/* ============================================================
  Teka Ready — style.css
   Modern Aesthetic Landing Page — Total Rework 2026
   ============================================================ */

/* ===== RESET & DESIGN TOKENS ===== */
*, *::before, *::after {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

a[href], button, label[for], select, summary,
input[type="checkbox"], input[type="radio"],
input[type="submit"], input[type="button"] {
  cursor: pointer;
}

:root {
  --primary:        #6366F1;
  --primary-dark:   #4F46E5;
  --primary-light:  #818CF8;
  --secondary:      #8B5CF6;
  --accent:         #06B6D4;
  --accent-warm:    #F59E0B;
  --success:        #10B981;
  --danger:         #EF4444;

  --dark:           #0F172A;
  --dark-2:         #1E293B;
  --gray:           #64748B;
  --light:          #F8FAFC;
  --white:          #FFFFFF;

  --gradient:       linear-gradient(135deg, #6366F1 0%, #8B5CF6 50%, #06B6D4 100%);
  --gradient-warm:  linear-gradient(135deg, #F59E0B, #EF4444);
  --gradient-hero:  linear-gradient(135deg, #0F0C29 0%, #1a1145 40%, #302B63 70%, #24243E 100%);
  --gradient-mesh:  radial-gradient(at 20% 80%, rgba(99,102,241,.3) 0%, transparent 50%),
                    radial-gradient(at 80% 20%, rgba(139,92,246,.25) 0%, transparent 50%),
                    radial-gradient(at 50% 50%, rgba(6,182,212,.15) 0%, transparent 60%);

  --shadow-xs:      0 1px 2px rgba(0,0,0,.05);
  --shadow-sm:      0 1px 3px rgba(0,0,0,.08), 0 1px 2px rgba(0,0,0,.06);
  --shadow-md:      0 4px 6px -1px rgba(0,0,0,.08), 0 2px 4px -2px rgba(0,0,0,.06);
  --shadow-lg:      0 10px 15px -3px rgba(0,0,0,.08), 0 4px 6px -4px rgba(0,0,0,.05);
  --shadow-xl:      0 20px 25px -5px rgba(0,0,0,.1), 0 8px 10px -6px rgba(0,0,0,.06);
  --shadow-glow:    0 0 30px rgba(99,102,241,.12);
  --shadow-glow-lg: 0 0 60px rgba(99,102,241,.15);

  --radius-sm:  8px;
  --radius-md:  12px;
  --radius-lg:  16px;
  --radius-xl:  20px;
  --radius-2xl: 24px;
  --radius-full: 9999px;

  --bg-page:       #FFFFFF;
  --text-main:     #0F172A;
  --text-muted:    #64748B;
  --text-soft:     #94A3B8;
  --surface:       #FFFFFF;
  --surface-soft:  #F8FAFC;
  --surface-alt:   #F1F5F9;
  --border-color:  rgba(148,163,184,.2);
  --border-subtle: rgba(148,163,184,.12);
  --navbar-bg:     rgba(255,255,255,.94);
  --nav-hover-bg:  rgba(99,102,241,.06);
  --footer-bg:     #0F172A;
  --footer-text:   rgba(255,255,255,.65);
  --card-glass:    rgba(255,255,255,.7);
  --card-border:   rgba(148,163,184,.18);
}

[data-theme="dark"] {
  --bg-page:       #080d1a;
  --text-main:     #E2E8F0;
  --text-muted:    #94A3B8;
  --text-soft:     #64748B;
  --surface:       #0f1629;
  --surface-soft:  #111827;
  --surface-alt:   #1E293B;
  --border-color:  rgba(148,163,184,.12);
  --border-subtle: rgba(148,163,184,.08);
  --navbar-bg:     rgba(8,13,26,.96);
  --nav-hover-bg:  rgba(99,102,241,.12);
  --gradient-hero: linear-gradient(135deg, #020617 0%, #0a0f24 40%, #111827 70%, #1E1B4B 100%);
  --footer-bg:     #020617;
  --footer-text:   rgba(226,232,240,.72);
  --card-glass:    rgba(15,22,41,.65);
  --card-border:   rgba(148,163,184,.1);
}

html { scroll-behavior: smooth; }

body {
  font-family: 'Inter', 'Poppins', system-ui, -apple-system, sans-serif;
  background: var(--bg-page);
  color: var(--text-main);
  line-height: 1.65;
  overflow-x: hidden;
  transition: background-color .3s ease, color .3s ease;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

.container {
  width: 90%;
  max-width: 1200px;
  margin: 0 auto;
}

/* ===== ANIMATIONS ===== */
@keyframes float {
  0%, 100% { transform: translateY(0) rotate(0deg); }
  33% { transform: translateY(-12px) rotate(1deg); }
  66% { transform: translateY(6px) rotate(-1deg); }
}

