:root {
  --bg-gradient-start: #1A237E;
  --bg-gradient-end:   #FFF8E1;
  --overlay-color:     rgba(255, 255, 255, 0.15);
  --star-opacity:      0.4;
  --text-color:        #E8EAF6;
  --accent-color:      #FFF176;
  --heading-letter-spacing: 2px;
  --body-font:         'Open Sans', sans-serif;
  --heading-font:      'Orbitron', sans-serif;
}

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

body {
  font-family: var(--body-font);
  font-weight: 300;
  line-height: 1.6;
  color: var(--text-color);
  background: #1a1d1f;
  position: relative;
  overflow: hidden;
  padding: 2rem;
  height: 100vh;
  display: flex;
  flex-direction: column;
}

body::before {
  content: '';
  position: fixed;
  top: 0;
  left: 0;
  width: 100vw;
  height: 100vh;
  background: url('#') repeat;
  opacity: var(--star-opacity);
  animation: drift 60s linear infinite;
  pointer-events: none;
}


h1 {
  font-family: 'Orbitron', sans-serif;
  font-weight: 400;
  font-size: clamp(2.5rem, 6vw, 4rem);
  color: #FFEB3B;
  text-align: center;
  margin-bottom: 2rem;
  letter-spacing: 3px;
  text-shadow: 
    0 0 10px rgba(255, 235, 59, 0.5),
    0 0 20px rgba(255, 235, 59, 0.3),
    0 0 30px rgba(255, 235, 59, 0.2);
  position: relative;
}

h1::after {
  content: '';
  position: absolute;
  bottom: -8px;
  left: 50%;
  transform: translateX(-50%);
  width: 100px;
  height: 2px;
  background: linear-gradient(90deg, transparent, #FFEB3B, transparent);
  opacity: 0.6;
}

h2, h3, h4 {
  font-family: var(--heading-font);
  font-weight: 700;
  letter-spacing: var(--heading-letter-spacing);
  color: #7986CB;
  margin-bottom: 1rem;
  text-align: center;
}

main {
  flex: 1;
  overflow-y: auto;
  background: radial-gradient(circle at center,
    #FFECB3,
    #3F51B5,
    #1A237E);
  border-radius: 8px;
  margin: 0 -1rem;
  padding: 0 1rem;
}



.neon-list {
  max-width: 800px;
  margin: 2rem auto;
  background: var(--overlay-color);
  padding: 1.5rem;
  border-radius: 8px;
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.5);
  counter-reset: step;
  list-style: none;
}
.neon-list li {
  position: relative;
  padding-left: 3rem;
  margin-bottom: 1rem;
  transition: text-shadow 0.3s ease;
}
.neon-list li::before {
  counter-increment: step;
  content: counter(step);
  position: absolute;
  left: 0;
  top: 0;
  width: 2.4rem;
  height: 2.4rem;
  background: var(--accent-color);
  color: var(--bg-gradient-end);
  font-weight: bold;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: 0 0 8px var(--accent-color), 0 0 16px var(--accent-color);
}

.checklist {
  max-width: 800px;
  margin: 2rem auto;
  background: var(--overlay-color);
  padding: 1.5rem;
  border-radius: 8px;
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.5);
  list-style: none;
  counter-reset: none;
}
.checklist li {
  position: relative;
  padding-left: 2.5rem;
  margin-bottom: 1rem;
  transition: text-shadow 0.3s ease;
}
.checklist li::before {
  content: '\2713';
  position: absolute;
  left: 0;
  top: 0;
  width: 2rem;
  height: 2rem;
  color: #FFF176;
  font-size: 1.5rem;
  font-weight: bold;
  display: flex;
  align-items: center;
  justify-content: center;
}

.planet-list {
  max-width: 800px;
  margin: 2rem auto;
  background: var(--overlay-color);
  padding: 1.5rem;
  border-radius: 8px;
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.5);
}
.planet-list > li {
  list-style: none;
  margin-bottom: 1.2rem;
  padding-left: 2.5rem;
  background: url('#') no-repeat left center;
  background-size: 1.8rem;
  transition: text-shadow 0.3s ease;
}
.planet-list ol li {
  list-style: decimal inside;
  background: none;
  padding-left: 0.5rem;
}

