:root {
  --bg: #060a14;
  --surface: rgba(9, 15, 30, 0.78);
  --surface-strong: rgba(14, 24, 45, 0.9);
  --surface-soft: rgba(255, 255, 255, 0.07);
  --line: rgba(158, 241, 255, 0.22);
  --text: #f7fbff;
  --muted: rgba(224, 240, 255, 0.76);
  --cyan: #18e9ff;
  --blue: #5b8dff;
  --pink: #ff6ad5;
  --green: #5df2a2;
  --yellow: #ffe36e;
  --radius: 8px;
  --shadow: 0 26px 90px rgba(0, 0, 0, 0.52);
}

html[data-theme="light"] {
  --bg: #f5f8ff;
  --surface: rgba(255, 255, 255, 0.82);
  --surface-strong: rgba(255, 255, 255, 0.94);
  --surface-soft: rgba(20, 45, 82, 0.07);
  --line: rgba(58, 92, 140, 0.2);
  --text: #102033;
  --muted: rgba(35, 58, 88, 0.72);
  --cyan: #006fd6;
  --blue: #245bd6;
  --pink: #b22385;
  --green: #087f52;
  --yellow: #8f6400;
  --shadow: 0 18px 50px rgba(55, 81, 120, 0.18);
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  min-height: 100%;
  background: var(--bg);
  scroll-behavior: smooth;
}

body {
  min-height: 100vh;
  margin: 0;
  color: var(--text);
  background:
    linear-gradient(180deg, rgba(5, 7, 19, 0.54), rgba(5, 7, 19, 0.9) 62%, #050713),
    linear-gradient(115deg, rgba(24, 233, 255, 0.16), transparent 36%, rgba(255, 106, 213, 0.12) 72%, rgba(93, 242, 162, 0.08)),
    url("../images/quiz.jpg") center top / cover fixed no-repeat;
  font-family: "Segoe UI", Arial, sans-serif;
  overflow-x: hidden;
}

html[data-theme="light"] body {
  background:
    linear-gradient(180deg, rgba(246, 250, 255, 0.92), rgba(240, 246, 255, 0.84) 62%, #f6faff),
    linear-gradient(115deg, rgba(0, 111, 214, 0.12), transparent 36%, rgba(178, 35, 133, 0.08) 72%, rgba(8, 127, 82, 0.06)),
    url("../images/quiz.jpg") center top / cover fixed no-repeat;
}

body::before {
  content: "";
  position: fixed;
  inset: 0;
  z-index: 0;
  pointer-events: none;
  background:
    linear-gradient(rgba(255, 255, 255, 0.035) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255, 255, 255, 0.035) 1px, transparent 1px),
    linear-gradient(110deg, transparent 0%, rgba(24, 233, 255, 0.1) 48%, rgba(255, 255, 255, 0.12) 52%, transparent 60%);
  background-size: 58px 58px, 58px 58px, 100% 100%;
  opacity: 0.66;
  animation: ambientSweep 18s ease-in-out infinite alternate;
}

html[data-theme="light"] body::before {
  opacity: 0.26;
}

@keyframes ambientSweep {
  from {
    transform: translate3d(-12px, -8px, 0);
  }

  to {
    transform: translate3d(12px, 8px, 0);
  }
}

.landingPage {
  position: relative;
  z-index: 5;
}

.themeToggle {
  position: fixed;
  top: 18px;
  right: 18px;
  z-index: 10;
  display: inline-flex;
  align-items: center;
  gap: 8px;
  min-height: 42px;
  padding: 10px 13px;
  border: 1px solid rgba(158, 241, 255, 0.28);
  border-radius: var(--radius);
  background: rgba(8, 14, 28, 0.72);
  color: var(--text);
  cursor: pointer;
  font: inherit;
  font-size: 0.86rem;
  font-weight: 850;
  letter-spacing: 0;
  backdrop-filter: blur(14px);
  box-shadow: 0 14px 36px rgba(0, 0, 0, 0.24);
  transition: transform 160ms ease, filter 160ms ease, box-shadow 160ms ease;
}

.themeToggle strong {
  color: inherit;
  font-size: 0.78rem;
}

.themeToggle:hover {
  transform: translateY(-2px);
  filter: brightness(1.05);
}

.themeToggle:focus-visible {
  outline: 3px solid rgba(24, 233, 255, 0.62);
  outline-offset: 4px;
}

html[data-theme="light"] .themeToggle {
  border-color: var(--line);
  background: rgba(255, 255, 255, 0.82);
  color: var(--text);
  box-shadow: var(--shadow);
}

.landingHero {
  min-height: 92vh;
  display: grid;
  align-items: center;
  padding: 56px 24px 72px;
}

.landingHeroInner,
.featuresSection,
.ctaSection {
  width: min(1160px, 100%);
  margin: 0 auto;
}