@keyframes pulse-glow {
  0%, 100% { opacity: .2; transform: scale(1); }
  50% { opacity: .35; transform: scale(1.05); }
}

@keyframes gradient-shift {
  0% { background-position: 0% 50%; }
  50% { background-position: 100% 50%; }
  100% { background-position: 0% 50%; }
}

@keyframes fade-up {
  from { opacity: 0; transform: translateY(30px); }
  to { opacity: 1; transform: translateY(0); }
}

@keyframes shimmer {
  0% { background-position: -200% center; }
  100% { background-position: 200% center; }
}

@keyframes border-dance {
  0%, 100% { border-color: rgba(99,102,241,.2); }
  50% { border-color: rgba(139,92,246,.35); }
}

/* ===== BUTTONS ===== */
.btn-primary {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  text-decoration: none;
  background: var(--gradient);
  background-size: 200% 200%;
  color: white;
  border: none;
  padding: 12px 24px;
  border-radius: var(--radius-md);
  font-family: inherit;
  font-weight: 600;
  font-size: .9rem;
  letter-spacing: -.01em;
  cursor: pointer;
  transition: all .3s cubic-bezier(.4,0,.2,1);
  box-shadow: 0 4px 15px rgba(99,102,241,.3), 0 1px 3px rgba(0,0,0,.1);
  position: relative;
  overflow: hidden;
}

.btn-primary::after {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, rgba(255,255,255,.2), transparent);
  opacity: 0;
  transition: opacity .3s ease;
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 25px rgba(99,102,241,.4), 0 2px 6px rgba(0,0,0,.12);
  background-position: 100% 50%;
}

.btn-primary:hover::after { opacity: 1; }
.btn-primary:active { transform: translateY(0); }

.btn-primary.btn-lg {
  padding: 16px 36px;
  font-size: 1rem;
  border-radius: var(--radius-lg);
}

.btn-outline {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  text-decoration: none;
  background: rgba(255,255,255,.08);
  color: white;
  border: 1.5px solid rgba(255,255,255,.25);
  padding: 14px 32px;
  border-radius: var(--radius-lg);
  font-family: inherit;
  font-weight: 600;
  font-size: 1rem;
  cursor: pointer;
  transition: all .3s ease;
  backdrop-filter: blur(8px);
}

.btn-outline:hover {
  background: rgba(255,255,255,.15);
  border-color: rgba(255,255,255,.5);
  transform: translateY(-2px);
}

.btn-ghost {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  text-decoration: none;
  background: transparent;
  color: var(--text-main);
  border: none;
  padding: 10px 18px;
  border-radius: var(--radius-sm);
  font-family: inherit;
  font-weight: 500;
  font-size: .9rem;
  cursor: pointer;
  transition: all .25s ease;
}

.btn-ghost:hover {
  background: var(--surface-alt);
  color: var(--primary);
}

/* ===== NAVBAR ===== */
.navbar {
  position: sticky;
  top: 14px;
  z-index: 100;
  transition: box-shadow .3s ease, background .3s ease, transform .3s ease;
}

.navbar.scrolled {
  transform: translateY(-2px);
}

.nav-container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 14px 18px;
  position: relative;
  isolation: isolate;
  overflow: hidden;
  background: var(--navbar-bg);
  backdrop-filter: blur(18px) saturate(1.35);
  -webkit-backdrop-filter: blur(18px) saturate(1.35);
  border: 1px solid var(--border-subtle);
  border-radius: 22px;
  box-shadow: 0 16px 40px rgba(15,23,42,.08), inset 0 1px 0 rgba(255,255,255,.24);
}

.nav-container::before {
  content: '';
  position: absolute;
  inset: 0;
  border-radius: inherit;
  background: linear-gradient(180deg, rgba(255,255,255,.12), rgba(255,255,255,0));
  pointer-events: none;
  z-index: 0;
}

.nav-container > * {
  position: relative;
  z-index: 1;
}

.nav-brand {
  display: flex;
  align-items: center;
  min-width: 0;
}

.logo {
  color: var(--text-main);
  display: flex;
  align-items: center;
  gap: 10px;
  text-decoration: none;
  user-select: none;
  letter-spacing: -.02em;
}

.logo-mark {
  width: 34px;
  height: 34px;
  display: block;
  flex-shrink: 0;
}

.logo-copy {
  display: flex;
  flex-direction: column;
  gap: 2px;
  min-width: 0;
}

.logo-label {
  font-size: 1.18rem;
  font-weight: 800;
  line-height: 1;
}

.logo-tagline {
  font-size: .7rem;
  line-height: 1.2;
  color: var(--text-soft);
  letter-spacing: .06em;
  text-transform: uppercase;
}

