/* 1 */
body {
  margin: 0;
  font-family: Arial, sans-serif;
}

/* 2 */
/* Header styling */
header {
  /* Arrangement */
  position: fixed;
  top: 0;
  left: 0;
  z-index: 1000;
  /* Property */
  height: 80px;
  width: 100%;
  /* Color */
  background-color: #333;
  color: #fff;
  /* Box */
  box-sizing: border-box;
  padding: 15px 20px;
  /* Control of children elements */
  display: flex;
  justify-content: space-between;
  align-items: center;
  /* Animation */
  transition: transform 0.3s ease-in-out;
}

header.hidden {
  transform: translateY(-100%);
}

header a {
  color: white;
  margin-left: 15px;
  text-decoration: none;
  display: inline-flex;
  align-items: center;
  gap: 5px;
}

header a img {
  width: 20px;
  height: 20px;
}

header a .link-text {
  display: inline;
}

@media (max-width: 768px) {
  header a .link-text {
    display: none;
  }

  header a img {
    width: 24px;
    height: 24px;
  }
}

/* Page content */
main {
  margin-top: 160px;
  margin-right: 15%;
  margin-left: 15%;
  margin-bottom: 100px;
  line-height: 1.6;
}

@media (max-width: 768px) {
  body {
    font-size: 18px;
  }

  main {
    margin-right: 0;
    margin-left: 0;
    padding: 0 15px;
  }

  h2 {
    font-size: 28px;
  }

  h3 {
    font-size: 24px;
  }

  h4 {
    font-size: 20px;
  }

  .after-buttons {
    padding: 0 15px;
    margin-bottom: 40px;
  }

  .after-button {
    padding: 15px 20px;
    font-size: 18px;
  }
}

/* After buttons */
.after-buttons {
  display: flex;
  flex-direction: column;
  gap: 20px;
  max-width: 600px;
  margin: 0 auto 60px;
}

.after-button {
  padding: 20px 40px;
  background-color: #333;
  color: white;
  border: none;
  border-radius: 10px;
  cursor: pointer;
  font-size: 20px;
  font-weight: bold;
  text-align: center;
  transition: background-color 0.3s;
}

.after-button:hover {
  background-color: #555;
}

.after-button.hidden {
  display: none;
}

/* Fotter */
footer {
  text-align: center;
  padding-right: 30%;
  padding-left: 30%;
  padding-top: 40px;
  padding-bottom: 40px;
  color: white;
  background-color: black;
}

@media (max-width: 768px) {
  footer {
    padding-right: 0;
    padding-left: 0;
  }
}


/* 3 */
.card {
  margin-bottom: 15px;
  padding: 20px;
  background-color: #eee;
  border-radius: 5mm;
}

/* Join steps with arrows */
.join-steps {
  position: relative;
}

.join-step {
  position: relative;
  margin-bottom: 40px;
  padding: 20px;
  background-color: #eee;
  border-radius: 5mm;
}

.join-step:last-child {
  margin-bottom: 15px;
}

.join-step::after {
  content: '↓';
  position: absolute;
  bottom: -55px;
  left: 50%;
  transform: translateX(-50%);
  font-size: 48px;
  font-weight: 900;
  color: #666;
  text-shadow: 1px 1px 0 #666, -1px -1px 0 #666, 1px -1px 0 #666, -1px 1px 0 #666;
}

.join-step:last-child::after {
  display: none;
}

.join-step .step-number {
  display: inline-block;
  width: 30px;
  height: 30px;
  line-height: 30px;
  text-align: center;
  background-color: #333;
  color: white;
  border-radius: 50%;
  font-weight: bold;
  margin-right: 10px;
}

.join-step p {
  margin: 0;
  display: inline;
}

.social-media {
  display: flex;
  justify-content: center;
  gap: 15px;
}

.social-media a {
  color: white;
  text-decoration: none;
  display: inline-flex;
  align-items: center;
  gap: 5px;
}

.social-media a img {
  width: 20px;
  height: 20px;
}

.social-media a .link-text {
  display: inline;
}

@media (max-width: 768px) {
  .social-media a .link-text {
    display: none;
  }

  .social-media a img {
    width: 24px;
    height: 24px;
  }
}

/* Tab buttons */
.tab-buttons {
  display: flex;
  gap: 10px;
  max-width: 800px;
  margin: 30px auto 20px;
}

.tab-button {
  padding: 10px 20px;
  background-color: #333;
  color: white;
  border: none;
  border-radius: 5px;
  cursor: pointer;
  font-size: 16px;
}

.tab-button:hover {
  background-color: #555;
}

.tab-button.inactive {
  background-color: #666;
  opacity: 0.7;
}

.tab-content {
  display: none;
}

.tab-content.active {
  display: block;
  animation: fadeIn 0.5s;
}

#activities,
#how-to-join {
  max-width: 800px;
  margin-left: auto;
  margin-right: auto;
}

/* Slideshow */
.slideshow-container {
  position: relative;
  width: 100%;
  max-width: 800px;
  margin: 0 auto;
  overflow: hidden;
  border-radius: 10px;
}

.slide {
  display: none;
  width: 100%;
}

.slide.active {
  display: block;
  animation: fadeIn 0.5s;
}

.slide img {
  width: 100%;
  height: 450px;
  object-fit: cover;
  display: block;
}

@media (max-width: 768px) {
  .slide img {
    height: 300px;
  }
}

@keyframes fadeIn {
  from { opacity: 0; }
  to { opacity: 1; }
}

/* Event items */
.event-item {
  margin-top: 20px;
  padding-top: 15px;
  border-top: 1px solid #ccc;
}

.event-item:first-child {
  margin-top: 10px;
  padding-top: 10px;
  border-top: none;
}

.event-item h4 {
  margin-top: 0;
  margin-bottom: 10px;
  font-weight: bold;
}

.event-images {
  display: flex;
  gap: 10px;
  margin-top: 10px;
}

.event-images img {
  width: calc(50% - 5px);
  height: 250px;
  object-fit: cover;
  border-radius: 5px;
  box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
}

@media (max-width: 768px) {
  .event-images {
    flex-direction: column;
  }

  .event-images img {
    width: 100%;
    height: 200px;
  }
}

/* Landing page introduction */
.landing-intro {
  max-width: 800px;
  margin: 30px auto 0;
  font-size: 18px;
  font-weight: bold;
  line-height: 1.8;
}

.landing-intro p {
  margin: 0.5em 0;
}