* {
  box-sizing: border-box;
}

html,
body {
  margin: 0;
  padding: 0;
  min-height: 100%;
}

body {
  background: #121212;
  color: #fff;
  font-family: "Segoe UI", Tahoma, Geneva, Verdana, sans-serif;
  font-size: 16px;
}

a {
  color: inherit;
  text-decoration: none;
}

img {
  max-width: 100%;
  height: auto;
}

.page-wrapper {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

.main-content {
  flex: 1;
}

header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 16px;
  padding: 16px 30px;
  background: #1e1e1e;
  border-bottom: 1px solid #333;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.45);
}

.a1 {
  font-size: 1.5rem;
  font-weight: 700;
  transition: 0.25s ease;
}

.a1:hover {
  color: #0af;
}

.hero {
  text-align: center;
  padding: 45px 20px 15px;
}

.hero h1 {
  margin: 0 0 12px;
  font-size: clamp(2rem, 5vw, 3.5rem);
}

.hero p {
  margin: 8px 0;
  color: #cfcfcf;
}

.rp-grid {
  width: min(1000px, 100%);
  margin: 0 auto;
  padding: 35px 20px 60px;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 22px;
}

.rp-card {
  background: #1e1e1e;
  border: 1px solid #333;
  border-radius: 16px;
  overflow: hidden;
  box-shadow: 0 0 12px rgba(0, 0, 0, 0.55);
  transition: 0.25s ease;
}

.rp-card:hover {
  transform: translateY(-6px) scale(1.02);
  border-color: #0af;
  box-shadow: 0 0 24px rgba(0, 170, 255, 0.4);
}

.rp-card img {
  width: 100%;
  height: 170px;
  object-fit: cover;
  transition: 0.25s ease;
}

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

.rp-info {
  padding: 16px;
  text-align: center;
}

.rp-info h2 {
  margin: 0 0 10px;
  font-size: 1.35rem;
}

.rp-info p {
  margin: 0 0 14px;
  color: #cfcfcf;
}

.download-btn {
  display: inline-block;
  padding: 10px 16px;
  background: #0af;
  color: #121212;
  border-radius: 10px;
  font-weight: 700;
  transition: 0.25s ease;
}

.download-btn:hover {
  background: #0077cc;
  color: #fff;
}

.open-btn {
  position: fixed;
  top: 20px;
  right: 15px;
  z-index: 1000;
  padding: 10px 18px;
  background: #0af;
  color: #121212;
  border: none;
  border-radius: 10px;
  cursor: pointer;
  font-size: 1rem;
  font-weight: 700;
  transition: 0.25s ease;
}

.open-btn:hover {
  background: #0077cc;
  color: #fff;
}

dialog.dialog-style {
  border: none;
  border-radius: 14px;
  background: #1e1e1e;
  color: #fff;
  padding: 22px;
  width: 90%;
  max-width: 420px;
  box-shadow: 0 0 24px rgba(0, 170, 255, 0.75);
  animation: dialogFadeIn 0.25s ease;
}

dialog::backdrop {
  background: rgba(0, 0, 0, 0.65);
  backdrop-filter: blur(4px);
}

.dialog-content h2,
.dialog-content h3 {
  margin: 0 0 16px;
  font-size: 1.35rem;
}

.dialog-content a {
  display: block;
  margin: 10px 0;
  color: #0af;
  font-size: 1rem;
}

.dialog-content a:hover {
  text-decoration: underline;
}

.close-btn {
  margin-top: 16px;
  padding: 9px 18px;
  background: crimson;
  color: #fff;
  border: none;
  border-radius: 10px;
  cursor: pointer;
  font-size: 1rem;
}

.close-btn:hover {
  background: darkred;
}

#scrollToTopBtn {
  position: fixed;
  bottom: 22px;
  right: 15px;
  z-index: 1000;
  background: #3f3f3f;
  color: #fff;
  border: none;
  border-radius: 10px;
  padding: 12px 16px;
  font-size: 18px;
  cursor: pointer;
  display: none;
  box-shadow: 0 4px 10px rgba(0, 0, 0, 0.35);
  transition: 0.25s ease;
}

#scrollToTopBtn:hover {
  background: #646464;
}

#scrollToTopBtn:active {
  transform: scale(0.92);
}

footer {
  margin-top: auto;
  background: #1e1e1e;
  text-align: center;
  padding: 16px 12px;
  border-top: 1px solid #333;
  box-shadow: 0 -2px 8px rgba(0, 0, 0, 0.45);
}

footer h1,
footer h2 {
  margin: 0;
  font-size: 1rem;
}

footer p {
  margin: 8px 0 0;
  color: #cfcfcf;
}

@keyframes dialogFadeIn {
  from {
    opacity: 0;
    transform: scale(0.9);
  }

  to {
    opacity: 1;
    transform: scale(1);
  }
}

@media (max-width: 768px) {
  header {
    flex-direction: column;
    align-items: center;
    text-align: center;
  }

  .rp-grid {
    padding: 25px 14px 50px;
  }
}

@media (max-width: 480px) {
  body {
    font-size: 14px;
  }

  header {
    padding: 14px;
  }

  .open-btn {
    top: 12px;
    right: 10px;
    padding: 8px 14px;
  }

  dialog.dialog-style {
    width: 95%;
    padding: 18px;
  }

  .close-btn {
    width: 100%;
  }
}