@charset "UTF-8";
@import url(common.css);

:root{
  --introBtn_Defalt:#0059ff;
  --introBtn_Hover:#004edf;
}

/* ------------------------------------------------------------------------- */
/* INTRO
/* ------------------------------------------------------------------------- */
.col { display: flex; flex-direction: column;}

#intro_wrap {
  width: 100%; 
  position: relative;
  overflow: hidden;
}
#intro_wrap .inner {
  display: flex; align-items: center; justify-content: center;
  max-width: 100%; min-height: 100dvh;
  background: url(../img/common/intro/intro_bg_HG.jpg) no-repeat center / cover;
  transition: background-image 0.5s linear;
}
#intro_wrap .inner.hg {background-image: url(../img/common/intro/intro_bg_HG.jpg);}
#intro_wrap .inner.ndg {background-image: url(../img/common/intro/intro_bg_NDG.jpg);}
#intro_wrap .inner.gg {background-image: url(../img/common/intro/intro_bg_GG.jpg);}
#intro_wrap .inner.ysg {background-image: url(../img/common/intro/intro_bg_YSG.jpg);}
#intro_wrap .container {
  display: flex; align-items: flex-start; justify-content: space-between; gap: 5rem;
  width: 100%; max-width: 174rem; 
  position: relative;
  transition: padding 0.3s ease, flex 0.3s ease;
}


/* header */
#intro_wrap .header { 
  flex-shrink: 0;
  width: 40rem; 
  display: flex; flex-direction: column; gap: 6rem;
  position: relative; z-index: 10;
  transition: width 0.3s ease , gap 0.3s linear;
}
#intro_wrap .header .h_logo {height: 5.6rem; transition: height 0.2s ease;}
  #intro_wrap .header .h_logo a {height: 100%;}
  #intro_wrap .header .h_logo img {height: 100%;}
#intro_wrap .header .h_title {
  font-size: 4.4rem; line-height: 1.4; letter-spacing: -0.044rem; color: var(--white);
  transition: font-size 0.3s ease;
}
#intro_wrap .header .h_title span {font-weight: 700;}


/* main - 4대강 소개 */
#intro_wrap .visual {
  display: flex; gap: 1.6rem;
  width: 100%;
  position: relative;
  transition: flex 0.4s ease-in-out; 
}
#intro_wrap .visual .con {
  flex: 1 1 0%;
  display: flex; align-items: flex-end;
  width: calc((100% - 4.8rem)/4); min-height: 66dvh; max-height: 72rem;
  border-radius: 1.8rem;
  background: url(../img/common/intro/intro_HG.png) no-repeat center / cover;
  position: relative;
  box-shadow: 0 0.7rem 1.4rem rgba(0, 0, 0, 0.12);
  transition: flex 0.5s ease-in-out, height 0.5s ease, min-height 0.5s ease;
  overflow: hidden;
}
#intro_wrap .visual .con:focus {outline: 2px dashed var(--primary-30);}

#intro_wrap .visual .con.ndg {background-image: url(../img/common/intro/intro_NDG.png);}
#intro_wrap .visual .con.gg {background-image: url(../img/common/intro/intro_GG.png);}
#intro_wrap .visual .con.ysg {background-image: url(../img/common/intro/intro_YSG.png);}

#intro_wrap .visual .con_txt{ 
  gap: 2.8rem; 
  width: 100%;
  padding: 4rem;
  color: var(--white);
  position: absolute; left: 0; bottom: 0; 
  transition: padding 0.2s ease;
}
#intro_wrap .visual .con_txt .tit{ 
  display: inline-flex; align-items: center; gap: 0.4rem;
  font-weight: 700; font-size: 4rem; line-height: 4.4rem;
  position: relative; 
  transition: font 0.2s ease;
}
#intro_wrap .visual .con_txt .tit::after{content: '';
  flex-shrink: 0;
  width: 4.4rem; height: 4.4rem;
  background: url(../img/common/intro/ico_intro_arrow.svg) no-repeat center / contain;
}
#intro_wrap .visual .con.on .con_txt .tit::after{ display: none; }

#intro_wrap .visual .con_txt .effect { 
  display: none;
  width: 100%;
  position: relative; bottom: -100px;
  opacity: 0;
  transition: width 0.5s linear;
}
#intro_wrap .visual .con_txt .river_info {
  margin-bottom: 2.8rem;
  font-size: 1.8rem; line-height: 1.7; 
}

/* 4대강 소개 on/off */
#intro_wrap .visual .con.on {flex: 3 1 0%;}
#intro_wrap .visual .con.on .con_txt {width: 62rem;}
#intro_wrap .visual .con.on .effect {
  display: block;
  animation: txtUp 0.5s ease 0.1s forwards;
}
@keyframes txtUp {
  to {bottom: 0; opacity: 1;}
}

/* 바로가기 버튼 */
#intro_wrap .visual .con_txt .effect .riverBtn {
  display: block;
  width: 20rem; padding: 2rem 6.5rem; 
  border-radius: 1.2rem;
  font-weight: 600; font-size: 1.8rem; text-align: center; letter-spacing: -0.02rem;
  background-color: var(--introBtn_Defalt); color: var(--white);
  transition: background-color 0.3s ease, width 0.3s ease;
}
#intro_wrap .visual .con_txt .effect .riverBtn:hover{background-color: var(--introBtn_Hover);}

/* copyright */
#intro_wrap .copyright{
  font-weight: 300; font-size: 1.3rem; line-height: 1.5; color: var(--white);
  position: absolute; 
  left: 0; bottom: .5rem;
  transition: bottom 0.2s ease;
}





