', sans-serif;
  background-color: var(--bg-main);
  color: var(--text-primary);
  line-height: 1.6;
  overflow-x: hidden;
}

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
}

.nav-links a.btn,
.mobile-nav-auth a,
.mobile-nav-auth .btn {
  color: #ffffff !important;
}

/* =============================================================
   AUTOMATIC AD PROMO POPUP (SEAMLESS PROPORTIONAL SCALING)
============================================================= */
.ad-modal-overlay {
  position: fixed;
  inset: 0;
  width: 100vw;
  height: 100vh;
  background: rgba(11, 19, 41, 0.85);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 100000;
  opacity: 0;
  visibility: hidden;
  transition: opacity 0.3s ease, visibility 0.3s ease;
  padding: 20px;
}

.ad-modal-overlay.active {
  opacity: 1;
  visibility: visible;
}

/* Container shrink-wraps the image with zero empty borders */
.ad-modal-container {
  position: relative;
  display: inline-flex;
  width: auto;
  height: auto;
  max-width: 92vw;
  max-height: 88vh;
  background: transparent; /* Removes the black letterbox background */
  border-radius: 16px;
  transform: scale(0.92);
  transition: transform 0.3s cubic-bezier(0.34, 1.56, 0.64, 1);
}

.ad-modal-overlay.active .ad-modal-container {
  transform: scale(1);
}

/* Image scales up naturally up to 88% screen height */
.ad-modal-img {
  display: block;
  width: auto;
  height: auto;
  max-width: 92vw;
  max-height: 86vh;
  border-radius: 16px;
  box-shadow: 0 25px 60px rgba(0, 0, 0, 0.8), 0 0 35px rgba(255, 122, 0, 0.45);
}

/* Close Button snapped to the top-right corner of the ad */
.ad-modal-close {
  position: absolute;
  top: -14px;
  right: -14px;
  width: 38px;
  height: 38px;
  background: #ff7a00;
  color: #ffffff;
  border: 2px solid #ffffff;
  border-radius: 50%;
  font-size: 1.4rem;
  font-weight: 800;
  line-height: 1;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: 0 4px 14px rgba(0, 0, 0, 0.6);
  z-index: 10;
  transition: transform 0.2s ease, background-color 0.2s ease;
}

.ad-modal-close:hover {
  background: #e55e00;
  transform: scale(1.12);
}

@media (max-width: 600px) {
  .ad-modal-img {
    max-height: 82vh;
    max-width: 88vw;
  }
  .ad-modal-close {
    top: -10px;
    right: -10px;
    width: 34px;
    height: 34px;
    font-size: 1.2rem;
  }
}

/* =============================================================
   REVISEUI BRAND THEMED MODALS, DIALOGS, ALERTS & TOASTS
============================================================= */
.revise-dialog-overlay {
  position: fixed;
  top: 0;
  left: 0;
  width: 100vw;
  height: 100vh;
  background: rgba(11, 19, 41, 0.75);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 10000;
  opacity: 0;
  visibility: hidden;
  transition: opacity 0.25s ease, visibility 0.25s ease;
  padding: 16px;
}

.revise-dialog-overlay.active {
  opacity: 1;
  visibility: visible;
}

.revise-dialog-box {
  background: #0f172a;
  border: 1.5px solid #1e293b;
  border-radius: 16px;
  width: 100%;
  max-width: 440px;
  box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.7), 0 0 24px rgba(255, 122, 0, 0.12);
  overflow: hidden;
  transform: scale(0.92) translateY(12px);
  transition: transform 0.25s cubic-bezier(0.34, 1.56, 0.64, 1);
  display: flex;
  flex-direction: column;
}

.revise-dialog-overlay.active .revise-dialog-box {
  transform: scale(1) translateY(0);
}

.revise-dialog-header {
  background: #1e293b;
  padding: 12px 18px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
}

.revise-dialog-brand {
  display: flex;
  align-items: center;
  gap: 10px;
}

.revise-dialog-logo {
  height: 24px;
  width: auto;
  filter: drop-shadow(0 2px 6px rgba(255, 122, 0, 0.4));
}

.revise-dialog-title {
  color: #f8fafc;
  font-size: 0.95rem;
  font-weight: 800;
  letter-spacing: 0.3px;
}

.revise-dialog-close {
  background: transparent;
  border: none;
  color: #94a3b8;
  font-size: 1.2rem;
  cursor: pointer;
  line-height: 1;
  transition: color 0.2s;
}

.revise-dialog-close:hover {
  color: #ff7a00;
}

.revise-dialog-body {
  padding: 24px 20px;
  text-align: center;
}

.revise-dialog-icon {
  font-size: 2.5rem;
  margin-bottom: 12px;
  display: inline-block;
}

.revise-dialog-icon.success { color: #10b981; }
.revise-dialog-icon.error { color: #ef4444; }
.revise-dialog-icon.warning { color: #f59e0b; }
.revise-dialog-icon.info { color: #00d4ff; }

.revise-dialog-heading {
  color: #ffffff;
  font-size: 1.2rem;
  font-weight: 800;
  margin-bottom: 8px;
}

.revise-dialog-message {
  color: #94a3b8;
  font-size: 0.92rem;
  line-height: 1.5;
  margin: 0;
}

.revise-dialog-footer {
  padding: 0 20px 20px;
  display: flex;
  gap: 10px;
}

.revise-dialog-brand .logo-revise {
  font-size: 0.98rem;
  font-weight: 800;
  background: linear-gradient(135deg, #ff9e00 0%, #ff5400 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.revise-dialog-brand .logo-it {
  font-size: 0.98rem;
  font-weight: 800;
  background: linear-gradient(135deg, #00d4ff 0%, #0077b6 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  padding-right: 2px;
  margin-right: 0;
}

.revise-dialog-title {
  color: #f8fafc;
  font-size: 0.95rem;
  font-weight: 800;
  letter-spacing: 0.3px;
  border-left: 1.5px solid #334155;
  padding-left: 8px;
  margin-left: 4px;
}

.btn-dialog-confirm {
  flex: 1;
  padding: 11px 16px;
  background: linear-gradient(135deg, #ff7a00 0%, #ff5400 100%);
  color: #ffffff;
  border: none;
  border-radius: 8px;
  font-weight: 800;
  font-size: 0.92rem;
  cursor: pointer;
  box-shadow: 0 4px 14px rgba(255, 122, 0, 0.3);
  transition: transform 0.2s, box-shadow 0.2s;
}

