*{
    margin: 0;
    padding: 0;
    font-family: Tahoma, sans-serif;
    box-sizing: border-box;
    overflow: hidden;
    scroll-behavior: smooth;
}

header{
    background: linear-gradient(rgba(0, 0, 0, 0.317),rgba(0, 0, 0, 0.879)), url('../images/bg_fot_tlo.jpg') center;
    height: 100vh;
    width: 100vw;
    background-size: cover;
    display: flex;
    align-items: center;
    justify-content: center;
    flex-direction: column;
}

h1, h3{
    text-align: center;
    color: #ddd;
}

h1{
    position: relative;
    font-size: 60px;
    text-transform: uppercase;
}

h3{
    font-size: 24px;
    opacity: 0.9;
}

.tytul{
    position: relative;
    bottom: 0px;
    left: 0%;
    margin-left: 0px;
    margin-top: 18%;
    margin-bottom: 20px;
}

.btn1{
    position: absolute;
    bottom: 7%;
    left: 20%;
    width: 260px;
    height: 60px;
    background-color: transparent;
    border: 3px solid white;
    border-radius: 20px 0;
    color: white;
    font-size: 16px;
    }

.btn2{
    position: absolute;
    bottom: 7%;
    left: 80%;
    width: 260px;
    height: 60px;
    background-color: transparent;
    border: 3px solid white;
    border-radius: 0 20px;
    color: white;
    font-size: 16px;
}  

button:hover{
    background-color: rgba(255, 166, 0, 0.589);
    transition: all 0.5s ease-in;
    cursor: pointer;
}

section {
    background: linear-gradient(0.05turn, rgba(0, 0, 0, 0.317),rgba(255, 166, 0, 0.517),rgba(0, 0, 0, 0.589));
    width: 100vw;
    height: 100vh;
    margin: 0;
}

section h2 {
    font-size: 40px;
    text-align: center;
    color: #eee;
    margin-top: 30px;
}

section iframe{
    position: absolute;
    width: 80%;
    height: 80%;
    left: 10%
}

#arrow-up {
    width: 50px;
    height: 50px;
    border: 3px solid white;
    position: relative;
    top: -10%;
    left: 90%;
    border-radius: 50%;
    font-size: 35px;
    text-align: center;
    text-shadow: 0px -10px 0 white;
    color: white;
    overflow: hidden;
    padding-right: 0px;
}

#projekt-budowlany #arrow-up {
    position: relative;
    top: -16%;
    left: 90%;
} 

#arrow-down {
    width: 50px;
    height: 50px;
    border: 3px solid white;
    position: relative;
    top: 63%;
    left: 90%;
    border-radius: 50%;
    font-size: 35px;
    text-align: center;
    text-shadow: 0px -10px 0 white;
    color: white;
    overflow: hidden;
    padding-right: 0px;
    padding-top: 6px;
}

#projekt-budowlany #arrow-down {
    position: relative;
    top: 55%;
    left: 90%;
} 

#arrow-up:hover{
    background-color: rgba(255, 166, 0, 0.589);
    transition: all 0.5s ease-in;
    cursor: pointer;
}

#arrow-down:hover{
    background-color: rgba(255, 166, 0, 0.589);
    transition: all 0.5s ease-in;
    cursor: pointer;
}

img{
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.gallery{
    display: flex;
    flex-direction: row;
    justify-content: center;
    align-items: flex-start;
    margin-top: -70px;
}

.item{
    height: 70vh;
    width: 100%;
    flex: 1;
    cursor: pointer;
    transition: .3s ease flex;
    position: relative;
}

.item.show{
    flex: 8;
}

.caption{
    position: absolute;
    bottom: 0;
    left: 0;
    background-color: rgba(255, 255, 255, 0.534);
    padding: 20px;
    margin: 20px;
    border-radius: 8px;
    opacity: 0;
}

.item.show .caption{
    opacity: 1;
}

p{
    font-size: 22px;
}

#banner_allegro{
    height: 40px;
    width: 100%;
}