/* ------------------------------------------------------------------------- */
/* MediaQuery
/* ------------------------------------------------------------------------- */
/* ===== 1788px ===== */
@media (max-width: 1788px) {
  #intro_wrap .header {width: auto;}
  #intro_wrap .header .h_title {font-size: 4rem;}
  #intro_wrap .visual .con_txt {padding: 4rem 2vw;}
  #intro_wrap .visual .con.on .con_txt {width: calc((100vw - 450px)*0.475);}
  #intro_wrap .visual .con.off .con_txt {padding: 4rem 1.5vw;}
}


/* ===== 1600px ===== */
@media (max-width: 1600px) {
  #intro_wrap .header {gap: 3rem;}
  #intro_wrap .header .h_logo {height: 5.2rem;}
  #intro_wrap .header .h_title {font-size: 3.4rem;}

  #intro_wrap .visual .con.on .con_txt {width: calc((100vw - 400px)*0.475);}
  #intro_wrap .visual .con_txt .tit {font-size: 3.6rem;}
  #intro_wrap .visual .con.off .con_txt .tit {font-size: 3.4rem;}
  #intro_wrap .visual .con.off .con_txt .tit::after {width: 3.4rem; height: 3.4rem;}
  #intro_wrap .visual .con_txt .river_info {font-size: 1.7rem;}
  #intro_wrap .visual .con_txt .effect .riverBtn {
    width: fit-content;
    padding: 2rem 6rem;
    font-size: 1.7rem;
  }
}


/* ===== 1440px ===== */
@media (max-width: 1440px) {
  #intro_wrap .visual .con_txt {padding: 3rem 2vw;}
  #intro_wrap .visual .con.off .con_txt {padding: 3rem 1.2vw;}
  #intro_wrap .visual .con.off .con_txt .tit {font-size: 3rem; line-height: 3.6rem;}
  #intro_wrap .visual .con.off .con_txt .tit::after {width: 3.4rem; height: 3.4rem;}

  #intro_wrap .copyright {bottom: 2rem;}
}


/* ===== 1280px ===== */
@media (max-width: 1280px) {
  #intro_wrap .container {
    flex-direction: column;
    min-height: 100dvh;
    padding: 2.4rem 0 10rem 0;
  }
  #intro_wrap .header {width: 100%;}
  #intro_wrap .header .h_logo {height: 4.2rem;}
  #intro_wrap .header .h_title {line-height: 4.5rem;}

  #intro_wrap .visual {flex: 1; align-items: center;}
  #intro_wrap .visual .con {min-height: 42.5rem; height: calc(100dvh - 340px);}
  #intro_wrap .visual .con.on .con_txt {width: calc((100vw - 48px)*0.475);}
  #intro_wrap .visual .con.off .con_txt {padding: 3rem 2rem;}
}


/* ===== 1024px ===== */
@media (max-width: 1024px) {
  #intro_wrap .visual .con_txt .tit {font-size: 3rem;}
  #intro_wrap .visual .con_txt .tit::after {width: 3.6rem; height: 3.6rem;}

  #intro_wrap .visual .con.off .con_txt {padding: 3rem 1.5rem;}
  #intro_wrap .visual .con.off .con_txt .tit {font-size: 2.4rem; line-height: 3rem;}
  #intro_wrap .visual .con.off .con_txt .tit::after {width: 3rem; height: 3rem;}

  #intro_wrap .visual .con_txt .effect .riverBtn {
    padding: 0.9rem 5rem 1.1rem 5rem;
    line-height: 3rem;
  }
}


/* ===== 768px ===== */
@media (max-width: 768px) {
  #intro_wrap .container {
    gap: 3.2rem;
    padding: 2rem 0 9rem 0;
  }
  #intro_wrap .header {gap: 3.2rem;}
  #intro_wrap .header .h_logo {height: 3.2rem;}
  #intro_wrap .header .h_title {font-size: 3rem; line-height: 4rem;}

  #intro_wrap .visual {flex-direction: column; justify-content: center; gap: 1.2rem;}
  #intro_wrap .visual .con {
    width: 100%; min-height: 13.6rem; height: 100%; max-height: 16rem;
    border-radius: 2rem;
  }
  #intro_wrap .visual .con_txt {padding: 2rem;}
  #intro_wrap .visual .con_txt .tit {font-size: 2.8rem; line-height: 3.4rem;}
  #intro_wrap .visual .con_txt .tit::after {width: 3.4rem; height: 3.4rem;}
  #intro_wrap .visual .con_txt .river_info {
    margin-bottom: 3.6rem;
    font-size: 1.6rem; line-height: 1.6;
  }
  #intro_wrap .visual .con_txt .effect .riverBtn {
    width: 100%;
    font-size: 1.6rem;
  }

  #intro_wrap .visual .con.on {min-height: 30rem;}
  #intro_wrap .visual .con.on .con_txt {gap: 1.2rem; width: 100%;}
  #intro_wrap .visual .con.on .effect {animation-delay: 0s;}

  #intro_wrap .visual .con.off .con_txt {padding: 2rem;}
  #intro_wrap .visual .con.off .con_txt .tit {font-size: 2.8rem; line-height: 3.4rem;}
  #intro_wrap .visual .con.off .con_txt .tit::after {width: 3.4rem; height: 3.4rem;}

  #intro_wrap .copyright {width: 100%; font-size: 1.2rem; line-height: 1.8rem; text-align: center;}
}


/* ===== 480px ===== */
@media screen and (max-width:480px){
  #intro_wrap .visual .con.on {min-height: 34.2rem;}
  #intro_wrap .visual .con_txt .effect .riverBtn { width: 100%; }
}