* {
  box-sizing: border-box;
}

body {
  padding: 20px;
  color: rgb(180, 27, 164);
  background-color: rgb(227, 74, 74);
  background-image: linear-gradient(to bottom, rgb(241, 223, 132), rgb(102, 233, 233));
  font-family: "Sekuya", system-ui;
}

.light-mode {
  background-color: rgb(78, 193, 225);
  color: rgb(210, 231, 232);
  box-shadow: 10px 5px5px 0 rgb(29, 26, 26);
  background-image: linear-gradient(to bottom, rgb(153, 252, 72), rgb(243, 127, 183));
}

main{
  min-height: 10px;
  background-color: rgd;
}

.center {
  margin-left: auto;
  margin-right: auto;
  width: 1200px;
  padding: 20px;

  /* TODO Add margins to center. */
}


footer {
  min-height: 50vh;
  padding: 200px;
  color: brown;
  background-color: blue;
  background-image: linear-gradient(to bottom, rgb(111, 212, 209), rgb(160, 200, 75));
  
  /* TODO Add footer light mode styles here. */
  background-color: rgb(93, 221, 84);
  color: blueviolet;
  box-shadow: 10px 5px 5px 0 rgba(77, 40, 40, 0.419);
  border: 15px solid grey;
  padding: 20px;
}

.light-mode footer {
    min-height: 50vh;

  /* TODO Add footer light mode styles here. */
  background-color: rgb(93, 221, 84);
  color: blueviolet;
  box-shadow: 10px 5px 5px 0 rgba(77, 40, 40, 0.419);
  border: 15px solid grey;
  padding: 20px;
}

button {
  /* 文字色：香檳金 */
  color: #f7e7ce;
  /* 邊框：古銅金 */
  border: 5px solid #d4af37;
  padding: 10px;
  width: 110px;
  /* 背景：深琥珀到焦糖色 */
  background-image: linear-gradient(to bottom, #8b4513, #b8860b);
  border-radius: 80px;

  position: relative;
  overflow: hidden;
  /* 增加一點深色陰影 */
  box-shadow: 0 4px 10px rgba(0, 0, 0, 0.3);
  font-weight: 600;
  cursor: pointer;
}

/* 這裡是流金特效 */
button::after {
  content: "";
  position: absolute;
  top: -50%;
  left: -150%;
  width: 80%;
  /* 寬度增加，讓光影感更飽滿 */
  height: 200%;
  /* 暖白到金色的漸層 */
  background: linear-gradient(to right,
      transparent,
      rgba(255, 250, 205, 0.1),
      rgba(255, 255, 255, 0.4),
      rgba(255, 250, 205, 0.1),
      transparent);
  transform: rotate(35deg);
  /* 動畫時間設為 2.5s，掃描感更優雅 */
  animation: liquid-gold 2.5s infinite ease-in-out;
}

@keyframes liquid-gold {
  0% {
    left: -150%;
  }

  45% {
    left: 150%;
  }

  /* 控制掃過速度 */
  100% {
    left: 150%;
  }
}



/* 定義特效：顏色變換 + 輕微縮放 */
@keyframes border-dance {

  0%,
  100% {
    transform: scale(1);
    /* 原始大小 */
    filter: hue-rotate(0deg);
    /* 原始顏色 */
    box-shadow: 0 0 10px rgba(0, 0, 0, 0.2);
  }

  50% {
    transform: scale(1.02);
    /* 變大 2% */
    box-shadow: 0 0 25px rgba(255, 255, 255, 0.4);
    /* 增加發光感 */
  }
}

.nana {
  font-size: 48px;
}

.line {
  display: flex;
  gap: 15px;
  justify-content:
    space-between;
  align-items: center;
}

.underline{
  display: flex;
  gap: 10px;
  justify-content: right;
  border-bottom: 1px solid rgb(255, 255, 255);
  margin-bottom: 0;
  padding: 0px;

}
.tab{
  display: inline-block;
  border: 1px solid white;
  border-bottom: none;
  padding: 10px;
  border-top-left-radius: 10px;
    border-top-right-radius: 10px;
}
.light-mode .tab {
  border-color: black;
}

.light-mode .underline{
  border-color: black;
}
a {
  color: rgb(228, 32, 231);
}
.light-mode a {
  color: rgb(0, 0, 0);
}
body {
    /* 讓所有顏色變化在 0.4 秒內平滑完成 */
    transition: background-color 1s ease, color 1s ease;
}

header, footer, .tab, button {
    transition: all 1s ease;
}


/* 設定背景裝飾 */
body::before,
body::after {
    content: "";
    position: fixed; /* 固定在螢幕兩側，滾動時也會留在原地 */
    top: 0;
    width: 150px; /* 圖片的寬度，你可以根據圖片大小調整 */
    height: 100%;
    background-image: url("./images/thumb-1920-551673.png");
    background-repeat: repeat-y; /* 垂直重複鋪滿 */
    background-size: contain; /* 確保圖片比例正確 */
    z-index: -1; /* 放在最底層，不會擋到文字 */
    pointer-events: none; /* 讓滑鼠可以穿透圖片，點擊後面的按鈕 */
}

/* 左側圖片 */
body::before {
    left: 0;
}

/* 右側圖片 */
body::after {
    right: 0;
}