.logo-accent {
  background: var(--gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.nav-links {
  display: flex;
  list-style: none;
  gap: 6px;
  padding: 6px;
  background: rgba(255,255,255,.82);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-full);
  box-shadow: inset 0 1px 0 rgba(255,255,255,.35);
}

.nav-links a {
  text-decoration: none;
  color: var(--text-muted);
  font-size: .82rem;
  font-weight: 700;
  padding: 10px 14px;
  border-radius: var(--radius-full);
  transition: all .25s ease, box-shadow .25s ease;
  position: relative;
  letter-spacing: .01em;
}

.nav-links a:hover {
  color: var(--primary);
  background: rgba(255,255,255,.92);
  box-shadow: 0 8px 18px rgba(99,102,241,.12);
}

.nav-links a::after {
  content: '';
  position: absolute;
  bottom: 6px;
  left: 50%;
  width: 0;
  height: 2px;
  background: var(--gradient);
  border-radius: 1px;
  transition: all .3s cubic-bezier(.4,0,.2,1);
  transform: translateX(-50%);
}

.nav-links a:hover::after {
  width: 60%;
}

.nav-actions {
  display: flex;
  align-items: center;
  gap: 10px;
  padding-left: 12px;
}

.mobile-auth { display: none; }
.nav-actions .switch { order: 3; }
.nav-actions .btn-ghost { order: 1; }
.nav-actions .btn-primary { order: 2; }

.nav-login-link {
  color: var(--text-main);
  font-weight: 700;
  border-radius: var(--radius-full);
  padding: 10px 14px;
}

.menu-toggle {
  display: none;
  background: rgba(255,255,255,.7);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-full);
  padding: 8px 14px;
  font-size: .84rem;
  font-weight: 700;
  cursor: pointer;
  color: var(--text-main);
  z-index: 120;
  transition: transform .3s ease, border-color .2s ease, background-color .2s ease;
}

[data-theme="dark"] .nav-container {
  background: rgba(8,13,26,.96);
  box-shadow: 0 18px 44px rgba(2,6,23,.42), inset 0 1px 0 rgba(255,255,255,.04);
}

[data-theme="dark"] .nav-container::before {
  background: linear-gradient(180deg, rgba(255,255,255,.03), rgba(255,255,255,0));
}

[data-theme="dark"] .nav-links {
  background: rgba(15,23,42,.92);
  border-color: rgba(148,163,184,.1);
  box-shadow: inset 0 1px 0 rgba(255,255,255,.03);
}

[data-theme="dark"] .nav-links a:hover {
  background: rgba(30,41,59,.95);
  box-shadow: 0 10px 22px rgba(2,6,23,.4);
}

[data-theme="dark"] .menu-toggle {
  background: rgba(15,23,42,.78);
}

/* ===== THEME TOGGLE ===== */
.switch {
  font-size: 17px;
  position: relative;
  display: inline-block;
  width: 4em;
  height: 2.2em;
  border-radius: 30px;
  box-shadow: 0 0 10px rgba(0, 0, 0, 0.1);
}
.switch input {
  opacity: 0;
  width: 0;
  height: 0;
}
.slider {
  position: absolute;
  cursor: pointer;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background-color: #2a2a2a;
  transition: 0.4s;
  border-radius: 30px;
  overflow: hidden;
}
.slider:before {
  position: absolute;
  content: "";
  height: 1.2em;
  width: 1.2em;
  border-radius: 20px;
  left: 0.5em;
  bottom: 0.5em;
  transition: 0.4s;
  transition-timing-function: cubic-bezier(0.81, -0.04, 0.38, 1.5);
  box-shadow: inset 8px -4px 0px 0px #fff;
}
.switch input:checked + .slider {
  background-color: #00a6ff;
}
.switch input:checked + .slider:before {
  transform: translateX(1.8em);
  box-shadow: inset 15px -4px 0px 15px #ffcf48;
}
.star {
  background-color: #fff;
  border-radius: 50%;
  position: absolute;
  width: 5px;
  transition: all 0.4s;
  height: 5px;
}
.star_1 { left: 2.5em; top: 0.5em; }
.star_2 { left: 2.2em; top: 1.2em; }
.star_3 { left: 3em;   top: 0.9em; }
.switch input:checked ~ .slider .star { opacity: 0; }
.cloud {
  width: 3.5em;
  position: absolute;
  bottom: -1.4em;
  left: -1.1em;
  opacity: 0;
  transition: all 0.4s;
}
.switch input:checked ~ .slider .cloud { opacity: 1; }



/* Dark mode icon backgrounds */
[data-theme="dark"] .icon-indigo { background: rgba(99,102,241,.15); }
[data-theme="dark"] .icon-orange { background: rgba(249,115,22,.12); }
[data-theme="dark"] .icon-green  { background: rgba(16,185,129,.12); }
[data-theme="dark"] .icon-purple { background: rgba(139,92,246,.15); }
[data-theme="dark"] .icon-red    { background: rgba(239,68,68,.12); }
[data-theme="dark"] .icon-cyan   { background: rgba(6,182,212,.12); }