.btn-dialog-confirm:hover {
  transform: translateY(-1px);
  box-shadow: 0 6px 18px rgba(255, 122, 0, 0.5);
}

.btn-dialog-cancel {
  flex: 1;
  padding: 11px 16px;
  background: #1e293b;
  color: #cbd5e1;
  border: 1px solid #334155;
  border-radius: 8px;
  font-weight: 700;
  font-size: 0.92rem;
  cursor: pointer;
  transition: background 0.2s, color 0.2s;
}

.btn-dialog-cancel:hover {
  background: #334155;
  color: #ffffff;
}

.revise-toast-container {
  position: fixed;
  bottom: 24px;
  right: 24px;
  display: flex;
  flex-direction: column;
  gap: 10px;
  z-index: 10005;
}

.revise-toast {
  background: #0f172a;
  color: #ffffff;
  border: 1px solid #1e293b;
  border-left: 4px solid #ff7a00;
  padding: 14px 18px;
  border-radius: 10px;
  box-shadow: 0 10px 25px rgba(0, 0, 0, 0.5);
  font-size: 0.88rem;
  font-weight: 600;
  display: flex;
  align-items: center;
  gap: 12px;
  transform: translateX(120%);
  transition: transform 0.3s cubic-bezier(0.34, 1.56, 0.64, 1);
  max-width: 360px;
}

.revise-toast.active {
  transform: translateX(0);
}

.revise-toast.success { border-left-color: #10b981; }
.revise-toast.error { border-left-color: #ef4444; }
.revise-toast.info { border-left-color: #00d4ff; }

/* ==========================================================================
   Floating Action Buttons
   ========================================================================== */
.share-float {
  position: fixed;
  bottom: 98px;
  right: 28px;
  background: linear-gradient(135deg, #00d4ff 0%, #0077b6 100%);
  color: #ffffff;
  width: 54px;
  height: 54px;
  border-radius: 50%;
  border: none;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.5rem;
  box-shadow: 0 8px 24px rgba(0, 180, 216, 0.4);
  z-index: 9999;
  cursor: pointer;
  transition: transform 0.3s cubic-bezier(0.34, 1.56, 0.64, 1), box-shadow 0.3s ease;
}

.share-float:hover {
  transform: scale(1.15) rotate(8deg);
  box-shadow: 0 0 26px rgba(0, 212, 255, 0.8);
}

.share-tooltip {
  position: absolute;
  right: 66px;
  background: #0f172a;
  color: #ffffff;
  font-size: 0.82rem;
  font-weight: 700;
  padding: 6px 12px;
  border-radius: 8px;
  white-space: nowrap;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.25s ease, transform 0.25s ease;
  transform: translateX(10px);
}

.share-float:hover .share-tooltip {
  opacity: 1;
  transform: translateX(0);
}

.whatsapp-float {
  position: fixed;
  bottom: 28px;
  right: 28px;
  background-color: #25d366;
  color: #ffffff;
  width: 60px;
  height: 60px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 2rem;
  box-shadow: 0 8px 24px rgba(37, 211, 102, 0.4);
  z-index: 9999;
  text-decoration: none;
  transition: transform 0.3s cubic-bezier(0.34, 1.56, 0.64, 1), box-shadow 0.3s ease;
}

.whatsapp-float:hover {
  transform: scale(1.15) rotate(5deg);
  box-shadow: 0 0 28px rgba(37, 211, 102, 0.8);
}

.whatsapp-tooltip {
  position: absolute;
  right: 70px;
  background: #0f172a;
  color: #ffffff;
  font-size: 0.82rem;
  font-weight: 700;
  padding: 6px 12px;
  border-radius: 8px;
  white-space: nowrap;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.25s ease, transform 0.25s ease;
  transform: translateX(10px);
}

.whatsapp-float:hover .whatsapp-tooltip {
  opacity: 1;
  transform: translateX(0);
}

/* ==========================================================================
   Brand Logos
   ========================================================================== */
.brand-logo {
  text-decoration: none;
  display: inline-flex;
  align-items: center;
  cursor: pointer;
}

.nav-logo-img {
  height: 96px;
  width: auto;
  max-width: 440px;
  object-fit: contain;
  display: block;
  transition: transform 0.3s cubic-bezier(0.34, 1.56, 0.64, 1), filter 0.3s ease;
}

.brand-logo:hover .nav-logo-img {
  transform: scale(1.05);
  filter: drop-shadow(0 4px 12px rgba(255, 107, 0, 0.35));
}

.footer-logo-link {
  display: inline-block;
  margin-bottom: 0;
}

.footer-logo-img {
  height: 104px;
  width: auto;
  max-width: 460px;
  object-fit: contain;
  display: block;
  filter: brightness(1.05);
  transition: transform 0.3s ease, filter 0.3s ease;
}

.footer-logo-link:hover .footer-logo-img {
  transform: scale(1.04);
  filter: brightness(1.15) drop-shadow(0 4px 14px rgba(0, 212, 255, 0.3));
}

.logo-revise {
  display: inline-block;
  background: linear-gradient(135deg, #ff9e00 0%, #ff5400 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  font-weight: 800;
}

.logo-it {
  display: inline-block;
  background: linear-gradient(135deg, #00d4ff 0%, #0077b6 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  font-style: normal;
  font-weight: 800;
  padding-right: 10px;
  margin-right: -6px;
}

/* ==========================================================================
   Navbar
   ========================================================================== */
.navbar {
  background: rgba(255, 255, 255, 0.94);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border-color);
  position: sticky;
  top: 0;
  z-index: 1000;
  box-shadow: var(--shadow-sm);
}

.nav-container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 80px;
}

.nav-links {
  display: flex;
  gap: 32px;
}

.nav-links a {
  text-decoration: none;
  color: var(--text-secondary);
  font-weight: 700;
  font-size: 1.05rem;
  display: inline-block;
  transition: transform 0.25s cubic-bezier(0.34, 1.56, 0.64, 1), color 0.25s ease, filter 0.25s ease;
}

.nav-links a:hover {
  color: var(--primary-blue);
  transform: scale(1.08);
  filter: drop-shadow(0 4px 8px rgba(0, 119, 182, 0.25));
}

.auth-buttons {
  display: flex;
  gap: 12px;
}

.mobile-toggle {
  display: none;
  background: none;
  border: none;
  font-size: 1.5rem;
  color: var(--text-primary);
  cursor: pointer;
}