.landingHeroInner {
  display: grid;
  gap: 32px;
}

.login-box {
  max-width: 760px;
  animation: enterCard 520ms ease;
}

@keyframes enterCard {
  from {
    opacity: 0;
    transform: translateY(18px);
  }

  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.login-eyebrow {
  display: inline-flex;
  align-items: center;
  min-height: 28px;
  padding: 5px 10px;
  margin-bottom: 16px;
  border: 1px solid rgba(158, 241, 255, 0.34);
  border-radius: 999px;
  background: linear-gradient(135deg, rgba(24, 233, 255, 0.16), rgba(255, 106, 213, 0.1));
  color: #f2feff;
  font-size: 0.72rem;
  font-weight: 900;
  letter-spacing: 0;
  text-transform: uppercase;
  box-shadow: 0 0 20px rgba(24, 233, 255, 0.2);
}

h1,
h2,
h3,
p {
  letter-spacing: 0;
}

h1 {
  margin: 0;
  color: white;
  font-size: clamp(4rem, 10vw, 8.4rem);
  line-height: 0.92;
  text-shadow:
    0 0 24px rgba(24, 233, 255, 0.44),
    0 0 48px rgba(255, 106, 213, 0.18);
}

.landingTagline {
  margin: 18px 0 0;
  color: #f7fbff;
  font-size: clamp(1.35rem, 3vw, 2.25rem);
  font-weight: 850;
}

.login-copy {
  max-width: 620px;
  margin: 18px 0 0;
  color: var(--muted);
  font-size: 1.05rem;
  font-weight: 650;
  line-height: 1.65;
}

.landingActions {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 28px;
}

.google-login,
.secondaryCta {
  min-height: 52px;
  padding: 13px 18px;
  border-radius: var(--radius);
  cursor: pointer;
  font-size: 1rem;
  font-weight: 850;
  letter-spacing: 0;
  text-decoration: none;
  transition: transform 160ms ease, filter 160ms ease, box-shadow 160ms ease, border-color 160ms ease;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 12px;
}

.google-login {
  border: 1px solid rgba(158, 241, 255, 0.34);
  background:
    linear-gradient(135deg, rgba(255, 255, 255, 0.98), rgba(220, 249, 255, 0.94)),
    var(--surface-soft);
  color: #07111f;
  box-shadow:
    0 0 22px rgba(24, 233, 255, 0.22),
    0 18px 44px rgba(0, 0, 0, 0.42);
}

.secondaryCta {
  border: 1px solid rgba(158, 241, 255, 0.28);
  background: rgba(8, 14, 28, 0.56);
  color: var(--text);
  backdrop-filter: blur(12px);
}

.google-login:hover,
.secondaryCta:hover {
  transform: translateY(-2px);
  filter: brightness(1.05);
  box-shadow:
    0 0 28px rgba(24, 233, 255, 0.24),
    0 22px 52px rgba(0, 0, 0, 0.5);
}

.google-login:active,
.secondaryCta:active {
  transform: translateY(0);
}

.google-login:focus-visible,
.secondaryCta:focus-visible {
  outline: 3px solid rgba(24, 233, 255, 0.62);
  outline-offset: 4px;
}

.google-mark {
  display: grid;
  place-items: center;
  flex: 0 0 auto;
  width: 28px;
  height: 28px;
  border-radius: 50%;
  background: conic-gradient(from -45deg, #4285f4, #34a853, #fbbc05, #ea4335, #4285f4);
  color: white;
  font-weight: 900;
  box-shadow: 0 0 14px rgba(66, 133, 244, 0.32);
}

.login-status {
  max-width: 560px;
  margin: 16px 0 0;
  padding: 10px 12px;
  border: 1px solid rgba(93, 242, 162, 0.3);
  border-radius: var(--radius);
  background: rgba(93, 242, 162, 0.1);
  color: rgba(235, 255, 246, 0.94);
  font-size: 0.9rem;
  font-weight: 750;
}

.login-status--error {
  border-color: rgba(255, 95, 126, 0.34);
  background: rgba(255, 95, 126, 0.1);
  color: #ffe0e6;
}

.heroStats {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 12px;
  width: min(760px, 100%);
}

.heroStats article,
.featureCard,
.ctaSection {
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background:
    linear-gradient(145deg, rgba(255, 255, 255, 0.11), rgba(255, 255, 255, 0.035)),
    var(--surface);
  backdrop-filter: blur(18px) saturate(1.15);
  box-shadow:
    inset 0 1px 0 rgba(255, 255, 255, 0.1),
    var(--shadow);
}

.heroStats article {
  min-height: 104px;
  padding: 18px;
}

.heroStats span {
  display: block;
  color: var(--muted);
  font-size: 0.76rem;
  font-weight: 900;
  text-transform: uppercase;
}