/* ===== HERO ===== */
.hero {
  position: relative;
  background: var(--gradient-hero);
  color: white;
  padding: 120px 0 168px;
  overflow: hidden;
  text-align: center;
}

.hero::before {
  content: '';
  position: absolute;
  inset: 0;
  background: var(--gradient-mesh);
  opacity: .6;
  pointer-events: none;
}

.hero::after {
  content: '';
  position: absolute;
  left: 0;
  right: 0;
  bottom: -1px;
  height: 120px;
  background: linear-gradient(180deg, rgba(255,255,255,0) 0%, rgba(248,250,252,.85) 100%);
  pointer-events: none;
}

.hero-bg-shapes { position: absolute; inset: 0; pointer-events: none; }

.shape {
  position: absolute;
  border-radius: 50%;
  filter: blur(100px);
}

.shape-1 {
  width: 600px; height: 600px;
  background: rgba(99,102,241,.35);
  top: -200px; left: -150px;
  animation: pulse-glow 8s ease-in-out infinite;
}

.shape-2 {
  width: 500px; height: 500px;
  background: rgba(139,92,246,.3);
  bottom: -150px; right: -120px;
  animation: pulse-glow 10s ease-in-out infinite 2s;
}

.shape-3 {
  width: 350px; height: 350px;
  background: rgba(6,182,212,.2);
  top: 40%; left: 50%;
  transform: translate(-50%, -50%);
  animation: pulse-glow 12s ease-in-out infinite 4s;
}

.hero-inner { position: relative; z-index: 1; }

.hero-badge {
  display: inline-flex;
  align-items: center;
  background: rgba(99,102,241,.2);
  border: 1px solid rgba(99,102,241,.3);
  color: #C7D2FE;
  font-size: .8rem;
  font-weight: 600;
  padding: 8px 20px;
  border-radius: var(--radius-full);
  margin-bottom: 32px;
  letter-spacing: .3px;
  backdrop-filter: blur(8px);
  animation: fade-up .8s ease-out;
}

.hero-title {
  font-size: clamp(2.5rem, 6.5vw, 4.2rem);
  font-weight: 800;
  line-height: 1.12;
  margin-bottom: 22px;
  letter-spacing: -.03em;
  animation: fade-up .8s ease-out .1s both;
}

.gradient-text {
  background: linear-gradient(90deg, #A5B4FC, #C084FC, #67E8F9, #FCD34D);
  background-size: 300% 100%;
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  animation: gradient-shift 6s ease infinite;
}

.hero-subtitle {
  font-size: 1.08rem;
  color: rgba(255,255,255,.65);
  max-width: 600px;
  margin: 0 auto 42px;
  line-height: 1.8;
  animation: fade-up .8s ease-out .2s both;
}

.hero-cta {
  display: flex;
  gap: 16px;
  justify-content: center;
  flex-wrap: wrap;
  margin-bottom: 64px;
  animation: fade-up .8s ease-out .3s both;
}

.hero-stats {
  display: inline-flex;
  align-items: center;
  gap: 40px;
  background: rgba(255,255,255,.06);
  border: 1px solid rgba(255,255,255,.1);
  padding: 24px 48px;
  border-radius: var(--radius-xl);
  backdrop-filter: blur(16px);
  flex-wrap: wrap;
  justify-content: center;
  animation: fade-up .8s ease-out .4s both;
}

.stat-item { display: flex; flex-direction: column; align-items: center; }

.stat-item strong {
  font-size: 1.8rem;
  font-weight: 800;
  color: white;
  line-height: 1;
  letter-spacing: -.02em;
}

.stat-item span {
  font-size: .78rem;
  color: rgba(255,255,255,.5);
  margin-top: 6px;
  font-weight: 500;
}

.stat-divider {
  width: 1px;
  height: 40px;
  background: linear-gradient(180deg, transparent, rgba(255,255,255,.2), transparent);
}

/* ===== SECTION COMMON ===== */
.section-label {
  display: inline-block;
  color: var(--primary);
  font-size: .72rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 3px;
  margin-bottom: 12px;
  position: relative;
}

.section-title {
  font-size: clamp(1.6rem, 3.2vw, 2.2rem);
  font-weight: 700;
  color: var(--text-main);
  margin-bottom: 52px;
  line-height: 1.25;
  letter-spacing: -.02em;
}

/* ===== FEATURES ===== */
.features {
  padding: 72px 0 100px;
  background: var(--surface-soft);
  position: relative;
  margin-top: 0;
  z-index: 2;
}