/* ==========================================================================
   Buttons
   ========================================================================== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 10px 22px;
  font-size: 0.98rem;
  font-weight: 700;
  border-radius: 10px;
  cursor: pointer;
  text-decoration: none;
  transition: all 0.3s cubic-bezier(0.34, 1.56, 0.64, 1);
  border: none;
}

.btn-signin {
  background: linear-gradient(135deg, #ff7a00 0%, #ff5400 100%);
  color: #ffffff;
  box-shadow: 0 4px 14px rgba(255, 107, 0, 0.25);
}

.btn-signin:hover {
  transform: scale(1.04);
  box-shadow: 0 0 16px rgba(255, 107, 0, 0.55);
}

.btn-signup {
  background: linear-gradient(135deg, #00d4ff 0%, #0077b6 100%);
  color: #ffffff;
  box-shadow: 0 4px 14px rgba(0, 180, 216, 0.3);
}

.btn-signup:hover {
  transform: scale(1.04);
  box-shadow: 0 0 18px rgba(0, 212, 255, 0.6);
  color: #ffffff;
}

.btn-why-revise {
  background: #0f172a;
  color: #ffffff;
  border: 1.5px solid rgba(255, 255, 255, 0.15);
  box-shadow: 0 4px 14px rgba(15, 23, 42, 0.2);
}

.btn-why-revise:hover {
  background: linear-gradient(135deg, #00d4ff 0%, #0077b6 100%);
  color: #ffffff;
  transform: scale(1.04);
  border-color: transparent;
  box-shadow: 0 0 18px rgba(0, 212, 255, 0.6);
}

.btn-why-revise .logo-revise,
.btn-why-revise .logo-it {
  transition: all 0.3s ease;
}

.btn-why-revise:hover .logo-revise,
.btn-why-revise:hover .logo-it {
  background: none;
  -webkit-background-clip: unset;
  -webkit-text-fill-color: #ffffff;
  color: #ffffff;
  filter: none;
}

.btn-gold {
  background: linear-gradient(135deg, #f59e0b 0%, #d97706 100%);
  color: #ffffff;
  box-shadow: 0 4px 14px rgba(217, 119, 6, 0.3);
}

.btn-gold:hover {
  box-shadow: 0 0 16px rgba(245, 158, 11, 0.7);
  transform: scale(1.03);
}

.btn-success { background: #10b981; color: #fff; }
.btn-large { padding: 13px 26px; font-size: 1.02rem; }
.btn-block { width: 100%; }

/* ==========================================================================
   Hero Section - Modern Interactive EdTech Architecture
   ========================================================================== */
.hero-section {
  position: relative;
  background: radial-gradient(circle at 20% 20%, rgba(255, 122, 0, 0.08) 0%, transparent 45%),
              radial-gradient(circle at 80% 80%, rgba(2, 132, 199, 0.08) 0%, transparent 45%),
              #ffffff;
  padding: 60px 0 80px;
  overflow: hidden;
}

.hero-grid-wrap {
  display: grid;
  grid-template-columns: 1.15fr 0.85fr;
  gap: 48px;
  align-items: center;
}

/* Left Content Column */
.hero-badge-pill {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: rgba(255, 122, 0, 0.1);
  border: 1px solid rgba(255, 122, 0, 0.25);
  color: #ea580c;
  padding: 6px 14px;
  border-radius: 30px;
  font-size: 0.82rem;
  font-weight: 800;
  margin-bottom: 20px;
}

.hero-badge-pill i {
  color: #ff7a00;
  animation: pulseBadge 2s infinite ease-in-out;
}

.hero-main-heading {
  font-size: 2.85rem;
  line-height: 1.18;
  font-weight: 900;
  color: #0f172a;
  letter-spacing: -0.8px;
  margin-bottom: 18px;
}

/* Hero Subtext MHT-CET Vibrant Green Accent Highlight */
.hero-highlight-accent {
  display: inline-block;
  font-weight: 800;
  background: linear-gradient(135deg, rgba(34, 197, 94, 0.14) 0%, rgba(21, 128, 61, 0.08) 100%);
  border: 1px solid rgba(22, 163, 74, 0.38);
  padding: 2px 10px;
  border-radius: 8px;
  margin-right: 4px;
  box-shadow: 0 2px 8px rgba(34, 197, 94, 0.15);
}

.hero-highlight-accent .green-text {
  background: linear-gradient(135deg, #16a34a 0%, #15803d 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  font-weight: 900;
  letter-spacing: -0.2px;
}

.hero-main-heading .gradient-brand {
  background: linear-gradient(135deg, #ff7a00, #ff5400);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.hero-main-heading .target-board {
  color: #15803d;
  position: relative;
  display: inline-block;
}

.hero-feature-pills {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-bottom: 22px;
}

.feature-pill-item {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  background: #f8fafc;
  border: 1px solid #e2e8f0;
  color: #334155;
  font-size: 0.82rem;
  font-weight: 700;
  padding: 6px 12px;
  border-radius: 8px;
}

.feature-pill-item i {
  color: #0284c7;
}

.hero-subtext {
  font-size: 1.02rem;
  line-height: 1.6;
  color: #64748b;
  margin-bottom: 28px;
  max-width: 540px;
}

.hero-cta-group {
  display: flex;
  align-items: center;
  gap: 14px;
  flex-wrap: wrap;
  margin-bottom: 28px;
}

.hero-cta-group .btn-large {
  padding: 14px 28px;
  font-size: 0.98rem;
  font-weight: 800;
  border-radius: 10px;
}

.hero-social-proof {
  display: flex;
  align-items: center;
  gap: 12px;
  font-size: 0.86rem;
  color: #64748b;
}

.hero-stars {
  color: #f59e0b;
  font-weight: 800;
  letter-spacing: 1px;
}

/* Right Interactive Visual Card */
.hero-visual-card-wrap {
  position: relative;
}

.hero-interactive-card {
  background: #0f172a;
  border: 1.5px solid #1e293b;
  border-radius: 18px;
  padding: 24px;
  box-shadow: 0 25px 50px -12px rgba(15, 23, 42, 0.25);
  color: #ffffff;
  position: relative;
  z-index: 2;
  min-height: 290px;
}

