:root{
  --bg:#ffffff;
  --text:#1e293b;
  --green:#16a34a;
  --blue:#2563eb;
  --header1:#c7d2fe;
  --header2:#93c5fd;
  --sidebar:#e7f3e3;
}

*{
  margin:0;
  padding:0;
  box-sizing:border-box;
  font-family:Arial,sans-serif;
}

body{
  background:var(--bg);
  color:var(--text);
  line-height:1.6;
}

/* HEADER 1 */
.header-top{
  background:var(--header1);
  padding:25px 15px;
  text-align:center;
}

.logo-wrap{
  display:flex;
  justify-content:center;
  align-items:center;
  gap:12px;
}

.logo-wrap img{
  height:45px;
  max-width:100%;
}

/* HEADER 2 */
.header-nav{
  background:var(--header2);
  width:100%;
  transition:0.3s ease;
}

.header-nav.sticky{
  position:fixed;
  top:0;
  left:0;
  z-index:1000;
  box-shadow:0 4px 10px rgba(0,0,0,0.1);
}

.nav-inner{
  max-width:1200px;
  width:100%;
  margin:auto;
  display:flex;
  justify-content:center;
  align-items:center;
  padding:15px;
  position:relative;
}

nav{
  display:flex;
  gap:30px;
}

nav a{
  text-decoration:none;
  color:var(--text);
}

/* BURGER */
.burger{
  display:none;
  flex-direction:column;
  gap:6px;
  position:absolute;
  right:20px;
  cursor:pointer;
}

.burger span{
  width:28px;
  height:3px;
  background:var(--text);
  transition:0.3s;
}

.burger.active span:nth-child(1){
  transform:rotate(45deg) translate(5px,5px);
}
.burger.active span:nth-child(2){
  opacity:0;
}
.burger.active span:nth-child(3){
  transform:rotate(-45deg) translate(6px,-6px);
}

/* LAYOUT */
.container{
  max-width:1200px;
  width:100%;
  margin:auto;
  display:flex;
  gap:40px;
  padding:40px 20px;
}

main{
  flex:3;
  min-width:0;
}

.sidebar{
  flex:1;
  background:var(--sidebar);
  padding:20px;
  border-radius:8px;
}

/* HEADINGS */
h1{color:var(--green);margin-bottom:15px;}
h2{color:var(--blue);margin-bottom:15px;}
h3{color:var(--green);margin-bottom:15px;}

/* GALLERY */
.gallery{
  display:flex;
  flex-wrap:wrap;
  gap:20px;
  margin-top:20px;
}

.photo{
  flex:1 1 300px;
  overflow:hidden;
  border-radius:8px;
}

.photo img{
  width:80%;
  height:auto;
  transition:0.4s;
}

.photo:hover img{
  transform:scale(1.1);
}

/* FOOTER */
footer{
  background:var(--header1);
  padding:40px 20px;
}

.footer-grid{
  max-width:1200px;
  margin:auto;
  display:grid;
  grid-template-columns:1fr 1fr;
  gap:40px;
}

.copyright{
  text-align:center;
  margin-top:20px;
}

/* BUTTON UP */
#toTop{
  position:fixed;
  bottom:30px;
  right:30px;
  background:var(--blue);
  color:#fff;
  border:none;
  padding:12px 15px;
  border-radius:50%;
  cursor:pointer;
  display:none;
}

/* MOBILE */
@media(max-width:768px){

  .container{
    flex-direction:column;
  }

  .sidebar{
    order:2;
    margin-top:20px;
  }

  nav{
    position:absolute;
    top:100%;
    left:0;
    width:100%;
    flex-direction:column;
    background:var(--header2);
    display:none;
    padding:20px 0;
  }

  nav.active{
    display:flex;
  }

  .burger{
    display:flex;
  }

  .footer-grid{
    grid-template-columns:1fr;
  }
}