.features::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 1px;
  background: linear-gradient(90deg, transparent, var(--border-color), transparent);
}

.features .container {
  text-align: center;
  position: relative;
  z-index: 1;
}

.features .section-title {
  max-width: 760px;
  margin-left: auto;
  margin-right: auto;
}

[data-theme="dark"] .hero::after {
  background: linear-gradient(180deg, rgba(8,13,26,0) 0%, rgba(15,22,41,.88) 100%);
}

[data-theme="dark"] .features::after {
  display: none;
}

.feature-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
  text-align: left;
  margin-top: 0;
}

.feature-card {
  background: var(--card-glass);
  border: 1px solid var(--card-border);
  border-radius: var(--radius-xl);
  padding: 32px 28px;
  backdrop-filter: blur(10px);
  transition: all .35s cubic-bezier(.4,0,.2,1);
  position: relative;
  overflow: hidden;
}

.feature-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: var(--gradient);
  opacity: 0;
  transition: opacity .35s ease;
}

.feature-card:hover {
  border-color: rgba(99,102,241,.25);
  box-shadow: var(--shadow-lg), var(--shadow-glow);
  transform: translateY(-6px);
}

.feature-card:hover::before { opacity: 1; }

.feature-icon {
  width: 56px;
  height: 56px;
  border-radius: var(--radius-lg);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 18px;
  transition: transform .3s ease;
}

.feature-icon-image {
  width: 32px;
  height: 32px;
  display: block;
}

.feature-card:hover .feature-icon { transform: scale(1.1); }

.icon-indigo { background: linear-gradient(135deg, #EEF2FF, #E0E7FF); }
.icon-orange { background: linear-gradient(135deg, #FFF7ED, #FFEDD5); }
.icon-green  { background: linear-gradient(135deg, #ECFDF5, #D1FAE5); }
.icon-purple { background: linear-gradient(135deg, #FAF5FF, #F3E8FF); }
.icon-red    { background: linear-gradient(135deg, #FFF1F2, #FFE4E6); }
.icon-cyan   { background: linear-gradient(135deg, #ECFEFF, #CFFAFE); }

.feature-card h3 {
  font-size: .95rem;
  font-weight: 700;
  color: var(--text-main);
  margin-bottom: 10px;
  letter-spacing: -.01em;
}

.feature-card p {
  font-size: .855rem;
  color: var(--text-muted);
  line-height: 1.7;
}

/* ===== HOW IT WORKS ===== */
.how-it-works {
  padding: 100px 0;
  background: var(--bg-page);
}

.how-it-works .container { text-align: center; }

.steps-grid {
  display: flex;
  align-items: center;
  gap: 12px;
  justify-content: center;
  flex-wrap: wrap;
}

.step-card {
  background: var(--card-glass);
  border: 1px solid var(--card-border);
  border-radius: var(--radius-xl);
  padding: 32px 24px;
  flex: 1;
  min-width: 170px;
  max-width: 220px;
  text-align: center;
  transition: all .35s ease;
  backdrop-filter: blur(8px);
}

.step-card:hover {
  background: var(--nav-hover-bg);
  transform: translateY(-5px);
  box-shadow: var(--shadow-md);
}

.step-number {
  font-size: 2.4rem;
  font-weight: 800;
  line-height: 1;
  margin-bottom: 16px;
  letter-spacing: -.04em;
  background: var(--gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.step-card h3 {
  font-size: .95rem;
  font-weight: 700;
  margin-bottom: 8px;
}

.step-card p {
  font-size: .82rem;
  color: var(--text-muted);
  line-height: 1.65;
}

.step-arrow {
  width: 56px;
  height: 14px;
  position: relative;
  flex: 0 0 56px;
  opacity: .9;
}

.step-arrow::before {
  content: '';
  position: absolute;
  top: 50%;
  left: 0;
  right: 10px;
  height: 2px;
  background: linear-gradient(90deg, rgba(148,163,184,.25), rgba(99,102,241,.55));
  transform: translateY(-50%);
}

.step-arrow::after {
  content: '';
  position: absolute;
  top: 50%;
  right: 0;
  width: 8px;
  height: 8px;
  border-top: 2px solid rgba(99,102,241,.7);
  border-right: 2px solid rgba(99,102,241,.7);
  transform: translateY(-50%) rotate(45deg);
}

/* ===== MATA PELAJARAN ===== */
.subjects {
  padding: 100px 0;
  background: var(--surface-soft);
  position: relative;
}

.subjects::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 1px;
  background: linear-gradient(90deg, transparent, var(--border-color), transparent);
}

.subjects .container { text-align: center; }

.subject-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 24px;
  text-align: left;
}

.subject-card {
  border-radius: var(--radius-2xl);
  padding: 40px;
  position: relative;
  overflow: hidden;
  transition: all .35s ease;
}