.card-top-status {
  display: flex;
  justify-content: space-between;
  align-items: center;
  border-bottom: 1px solid #1e293b;
  padding-bottom: 14px;
  margin-bottom: 18px;
}

.subject-tag {
  background: #1e293b;
  color: #38bdf8;
  font-size: 0.76rem;
  font-weight: 800;
  padding: 4px 10px;
  border-radius: 6px;
  text-transform: uppercase;
  transition: color 0.35s ease, background 0.35s ease;
}

.pulse-indicator {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: 0.76rem;
  color: #10b981;
  font-weight: 700;
}

.pulse-dot {
  width: 8px;
  height: 8px;
  background: #10b981;
  border-radius: 50%;
  box-shadow: 0 0 0 0 rgba(16, 185, 129, 0.7);
  animation: pulseDot 1.8s infinite;
}

/* Dynamic Rotating Card Body Transitions */
.hero-card-dynamic-body {
  transition: opacity 0.32s cubic-bezier(0.4, 0, 0.2, 1), transform 0.32s cubic-bezier(0.4, 0, 0.2, 1);
  will-change: opacity, transform;
}

.hero-card-dynamic-body.switching {
  opacity: 0;
  transform: translateY(8px);
}

.card-sample-title {
  font-size: 1.12rem;
  font-weight: 800;
  color: #ffffff;
  margin-bottom: 6px;
}

.card-sample-subtitle {
  font-size: 0.82rem;
  color: #94a3b8;
  margin-bottom: 16px;
}

.sample-formula-box {
  background: #1e293b;
  border: 1px dashed #334155;
  border-radius: 10px;
  padding: 12px 14px;
  margin-bottom: 14px;
}

.formula-label {
  font-size: 0.72rem;
  text-transform: uppercase;
  color: #ff7a00;
  font-weight: 800;
  display: block;
  margin-bottom: 4px;
}

/* Textbook Mathematical Typography Engine */
.formula-math {
  font-family: 'Cambria Math', 'STIX Two Math', 'Times New Roman', Georgia, serif;
  font-size: 1.05rem;
  color: #f8fafc;
  font-weight: 600;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-wrap: wrap;
  gap: 12px;
  min-height: 46px;
  line-height: 1.35;
}

.math-expr {
  display: inline-flex;
  align-items: center;
  white-space: nowrap;
}

.math-sym-sep {
  color: #ff7a00;
  font-size: 0.85rem;
  margin: 0 4px;
  user-select: none;
}

.math-var {
  font-style: italic;
  padding: 0 1.5px;
}

/* Authentic Fraction Layout */
.math-frac {
  display: inline-flex;
  flex-direction: column;
  vertical-align: middle;
  text-align: center;
  padding: 0 3px;
  font-size: 0.88em;
  margin: 0 2px;
}

.math-num {
  border-bottom: 1.5px solid #cbd5e1;
  padding-bottom: 2px;
  line-height: 1;
}

.math-den {
  padding-top: 2px;
  line-height: 1;
}

/* Continuous Vinculum Radical (Square Root) */
.math-sqrt {
  display: inline-flex;
  align-items: stretch;
  margin-left: 2px;
}

.math-sqrt-radical {
  font-size: 1.25em;
  line-height: 0.95;
  margin-right: -1px;
  transform: translateY(1px);
}

.math-sqrt-radicand {
  border-top: 1.5px solid #cbd5e1;
  padding: 1px 4px 0 2px;
  display: inline-flex;
  align-items: center;
  margin-top: 1px;
}

/* Definite Integral with Upper & Lower Limits */
.math-integral {
  display: inline-flex;
  align-items: center;
  margin-right: 2px;
}

.math-int-sym {
  font-size: 1.45em;
  line-height: 1;
  font-style: normal;
}

.math-int-limits {
  display: inline-flex;
  flex-direction: column;
  font-size: 0.65em;
  line-height: 0.9;
  margin-left: -2px;
  margin-right: 3px;
}

.math-int-limits .upper {
  transform: translateY(-2px);
}

.math-int-limits .lower {
  transform: translateY(2px);
}

.formula-math sub {
  font-size: 0.72em;
  line-height: 0;
  vertical-align: -0.35em;
}

.formula-math sup {
  font-size: 0.72em;
  line-height: 0;
  vertical-align: 0.45em;
}

.sample-trap-box {
  background: rgba(239, 68, 68, 0.08);
  border-left: 3px solid #ef4444;
  padding: 10px 12px;
  border-radius: 0 8px 8px 0;
  font-size: 0.8rem;
  color: #fca5a5;
  line-height: 1.4;
}

/* Floating Badges with CSS micro-animations */
.floating-badge {
  position: absolute;
  background: #ffffff;
  border: 1px solid #e2e8f0;
  padding: 10px 14px;
  border-radius: 12px;
  box-shadow: 0 14px 28px rgba(0, 0, 0, 0.08);
  display: flex;
  align-items: center;
  gap: 10px;
  z-index: 3;
}

.floating-badge-1 {
  top: -24px;
  right: -16px;
  animation: floatBadge1 4s ease-in-out infinite;
}

.floating-badge-2 {
  bottom: -22px;
  left: -20px;
  animation: floatBadge2 4.5s ease-in-out infinite;
}

.float-icon {
  width: 34px;
  height: 34px;
  border-radius: 8px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.95rem;
}

.float-icon.orange { background: #fff7ed; color: #ff7a00; }
.float-icon.green { background: #f0fdf4; color: #16a34a; }
.float-title { font-size: 0.8rem; font-weight: 800; color: #0f172a; margin: 0; }
.float-sub { font-size: 0.7rem; color: #64748b; margin: 0; }

/* Micro-Animations Keyframes */
@keyframes floatBadge1 {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-8px); }
}

@keyframes floatBadge2 {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(8px); }
}

@keyframes pulseBadge {
  0%, 100% { transform: scale(1); }
  50% { transform: scale(1.15); }
}

@keyframes pulseDot {
  0% { box-shadow: 0 0 0 0 rgba(16, 185, 129, 0.7); }
  70% { box-shadow: 0 0 0 8px rgba(16, 185, 129, 0); }
  100% { box-shadow: 0 0 0 0 rgba(16, 185, 129, 0); }
}

/* ==========================================================================
   Features Section
   ========================================================================== */
.features-section {
  padding: 75px 0 85px;
  background: #ffffff;
  border-top: 1px solid var(--border-color);
  border-bottom: 1px solid var(--border-color);
}