.card-list {
  max-width: 800px;
  margin: 2rem auto;
  background: none;
  padding: 0;
  border-radius: 0;
  box-shadow: none;
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  justify-content: center;
}
.card-list > li {
  background: var(--overlay-color);
  border-radius: 16px;
  box-shadow: 0 2px 8px rgba(0,0,0,0.3);
  padding: 1.2rem 2rem;
  margin: 0.5rem 0;
  min-width: 120px;
  max-width: 180px;
  list-style: none;
  font-weight: bold;
  font-size: 1.1rem;
  display: flex;
  flex-direction: column;
  align-items: center;
  transition: box-shadow 0.3s;
}
.card-list > li:hover {
  box-shadow: 0 0 16px var(--accent-color), 0 0 32px var(--accent-color);
}
.card-list ol {
  margin: 0.5rem 0 0 0;
  padding: 0 0 0 1.2rem;
  background: none;
  box-shadow: none;
}
.card-list ol li {
  font-weight: normal;
  font-size: 1rem;
  background: none;
  padding-left: 0.5rem;
  list-style: decimal inside;
}

.star-list {
  max-width: 800px;
  margin: 2rem auto;
  background: var(--overlay-color);
  padding: 1.5rem;
  border-radius: 8px;
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.5);
}
.star-list > li {
  list-style: none;
  margin-bottom: 1.2rem;
  padding-left: 2.5rem;
  background: url('#') no-repeat left center;
  background-size: 1.8rem;
  transition: text-shadow 0.3s ease;
}
.star-list ol li {
  list-style: decimal inside;
  background: none;
  padding-left: 0.5rem;
}

li:hover,
a:hover {
  text-shadow:
    0 0 8px var(--accent-color),
    0 0 16px var(--accent-color);
}


footer {
  display: block;
  text-align: center;
  margin: 0 auto;
  color: var(--accent-color);
  padding: 2rem 0 1rem 0;
}

footer a {
  color: #FFEB3B;
  text-decoration: none;
  position: relative;
  font-weight: 600;
  background: rgba(255, 235, 59, 0.1);
  padding: 0.3rem 0.6rem;
  border-radius: 4px;
  border: 1px solid rgba(255, 235, 59, 0.3);
  transition: all 0.3s ease;
}

footer a:hover {
  background: rgba(255, 235, 59, 0.2);
  border-color: #FFEB3B;
  text-shadow: 0 0 8px #FFEB3B;
  transform: translateY(-1px);
}

footer a::after {
  content: '';
  position: absolute;
  left: 0; right: 0; bottom: -2px;
  height: 2px;
  background: #FFEB3B;
  transform: scaleX(0);
  transition: transform 0.3s ease;
  transform-origin: left;
}

footer a:hover::after {
  transform: scaleX(1);
}

@keyframes drift {
  from { transform: translate(0, 0); }
  to   { transform: translate(-1000px, 1000px); }
}

@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(20px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

h2, h3, ol, ul, footer {
  opacity: 0;
  transform: translateY(20px);
  animation: fadeInUp 0.8s ease-out forwards;
}

h2:nth-of-type(1)     { animation-delay: 0.2s; }
ol:nth-of-type(1)     { animation-delay: 0.4s; }
h2:nth-of-type(2)     { animation-delay: 0.6s; }
ol:nth-of-type(2)     { animation-delay: 0.8s; }
h2:nth-of-type(3)     { animation-delay: 1.0s; }
ul:nth-of-type(1)     { animation-delay: 1.2s; }
h2:nth-of-type(4)     { animation-delay: 1.4s; }
ul:nth-of-type(2)     { animation-delay: 1.6s; }
h3                    { animation-delay: 1.8s; }
ul:nth-of-type(3)     { animation-delay: 2.0s; }
footer                { animation-delay: 2.2s; }


@media (max-width: 600px) {
  body {
    padding: 1rem;
  }
  h2 {
    font-size: clamp(1.4rem, 5vw, 2rem);
  }
}