.subject-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-xl);
}

.subject-math {
  background: linear-gradient(135deg, #EEF2FF 0%, #E0E7FF 50%, #C7D2FE 100%);
  border: 1px solid rgba(99,102,241,.2);
}

.subject-indo {
  background: linear-gradient(135deg, #FFF7ED 0%, #FFEDD5 50%, #FED7AA 100%);
  border: 1px solid rgba(249,115,22,.2);
}

[data-theme="dark"] .subject-math {
  background: linear-gradient(135deg, rgba(99,102,241,.1) 0%, rgba(99,102,241,.05) 100%);
  border-color: rgba(99,102,241,.2);
}

[data-theme="dark"] .subject-indo {
  background: linear-gradient(135deg, rgba(249,115,22,.1) 0%, rgba(249,115,22,.05) 100%);
  border-color: rgba(249,115,22,.2);
}

.subject-emoji { display: inline-flex; margin-bottom: 16px; }

.subject-mark {
  width: 92px;
  height: 72px;
  justify-content: center;
  align-items: center;
  padding: 10px 12px;
  border-radius: 18px;
  background: rgba(15,23,42,.78);
  border: 1px solid rgba(255,255,255,.08);
  box-shadow: var(--shadow-sm);
}

.subject-mark-image {
  width: 42px;
  height: 42px;
  display: block;
}

[data-theme="dark"] .subject-mark {
  background: rgba(15,23,42,.82);
  border-color: rgba(255,255,255,.08);
}
.subject-card h3 { font-size: 1.4rem; font-weight: 700; margin-bottom: 12px; }
.subject-math h3 { color: #4338CA; }
.subject-indo h3 { color: #C2410C; }

[data-theme="dark"] .subject-math h3 { color: #A5B4FC; }
[data-theme="dark"] .subject-indo h3 { color: #FDBA74; }

.subject-card > p {
  font-size: .88rem;
  color: var(--text-muted);
  margin-bottom: 22px;
  line-height: 1.75;
}

.subject-topics { list-style: none; margin-bottom: 28px; }

.subject-topics li {
  font-size: .855rem;
  color: var(--text-main);
  padding: 8px 0;
  border-bottom: 1px dashed var(--border-color);
  display: flex;
  align-items: center;
  gap: 10px;
}

.subject-topics li::before { content: "✓"; font-weight: 800; font-size: .9rem; }
.subject-math .subject-topics li::before { color: #6366F1; }
.subject-indo .subject-topics li::before { color: #F97316; }

.btn-subject {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  text-decoration: none;
  padding: 12px 28px;
  border-radius: var(--radius-md);
  font-family: inherit;
  font-weight: 600;
  font-size: .88rem;
  cursor: pointer;
  border: none;
  transition: all .3s ease;
  position: relative;
  overflow: hidden;
}

.btn-subject:hover { transform: translateY(-2px); }

.subject-math .btn-subject {
  background: linear-gradient(135deg, #6366F1, #818CF8);
  color: white;
  box-shadow: 0 4px 15px rgba(99,102,241,.3);
}

.subject-indo .btn-subject {
  background: linear-gradient(135deg, #F97316, #FB923C);
  color: white;
  box-shadow: 0 4px 15px rgba(249,115,22,.3);
}

/* ===== TESTIMONIALS ===== */
.testimonials {
  padding: 100px 0;
  background: var(--bg-page);
}

.testimonials .container { text-align: center; }

.testi-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
  text-align: left;
}

.testi-card {
  background: var(--card-glass);
  border: 1px solid var(--card-border);
  border-radius: var(--radius-xl);
  padding: 30px;
  transition: all .35s ease;
  backdrop-filter: blur(8px);
  position: relative;
}

.testi-card::before {
  content: '"';
  position: absolute;
  top: 16px;
  right: 24px;
  font-size: 4rem;
  font-weight: 800;
  line-height: 1;
  background: var(--gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  opacity: .15;
}

.testi-card:hover {
  box-shadow: var(--shadow-lg);
  transform: translateY(-4px);
  border-color: rgba(99,102,241,.2);
}

.testi-stars {
  color: #F59E0B;
  font-size: .9rem;
  letter-spacing: 3px;
  margin-bottom: 16px;
}

.testi-card p {
  font-size: .87rem;
  color: var(--text-main);
  line-height: 1.8;
  margin-bottom: 22px;
  font-style: italic;
}

.testi-author { display: flex; align-items: center; gap: 12px; }

.testi-avatar {
  width: 42px;
  height: 42px;
  border-radius: 50%;
  background: var(--gradient);
  color: white;
  font-weight: 700;
  font-size: .9rem;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  box-shadow: 0 4px 12px rgba(99,102,241,.25);
}