.section-header { 
  text-align: center; 
  margin-bottom: 44px; 
}

.badge-recall {
  display: inline-block;
  background: #f1f5f9;
  color: #475569;
  font-size: 0.76rem;
  font-weight: 800;
  padding: 6px 16px;
  border-radius: 999px;
  margin-bottom: 12px;
  text-transform: uppercase;
  letter-spacing: 0.6px;
  border: 1px solid #e2e8f0;
}

.features-main-title {
  font-size: 2.25rem;
  font-weight: 800;
  color: #0f172a;
  letter-spacing: -0.5px;
}

.text-smart-choice {
  color: #16a34a;
  font-weight: 800;
}

.features-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 22px;
}

.feature-card {
  padding: 32px 22px 28px;
  border-radius: 20px;
  text-align: center;
  display: flex;
  flex-direction: column;
  align-items: center;
  box-shadow: 0 8px 24px rgba(0, 0, 0, 0.03);
  transition: transform 0.3s cubic-bezier(0.34, 1.56, 0.64, 1), box-shadow 0.3s ease, border-color 0.3s ease;
}

.feature-card:hover { 
  transform: translateY(-6px); 
}

.feature-card-orange {
  background: linear-gradient(180deg, #fff9f2 0%, #ffffff 65%);
  border: 1.5px solid #fed7aa;
}
.feature-card-orange:hover {
  border-color: #fb923c;
  box-shadow: 0 16px 32px rgba(249, 115, 22, 0.12);
}

.feature-card-blue {
  background: linear-gradient(180deg, #f0f9ff 0%, #ffffff 65%);
  border: 1.5px solid #bae6fd;
}
.feature-card-blue:hover {
  border-color: #38bdf8;
  box-shadow: 0 16px 32px rgba(14, 165, 233, 0.12);
}

.feature-card-purple {
  background: linear-gradient(180deg, #f5f3ff 0%, #ffffff 65%);
  border: 1.5px solid #ddd6fe;
}
.feature-card-purple:hover {
  border-color: #818cf8;
  box-shadow: 0 16px 32px rgba(99, 102, 241, 0.12);
}

.feature-card-green {
  background: linear-gradient(180deg, #f0fdf4 0%, #ffffff 65%);
  border: 1.5px solid #bbf7d0;
}
.feature-card-green:hover {
  border-color: #4ade80;
  box-shadow: 0 16px 32px rgba(34, 197, 94, 0.12);
}

.feature-icon-wrap {
  width: 64px;
  height: 64px;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 20px;
}

.feat-svg {
  width: 100%;
  height: 100%;
  filter: drop-shadow(0 4px 8px rgba(0, 0, 0, 0.05));
}

.feature-card h3 {
  font-size: 1.15rem;
  font-weight: 800;
  color: #0f172a;
  margin-bottom: 10px;
  line-height: 1.35;
}

.feature-card p {
  font-size: 0.9rem;
  color: #475569;
  line-height: 1.55;
  margin: 0;
}

/* ==========================================================================
   Courses Section
   ========================================================================== */
.courses-section {
  padding: 80px 0;
}

.courses-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(270px, 1fr));
  gap: 28px;
}

.course-card {
  background: #ffffff;
  border-radius: var(--radius-lg);
  border: 1.5px solid var(--border-color);
  box-shadow: var(--shadow-sm);
  overflow: hidden;
  display: flex;
  flex-direction: column;
  position: relative;
  transition: transform 0.3s cubic-bezier(0.34, 1.56, 0.64, 1), box-shadow 0.3s ease, border-color 0.3s ease;
}

.course-card:not(.gold-course-card):hover {
  transform: translateY(-8px);
  border-color: #00b4d8;
  box-shadow: 0 0 25px 4px rgba(0, 180, 216, 0.45), 0 15px 30px rgba(0, 119, 182, 0.2);
}

.course-card.gold-course-card {
  border: 2px solid #f59e0b;
}

.course-card.gold-course-card:hover {
  transform: translateY(-8px);
  border-color: #fbbf24;
  box-shadow: 0 0 30px 6px rgba(245, 158, 11, 0.55), 0 15px 35px rgba(217, 119, 6, 0.3);
}

.course-card.gold-course-card .popular-ribbon {
  background: linear-gradient(135deg, #d97706, #f59e0b);
}

.popular-ribbon {
  position: absolute;
  top: 14px;
  right: -32px;
  background: var(--primary-cyan);
  color: #fff;
  font-size: 0.72rem;
  font-weight: 800;
  text-transform: uppercase;
  padding: 4px 34px;
  transform: rotate(45deg);
  box-shadow: 0 2px 6px rgba(0, 0, 0, 0.1);
  z-index: 5;
}

.course-thumb {
  height: 165px;
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: center;
  position: relative;
  overflow: hidden;
  background: #0f172a;
  border-top-left-radius: calc(var(--radius-lg) - 1.5px);
  border-top-right-radius: calc(var(--radius-lg) - 1.5px);
}

.course-thumb-img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
  transition: transform 0.35s cubic-bezier(0.34, 1.56, 0.64, 1);
}

.course-card:hover .course-thumb-img {
  transform: scale(1.05);
}

/* Forest Green Hover Effect for Biology Course */
.courses-grid .course-card.bio-course-card:hover {
  transform: translateY(-8px);
  border-color: #16a34a;
  box-shadow: 0 0 25px 4px rgba(34, 197, 94, 0.45), 0 15px 30px rgba(21, 128, 61, 0.25);
}

.pdf-tag {
  position: absolute;
  top: 12px;
  left: 12px;
  background: rgba(15, 23, 42, 0.82);
  color: #ffffff;
  font-size: 0.75rem;
  font-weight: 700;
  padding: 5px 12px;
  border-radius: 6px;
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  border: 1px solid rgba(255, 255, 255, 0.18);
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.35);
  z-index: 3;
}

.coming-soon-card {
  padding: 0 !important;
  overflow: hidden;
  border: 2px dashed #00d4ff !important;
  background: #0f172a;
  position: relative;
  display: flex;
  flex-direction: column;
  justify-content: stretch;
  cursor: default;
}

.coming-soon-card:hover {
  transform: translateY(-8px);
  border-color: #ff7a00 !important;
  box-shadow: 0 0 30px 6px rgba(255, 122, 0, 0.45), 0 15px 35px rgba(0, 0, 0, 0.3) !important;
}

