/* Initially hide the side menu */
.side-menu {
  position: fixed;
  top: 0;
  right: -250px; /* hidden to the right */
  width: 250px;
  height: 100%;
  background-color: #fff;
  box-shadow: -2px 0 5px rgba(0,0,0,0.3);
  transition: right 0.3s ease;
  z-index: 1000;
}

.side-menu.open {
  right: 0;
}

.hamburger {
  position: fixed;
  top: 20px;
  right: 20px;
  font-size: 28px;
  cursor: pointer;
  z-index: 1100;
}

.close-btn {
  display: block;
  text-align: right;
  padding: 10px;
  font-size: 24px;
  cursor: pointer;
}


body {
  font-family: sans-serif;
  margin: 0;
  padding: 0;
}

.content {
  height: 2000px;
  padding: 0px;
}

#backToTop {
  position: fixed;
  bottom: 40px;
  right: 10px;
  width: 48px;
  height: 48px;
  display: none;
  cursor: pointer;
  opacity: 0.8;
  transition: opacity 0.3s ease;
  z-index: 888;
background-color: rgba(0, 0, 0, 0.3);
}

#backToTop:hover {
  opacity: 1;
}

body.small { font-size: 14px; }
body.medium { font-size: 16px; }
body.large { font-size: 20px; }

/* 所有文字都用 em 或 rem 单位，自动继承 body 的字体大小 */
p, h1, h2, h3, span, li {
  font-size: 1em;
  line-height: 1.6;
}


.font-size-selector {
  margin: 20px;
  text-align: center;
}

.font-size-selector span {
  font-family: Arial, sans-serif;
  font-weight: bold;
  margin: 0 10px;
  cursor: pointer;
  user-select: none;
  color: black;
  opacity: 0.6;
  font-size: 14px;
  transition: opacity 0.2s, transform 0.2s;
}

#mediumA {
  font-size: 18px;
}

#largeA {
  font-size: 24px;
}

.font-size-selector span:hover {
  opacity: 1;
  transform: scale(1.2);
}

.font-size-selector span.active {
  color: #007bff;
  opacity: 1;
  text-decoration: underline;
}

.font-size-selector span {
  font-size: 0.9em;
}

.main-shot {
	width: 100%;
	max-width: 1400px;
	margin: 0 auto;
	padding-left: 0px;
	text-align: center;
	}