.heroStats strong {
  display: block;
  margin-top: 12px;
  color: white;
  font-size: clamp(1.8rem, 4vw, 2.5rem);
  line-height: 1;
  text-shadow: 0 0 18px rgba(24, 233, 255, 0.34);
}

.featuresSection {
  padding: 36px 24px 26px;
}

.sectionIntro {
  max-width: 720px;
  margin-bottom: 18px;
}

.sectionIntro h2,
.ctaSection h2 {
  margin: 0;
  color: white;
  font-size: clamp(2rem, 4vw, 3.15rem);
  line-height: 1.08;
  text-shadow: 0 0 18px rgba(24, 233, 255, 0.28);
}

.featureGrid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 14px;
}

.featureCard {
  min-height: 236px;
  padding: 22px;
}

.featureIcon {
  display: grid;
  place-items: center;
  width: 42px;
  height: 42px;
  border: 1px solid rgba(158, 241, 255, 0.34);
  border-radius: var(--radius);
  background: linear-gradient(135deg, rgba(24, 233, 255, 0.18), rgba(255, 106, 213, 0.1));
  color: var(--cyan);
  font-size: 1rem;
  font-weight: 950;
}

.featureCard h3 {
  margin: 18px 0 10px;
  color: white;
  font-size: 1.22rem;
  line-height: 1.18;
}

.featureCard p {
  margin: 0;
  color: var(--muted);
  font-size: 0.96rem;
  font-weight: 650;
  line-height: 1.58;
}

.ctaSection {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 18px;
  margin-top: 22px;
  margin-bottom: 56px;
  padding: 24px;
}

.ctaLogin {
  flex: 0 0 auto;
}

html[data-theme="light"] .heroStats article,
html[data-theme="light"] .featureCard,
html[data-theme="light"] .ctaSection {
  background:
    linear-gradient(145deg, rgba(255, 255, 255, 0.96), rgba(246, 250, 255, 0.8)),
    var(--surface);
  color: var(--text);
  box-shadow:
    inset 0 1px 0 rgba(255, 255, 255, 0.82),
    var(--shadow);
}

html[data-theme="light"] h1,
html[data-theme="light"] .landingTagline,
html[data-theme="light"] .sectionIntro h2,
html[data-theme="light"] .ctaSection h2,
html[data-theme="light"] .featureCard h3,
html[data-theme="light"] .heroStats strong {
  color: var(--text);
  text-shadow: none;
}

html[data-theme="light"] .login-copy,
html[data-theme="light"] .featureCard p,
html[data-theme="light"] .heroStats span {
  color: var(--muted);
}

html[data-theme="light"] .login-eyebrow,
html[data-theme="light"] .featureIcon {
  border-color: rgba(0, 111, 214, 0.24);
  background: rgba(0, 111, 214, 0.08);
  color: var(--cyan);
  box-shadow: none;
}

html[data-theme="light"] .secondaryCta {
  border-color: var(--line);
  background: rgba(255, 255, 255, 0.76);
  color: var(--text);
}

#butterfly-container,
#butterfly-gl {
  position: fixed;
  inset: 0;
  z-index: 1;
  overflow: hidden;
  pointer-events: none;
}

.butterfly {
  position: absolute;
  z-index: 2;
  width: 42px;
  height: 42px;
  background-repeat: no-repeat;
  background-size: contain;
  pointer-events: none;
  will-change: transform;
  transform: translate3d(0, 0, 0);
}

.shadow {
  position: absolute;
  z-index: 1;
  width: 35px;
  height: 20px;
  border-radius: 50%;
  background: radial-gradient(ellipse, rgba(0, 0, 0, 0.4), transparent);
  filter: blur(6px);
  pointer-events: none;
  will-change: transform, opacity;
}

.ambient-dot {
  position: fixed;
  left: 0;
  top: 0;
  z-index: 1;
  width: 2px;
  height: 2px;
  border-radius: 50%;
  background: rgba(219, 255, 249, 0.72);
  box-shadow: 0 0 8px rgba(24, 233, 255, 0.7);
  pointer-events: none;
}

@media (max-width: 980px) {
  .landingHero {
    min-height: auto;
    padding-top: 44px;
  }

  .heroStats,
  .featureGrid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .ctaSection {
    align-items: flex-start;
    flex-direction: column;
  }
}

@media (max-width: 620px) {
  .landingHero,
  .featuresSection {
    padding-left: 16px;
    padding-right: 16px;
  }

  .landingHero {
    padding-top: 32px;
    padding-bottom: 44px;
  }

  .landingActions,
  .google-login,
  .secondaryCta,
  .ctaLogin {
    width: 100%;
  }

  .heroStats,
  .featureGrid {
    grid-template-columns: 1fr;
  }

  .featureCard {
    min-height: auto;
  }

  .ctaSection {
    margin-left: 16px;
    margin-right: 16px;
  }
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    scroll-behavior: auto !important;
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}