.coming-soon-ribbon {
  background: linear-gradient(135deg, #ff7a00, #ff5400) !important;
  top: 18px !important;
  right: -34px !important;
  padding: 5px 36px !important;
  font-size: 0.72rem !important;
  z-index: 5;
}

.coming-soon-poster-wrap {
  width: 100%;
  height: 100%;
  display: flex;
}

.coming-soon-poster {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
}

.course-body {
  padding: 22px;
  display: flex;
  flex-direction: column;
  flex-grow: 1;
}

.course-body h3 {
  font-size: 1.2rem;
  font-weight: 700;
  margin-bottom: 8px;
  line-height: 1.35;
}

.course-desc {
  font-size: 0.88rem;
  color: var(--text-secondary);
  margin-bottom: 16px;
  min-height: 42px;
}

.meta-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-bottom: 14px;
  margin-bottom: 14px;
  border-bottom: 1px dashed var(--border-color);
  font-size: 0.84rem;
}

.stars { color: #f59e0b; font-size: 0.95rem; }
.rating-count { font-weight: 700; color: var(--text-primary); margin-left: 4px; }
.downloads { color: var(--text-muted); font-weight: 600; }
.downloads i { color: var(--primary-cyan); margin-right: 4px; }

.pricing-box {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 6px;
}

.current-price { font-size: 1.55rem; font-weight: 800; color: #0f172a; }
.original-price { font-size: 0.95rem; color: var(--text-muted); text-decoration: line-through; margin-left: 6px; }
.discount-badge { background: #dcfce7; color: #15803d; font-size: 0.78rem; font-weight: 700; padding: 3px 8px; border-radius: 6px; }
.gold-discount { background: #fef3c7; color: #b45309; }

.deadline-note {
  font-size: 0.82rem;
  font-weight: 600;
  color: #dc2626;
  margin-bottom: 18px;
  display: flex;
  align-items: center;
  gap: 6px;
}

.deadline-note i {
  color: #dc2626;
  font-size: 0.9rem;
}

.deadline-date {
  font-size: 0.96rem;
  font-weight: 800;
  text-decoration: underline;
  text-underline-offset: 3px;
  color: #dc2626;
}

.deadline-date sup {
  font-size: 0.65em;
  vertical-align: super;
}

.review-carousel {
  margin-top: 18px;
  padding-top: 12px;
  border-top: 1px solid var(--border-color);
  position: relative;
  display: flex;
  align-items: center;
  gap: 8px;
}

.carousel-track-container {
  overflow: hidden;
  position: relative;
  width: 100%;
  min-height: 80px;
}

.carousel-track {
  position: relative;
  width: 100%;
  min-height: 80px;
}

.review-slide {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  opacity: 0;
  transform: translateX(20px);
  transition: opacity 0.3s ease, transform 0.3s ease;
  pointer-events: none;
  display: none;
}

.review-slide.active {
  opacity: 1;
  transform: translateX(0);
  position: relative;
  pointer-events: auto;
  display: block;
}

.review-slide p {
  font-style: italic;
  font-size: 0.82rem;
  color: var(--text-secondary);
  line-height: 1.4;
}

.review-slide .reviewer-name {
  display: block;
  font-style: normal;
  font-weight: 700;
  font-size: 0.76rem;
  color: var(--primary-blue);
  margin-top: 5px;
}

.carousel-btn {
  background: #f1f5f9;
  border: 1px solid var(--border-color);
  color: var(--text-secondary);
  width: 26px;
  height: 26px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.72rem;
  cursor: pointer;
  flex-shrink: 0;
  transition: all 0.2s ease;
}

.carousel-btn:hover {
  background: var(--primary-cyan);
  color: #ffffff;
  border-color: var(--primary-cyan);
}

/* ==========================================================================
   Footer & Contact Us Section
   ========================================================================== */
.footer {
  background: #0b1329;
  color: #ffffff;
  padding: 60px 0 35px;
}

.footer-top {
  display: grid;
  grid-template-columns: 1.2fr 1fr;
  gap: 50px;
  padding-bottom: 45px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}

.footer-brand .footer-desc {
  font-size: 0.88rem;
  color: #94a3b8;
  max-width: 380px;
  margin-top: 2px;
  line-height: 1.5;
}

.footer-contact {
  display: flex;
  flex-direction: column;
  align-items: flex-end;
  text-align: right;
}

.footer-heading {
  font-size: 1.25rem;
  font-weight: 800;
  color: #ffffff;
  margin-bottom: 6px;
  position: relative;
  display: inline-block;
}

.footer-heading::after {
  content: '';
  position: absolute;
  right: 0;
  bottom: -4px;
  width: 35px;
  height: 3px;
  background: var(--primary-orange);
  border-radius: 2px;
}

.contact-sub {
  font-size: 0.95rem;
  font-weight: 600;
  color: #94a3b8;
  margin-top: 6px;
  margin-bottom: 18px;
}

.contact-links {
  display: flex;
  flex-direction: column;
  align-items: flex-end;
  gap: 12px;
}

.contact-pill {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  text-decoration: none;
  font-size: 0.92rem;
  font-weight: 600;
  padding: 10px 18px;
  border-radius: 10px;
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid rgba(255, 255, 255, 0.1);
  color: #e2e8f0;
  width: fit-content;
  transition: transform 0.25s cubic-bezier(0.34, 1.56, 0.64, 1), background 0.25s ease, border-color 0.25s ease;
}

.contact-pill i { font-size: 1.2rem; }
.email-pill i { color: #38bdf8; }
.insta-pill i { color: #f43f5e; }

.contact-pill:hover {
  transform: translateX(-6px) scale(1.03);
  background: rgba(255, 255, 255, 0.12);
  border-color: rgba(255, 255, 255, 0.25);
  color: #ffffff;
}

.footer-bottom {
  padding-top: 32px;
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  align-items: center;
  gap: 16px;
}

.footer-legal-links {
  display: flex;
  align-items: center;
  gap: 10px;
  flex-wrap: wrap;
}

.legal-link-btn {
  background: none;
  border: none;
  padding: 0;
  color: #94a3b8;
  font-family: inherit;
  font-size: 0.82rem;
  font-weight: 600;
  cursor: pointer;
  transition: color 0.2s ease;
}

.legal-link-btn:hover {
  color: var(--primary-cyan);
  text-decoration: underline;
  text-underline-offset: 3px;
}