.testi-author strong {
  display: block;
  font-size: .88rem;
  color: var(--text-main);
}

.testi-author span {
  font-size: .76rem;
  color: var(--text-muted);
}

/* ===== FAQ ===== */
.faq-section {
  padding: 100px 0 30px;
  background:
    radial-gradient(circle at top left, rgba(99,102,241,.08), transparent 35%),
    radial-gradient(circle at bottom right, rgba(6,182,212,.08), transparent 40%);
}

.faq-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 20px;
  margin-top: 42px;
}

.faq-card {
  background: var(--card-glass);
  border: 1px solid var(--card-border);
  border-radius: var(--radius-xl);
  padding: 28px 24px;
  box-shadow: var(--shadow-md);
}

.faq-card h3 {
  font-size: 1rem;
  font-weight: 700;
  margin-bottom: 10px;
  letter-spacing: -.02em;
}

.faq-card p {
  color: var(--text-muted);
  font-size: .88rem;
  line-height: 1.75;
}

/* ===== CTA SECTION ===== */
.cta-section {
  padding: 80px 0;
  background: var(--surface-soft);
}

.cta-box {
  background: linear-gradient(135deg, #6366F1 0%, #8B5CF6 40%, #06B6D4 100%);
  background-size: 200% 200%;
  animation: gradient-shift 8s ease infinite;
  border-radius: var(--radius-2xl);
  padding: 80px 60px;
  text-align: center;
  position: relative;
  overflow: hidden;
}

.cta-shape {
  position: absolute;
  border-radius: 50%;
  background: rgba(255,255,255,.06);
  pointer-events: none;
}

.cta-shape-1 {
  width: 350px;
  height: 350px;
  top: -120px;
  left: -100px;
  animation: float 10s ease-in-out infinite;
}

.cta-shape-2 {
  width: 250px;
  height: 250px;
  bottom: -80px;
  right: -60px;
  animation: float 12s ease-in-out infinite 3s;
}

.cta-content { position: relative; z-index: 1; }

.cta-box h2 {
  font-size: clamp(1.6rem, 3.2vw, 2.2rem);
  font-weight: 700;
  color: white;
  margin-bottom: 16px;
  letter-spacing: -.02em;
}

.cta-box p {
  color: rgba(255,255,255,.78);
  font-size: 1.05rem;
  margin-bottom: 36px;
}

.cta-white-btn {
  background: white !important;
  color: var(--primary) !important;
  box-shadow: 0 8px 30px rgba(0,0,0,.2) !important;
}

.cta-white-btn:hover {
  transform: translateY(-3px) !important;
  box-shadow: 0 14px 40px rgba(0,0,0,.25) !important;
}

/* ===== FOOTER ===== */
.footer {
  background: var(--footer-bg);
  color: var(--footer-text);
  position: relative;
}

.footer::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 1px;
  background: linear-gradient(90deg, transparent, rgba(99,102,241,.3), transparent);
}

.footer-inner {
  display: grid;
  grid-template-columns: 2fr 3fr;
  gap: 60px;
  padding: 64px 0 48px;
}

.footer-brand .logo { color: white; margin-bottom: 16px; }

.footer-brand p {
  font-size: .84rem;
  line-height: 1.75;
  max-width: 260px;
  color: var(--footer-text);
}

.footer-links { display: flex; gap: 52px; justify-content: flex-end; }

.footer-col h4 {
  color: white;
  font-size: .85rem;
  font-weight: 700;
  margin-bottom: 18px;
  letter-spacing: -.01em;
}

.footer-col ul {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.footer-col a {
  text-decoration: none;
  color: rgba(255,255,255,.45);
  font-size: .84rem;
  transition: all .25s ease;
}

.footer-col a:hover {
  color: white;
  padding-left: 4px;
}

.footer-bottom {
  border-top: 1px solid rgba(255,255,255,.08);
  padding: 22px 0;
  text-align: center;
}

.footer-bottom p {
  font-size: .8rem;
  color: rgba(255,255,255,.3);
}

/* ===== SCROLL REVEAL ===== */
.reveal {
  opacity: 0;
  transform: translateY(28px);
  transition: opacity .6s cubic-bezier(.4,0,.2,1), transform .6s cubic-bezier(.4,0,.2,1);
}

.reveal.visible {
  opacity: 1;
  transform: translateY(0);
}

/* ===== RESPONSIVE ===== */
@media (max-width: 960px) {
  .navbar {
    top: 10px;
  }