.legal-separator {
  color: #475569;
  font-size: 0.75rem;
}

.copyright-text {
  font-size: 0.84rem;
  color: #64748b;
  margin: 0;
  text-align: center;
  white-space: nowrap;
}

.developer-credit {
  font-size: 0.84rem;
  color: #94a3b8;
  margin: 0;
  text-align: right;
  white-space: nowrap;
}

.aayanspace-link {
  font-weight: 800;
  color: #f59e0b;
  text-decoration: none;
  letter-spacing: 0.3px;
  transition: color 0.2s ease, text-shadow 0.2s ease;
}

.aayanspace-link:hover {
  color: #fbbf24;
  text-shadow: 0 0 10px rgba(245, 158, 11, 0.6);
  text-decoration: underline;
  text-underline-offset: 3px;
}

/* =============================================================
   FULLY RESPONSIVE & TOOLBAR-FREE DOCUMENT VIEWER MODAL
============================================================= */
.doc-modal-card {
  width: 95vw !important;
  max-width: 1100px !important;
  height: 92vh !important;
  max-height: 92vh !important;
  padding: 0 !important;
  margin: 0 !important;
  background: #0f172a !important;
  border: 1.5px solid #334155 !important;
  border-radius: 16px !important;
  box-shadow: 0 25px 60px -15px rgba(0, 0, 0, 0.75) !important;
  display: flex !important;
  flex-direction: column !important;
  overflow: hidden !important;
}

.doc-modal-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 12px 18px;
  background: #0f172a;
  color: #ffffff;
  border-bottom: 1px solid #1e293b;
  user-select: none;
  flex-shrink: 0;
  gap: 10px;
}

.doc-modal-title-wrap {
  display: flex;
  align-items: center;
  gap: 10px;
  min-width: 0;
}

.doc-modal-icon {
  color: #38bdf8;
  font-size: 1.2rem;
  flex-shrink: 0;
}

.doc-modal-header h3 {
  font-size: 1.05rem;
  font-weight: 700;
  color: #f8fafc;
  margin: 0;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.doc-modal-controls {
  display: flex;
  align-items: center;
  gap: 6px;
  flex-shrink: 0;
}

.doc-ctrl-btn {
  background: #1e293b;
  border: 1px solid #334155;
  color: #cbd5e1;
  font-size: 0.82rem;
  font-weight: 600;
  height: 32px;
  min-width: 32px;
  padding: 0 10px;
  border-radius: 6px;
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  transition: all 0.2s ease;
}

.doc-ctrl-btn:hover {
  background: #334155;
  color: #ffffff;
  border-color: #475569;
}

.doc-zoom-level {
  font-size: 0.82rem;
  font-weight: 700;
  color: #94a3b8;
  min-width: 44px;
  text-align: center;
}

.doc-ctrl-divider {
  width: 1px;
  height: 18px;
  background: #334155;
  margin: 0 2px;
}

.doc-close-btn {
  background: rgba(239, 68, 68, 0.15);
  border: 1px solid rgba(239, 68, 68, 0.3);
  color: #fca5a5;
  height: 32px;
  width: 32px;
  border-radius: 6px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  font-size: 1.1rem;
  cursor: pointer;
  transition: all 0.2s ease;
}

.doc-close-btn:hover {
  background: #ef4444;
  color: #ffffff;
  border-color: #ef4444;
}

/* Document Body & Multi-Page Render Container */
.doc-modal-body {
  flex: 1;
  width: 100%;
  height: 100%;
  background: #1e293b;
  overflow-y: auto;
  overflow-x: auto;
  position: relative;
  display: flex;
  flex-direction: column;
  align-items: center;
  padding: 24px 16px;
  -webkit-overflow-scrolling: touch;
}

.doc-loader {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 12px;
  color: #94a3b8;
  font-size: 0.95rem;
  font-weight: 600;
  margin: auto;
  padding: 40px;
}

.doc-loader i {
  font-size: 2rem;
  color: #38bdf8;
}

.doc-pages-container {
  display: flex;
  flex-direction: column;
  align-items: center;
  width: 100%;
  gap: 20px;
}

.pdf-page-wrapper {
  background: #ffffff;
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.45);
  border-radius: 4px;
  overflow: hidden;
  max-width: 100%;
  transition: transform 0.15s ease;
}

.pdf-page-wrapper canvas {
  display: block;
  max-width: 100%;
  height: auto !important;
}

/* ==========================================================================
   Auth / Default Modal System
   ========================================================================== */
.modal-overlay {
  position: fixed;
  inset: 0;
  background: rgba(15, 23, 42, 0.7);
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 16px;
  opacity: 0;
  visibility: hidden;
  transition: all 0.3s ease;
  z-index: 2000;
  backdrop-filter: blur(5px);
}

.modal-overlay.active { 
  opacity: 1; 
  visibility: visible; 
}

.modal-card {
  background: #ffffff;
  border-radius: var(--radius-lg);
  padding: 32px;
  max-width: 440px;
  width: 100%;
  position: relative;
  box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.25);
}

.modal-close {
  position: absolute;
  top: 16px;
  right: 18px;
  background: none;
  border: none;
  font-size: 1.6rem;
  color: var(--text-muted);
  cursor: pointer;
}

.modal-header h3 { font-size: 1.45rem; font-weight: 800; margin-bottom: 4px; }
.modal-header p { font-size: 0.88rem; color: var(--text-secondary); margin-bottom: 20px; }

.form-group { margin-bottom: 14px; }
.form-group label { display: block; font-size: 0.82rem; font-weight: 700; margin-bottom: 4px; color: var(--text-primary); }
.form-group input {
  width: 100%;
  padding: 10px 14px;
  border-radius: 8px;
  border: 1.5px solid var(--border-color);
  font-size: 0.92rem;
  font-family: inherit;
  outline: none;
  transition: border-color 0.2s;
}

.form-group input:focus { border-color: var(--primary-cyan); }

.form-footer { margin-top: 16px; text-align: center; font-size: 0.85rem; color: var(--text-secondary); }
.form-footer a { color: var(--primary-orange); font-weight: 700; text-decoration: none; }

/* ==========================================================================
   Responsive Breakpoints
   ========================================================================== */
@media (max-width: 1024px) {
  .features-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 20px;
  }

  .hero-section { padding: 50px 0; }
  .hero-subtext { max-width: 100%; }
}

@media (max-width: 992px) {
  .hero-grid-wrap {
    grid-template-columns: 1fr;
    gap: 44px;
  }

  .hero-main-heading {
    font-size: 2.3rem;
  }

  .floating-badge-1 {
    top: -16px;
    right: 0;
  }

  .floating-badge-2 {
    bottom: -16px;
    left: 0;
  }

  .footer-top { grid-template-columns: 1fr; gap: 35px; }
  .footer-contact { align-items: flex-start; text-align: left; }
  .footer-heading::after { left: 0; right: unset; }
  .contact-links { align-items: flex-start; }
  .contact-pill:hover { transform: translateX(6px) scale(1.03); }
}

@media (max-width: 900px) {
  .nav-container {
    gap: 14px;
  }

  .nav-links {
    gap: 18px;
  }

  .nav-links a {
    font-size: 0.96rem;
  }

  .auth-buttons {
    gap: 8px;
  }

  .footer-bottom {
    display: flex;
    flex-direction: column;
    text-align: center;
    justify-content: center;
    gap: 12px;
  }

  .footer-legal-links {
    justify-content: center;
  }

  .developer-credit {
    text-align: center;
  }
}

@media (max-width: 768px) {
  .container {
    padding: 0 18px;
  }

  .nav-container { height: 75px; }
  .nav-logo-img { height: 82px; }
  .footer-logo-img { height: 88px; }

  .hero-main-heading {
    font-size: clamp(1.85rem, 6.5vw, 2.35rem);
    line-height: 1.15;
  }

  .hero-feature-pills {
    gap: 8px;
  }

  .hero-subtext {
    font-size: 0.95rem;
    line-height: 1.55;
  }

  .hero-cta-group {
    flex-direction: column;
    width: 100%;
  }

  .hero-cta-group .btn {
    width: 100%;
  }

  .share-float { bottom: 82px; right: 20px; width: 46px; height: 46px; font-size: 1.25rem; }
  .whatsapp-float { bottom: 20px; right: 20px; width: 52px; height: 52px; font-size: 1.7rem; }

  .modal-overlay {
    padding: 0;
  }

  .doc-modal-card {
    width: 100vw !important;
    max-width: 100vw !important;
    height: 100vh !important;
    height: 100dvh !important;
    max-height: 100dvh !important;
    border-radius: 0 !important;
    border: none !important;
  }

  .doc-modal-header {
    padding: 10px 14px;
  }

  .doc-modal-header h3 {
    font-size: 0.95rem;
  }

  .doc-modal-body {
    padding: 14px 8px;
  }

  .fit-text {
    display: none;
  }

  .nav-links {
    display: none;
    flex-direction: column;
    position: absolute;
    top: 75px;
    left: 0;
    width: 100%;
    background: #ffffff;
    padding: 20px;
    box-shadow: 0 10px 15px rgba(0, 0, 0, 0.05);
    z-index: 1000;
    border-top: 1px solid var(--border-color);
  }

  .nav-links.active { display: flex; }
  .mobile-toggle { display: block; }
}

/* Mobile Navigation Drawer Auth Container */
.mobile-nav-auth {
  display: none;
}

@media (max-width: 768px) {
  .mobile-nav-auth {
    display: flex;
    flex-direction: column;
    gap: 10px;
    width: 100%;
    padding-top: 16px;
    margin-top: 8px;
    border-top: 1px solid var(--border-color);
  }

  .mobile-nav-auth .btn {
    width: 100%;
    padding: 11px 16px;
    font-size: 0.92rem;
    justify-content: center;
  }
}

@media (max-width: 640px) {
  .features-grid {
    grid-template-columns: 1fr;
  }
  .features-main-title {
    font-size: 1.75rem;
  }
  .courses-grid {
    grid-template-columns: 1fr;
  }
  .course-body {
    padding: 18px;
  }
  .course-body h3 {
    font-size: 1.08rem;
  }
  .meta-row,
  .pricing-box {
    flex-wrap: wrap;
    gap: 8px;
  }
  .footer-top {
    gap: 24px;
  }
  .contact-pill {
    width: 100%;
    justify-content: flex-start;
  }
  .copyright-text,
  .developer-credit {
    white-space: normal;
  }
}

@media (max-width: 480px) {
  .container {
    padding: 0 14px;
  }

  .nav-container {
    height: 70px;
    gap: 8px;
  }

  .brand-logo {
    flex: 1;
    min-width: 0;
  }

  .nav-logo-img {
    height: 62px;
    max-width: 220px;
  }

  .auth-buttons {
    gap: 6px;
  }

  .auth-buttons .btn {
    padding: 8px 10px;
    font-size: 0.72rem;
  }

  .feature-card {
    padding: 22px 16px 20px;
  }

  .course-card {
    min-width: 0;
  }

  .course-thumb {
    height: 150px;
  }

  .review-carousel {
    gap: 6px;
  }

  .modal-card {
    padding: 22px 16px;
  }
}

@media (max-width: 390px) {
  .nav-container {
    height: 64px;
  }

  .nav-logo-img {
    height: 54px;
    max-width: 180px;
  }

  .auth-buttons {
    display: none;
  }

  .mobile-toggle {
    margin-left: auto;
  }

  .share-float {
    bottom: 76px;
    right: 14px;
    width: 42px;
    height: 42px;
    font-size: 1.1rem;
  }

  .whatsapp-float {
    bottom: 14px;
    right: 14px;
    width: 48px;
    height: 48px;
    font-size: 1.5rem;
  }

  .hero-cta-group .btn {
    font-size: 0.94rem;
    padding: 12px 16px;
  }
}

@media (max-width: 680px) {
  .reader-toolbar {
    height: auto;
    flex-wrap: wrap;
    padding: 10px 12px;
    justify-content: center;
  }

  .reader-toolbar > div {
    width: 100%;
    justify-content: center;
  }

  .reader-title {
    max-width: 100%;
  }

  .zoom-widget-container {
    display: none;
  }
}

@media (max-width: 420px) {
  .features-main-title,
  .section-header h2 {
    font-size: 1.55rem;
  }

  .badge-recall {
    font-size: 0.7rem;
    letter-spacing: 0.35px;
  }

  .dash-grid {
    grid-template-columns: 1fr;
  }

  .dash-card {
    padding: 18px;
  }

  .expiry-chip {
    white-space: normal;
    line-height: 1.5;
  }

  .action-row .btn {
    font-size: 0.82rem;
  }
}