  .nav-container {
    padding: 12px 14px;
    border-radius: 20px;
  }

  .nav-links {
    gap: 2px;
    padding: 4px;
  }

  .nav-links a {
    padding: 10px 12px;
    font-size: .79rem;
  }

  .nav-actions {
    gap: 8px;
    padding-left: 8px;
  }

  .nav-login-link,
  .nav-actions .btn-primary {
    padding-inline: 12px;
  }

  .feature-grid    { grid-template-columns: 1fr 1fr; }
  .faq-grid        { grid-template-columns: 1fr 1fr; }
  .subject-grid    { grid-template-columns: 1fr; }
  .testi-grid      { grid-template-columns: 1fr 1fr; }
  .footer-inner    { grid-template-columns: 1fr; gap: 36px; }
  .footer-links    { justify-content: flex-start; }
}

@media (max-width: 660px) {
  .navbar {
    top: 8px;
  }

  .nav-container {
    padding: 12px;
    border-radius: 18px;
    overflow: visible;
  }

  .logo {
    gap: 10px;
  }

  .logo-mark {
    width: 42px;
    height: 42px;
  }

  .logo-label {
    font-size: 1.02rem;
  }

  .logo-tagline {
    font-size: .62rem;
  }

  .site-nav {
    position: absolute;
    top: calc(100% + 10px);
    left: 0;
    right: 0;
    display: block;
    max-height: 0;
    opacity: 0;
    transform: translateY(-10px) scale(.98);
    pointer-events: none;
    overflow: hidden;
    z-index: 110;
    transition: max-height .35s ease, opacity .25s ease, transform .35s ease;
  }

  .navbar.menu-open .site-nav {
    max-height: 520px;
    opacity: 1;
    transform: translateY(0) scale(1);
    pointer-events: auto;
  }

  .nav-links {
    display: flex;
    flex-direction: column;
    gap: 8px;
    background: color-mix(in srgb, var(--surface) 92%, transparent);
    border: 1px solid var(--card-border);
    border-radius: 24px;
    padding: 14px;
    box-shadow: 0 20px 50px rgba(15,23,42,.14), inset 0 1px 0 rgba(255,255,255,.24);
  }

  .nav-links li {
    opacity: 0;
    transform: translateY(-6px);
    transition: opacity .22s ease, transform .22s ease;
  }

  .navbar.menu-open .nav-links li {
    opacity: 1;
    transform: translateY(0);
  }

  .navbar.menu-open .nav-links li:nth-child(1) { transition-delay: .04s; }
  .navbar.menu-open .nav-links li:nth-child(2) { transition-delay: .08s; }
  .navbar.menu-open .nav-links li:nth-child(3) { transition-delay: .12s; }
  .navbar.menu-open .nav-links li:nth-child(4) { transition-delay: .16s; }
  .navbar.menu-open .nav-links li:nth-child(5) { transition-delay: .20s; }
  .navbar.menu-open .nav-links li:nth-child(6) { transition-delay: .24s; }

  .nav-links a {
    display: block;
    padding: 13px 14px;
    border-radius: 16px;
    background: rgba(255,255,255,.72);
    color: var(--text-main);
  }

  .nav-links a::after {
    display: none;
  }

  .mobile-auth a {
    background: rgba(255,255,255,.86);
  }

  .mobile-auth { display: block; }
  .mobile-auth a { font-weight: 600; }
  .nav-actions .switch { order: 1; }
  .nav-links, .nav-actions .btn-ghost, .nav-actions .btn-primary { display: none; }
  .navbar.menu-open .nav-links { display: flex; }
  .navbar.menu-open .menu-toggle { transform: none; }
  .nav-actions {
    display: flex;
    margin-left: auto;
    margin-right: 8px;
    padding-left: 0;
    gap: 8px;
  }
  .switch { font-size: 15px; }
  .menu-toggle { display: block; }

  [data-theme="dark"] .nav-links {
    background: rgba(8,13,26,.94);
    box-shadow: 0 20px 50px rgba(2,6,23,.5), inset 0 1px 0 rgba(255,255,255,.04);
  }

  [data-theme="dark"] .nav-links a,
  [data-theme="dark"] .mobile-auth a {
    background: rgba(15,23,42,.88);
    color: var(--text-main);
  }

  .feature-grid  { grid-template-columns: 1fr; }
  .faq-grid      { grid-template-columns: 1fr; }
  .testi-grid    { grid-template-columns: 1fr; }
  .steps-grid    { flex-direction: column; align-items: stretch; }
  .step-arrow    { transform: rotate(90deg); }
  .step-card     { max-width: 100%; }
  .cta-box       { padding: 52px 28px; border-radius: var(--radius-xl); }
  .hero-stats    { gap: 20px; padding: 18px 24px; }
  .footer-links  { flex-wrap: wrap; gap: 32px; }

  .hero {
    padding: 90px 0 128px;
  }

  .hero::after {
    height: 88px;
  }

  .features {
    margin-top: 0;
    padding-top: 64px;
  }

  .hero-title { font-size: clamp(2rem, 8vw, 3rem); }
}