html,
body {
    /*visibility: hidden;*/
    background-color: #010101;
    /* font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif; */
    color: white;
    font-size: 18px;
    scroll-behavior: smooth;

    font-family: "Montserrat", sans-serif;
    font-optical-sizing: auto;
    font-weight: 400;
    /* font-style: normal; */
}


h1 {
    text-align: center;
    font-size: 1.8em;
    font-weight: 400;
    margin: auto;
    padding: 1em
}

h2 {
    font-size: 1em;
    text-align: center;
    font-weight: 400;
    font-size: 1em;
    margin: auto;
}

h3 {
    font-size: 1.2em;
    font-weight: 400;
}


* {
    box-sizing: border-box;
}

a {
    text-decoration: none;
    color: white;
}

.navbar {
    /* top: -2em; */
    position: relative;
    /* margin-bottom: 0.5em; */
    margin-left: 0.5em;
    display: flex;
    z-index: 4;
}

.navbar a {
    text-decoration: none;
    color: white;
    font-size: 1em;
    padding: .5em;
}

#backtotop {
    position: fixed;
    bottom: 50px;
    right: 10px;
    z-index: 5;
    font-size: xx-large;
}

.logo {
    width: 180px;
    height: auto;
    position: static;
    display: flex;
    text-align: center;
    z-index: 3;
    justify-content: center;
    margin: 10px auto;
}

.logo img {
    width: 100%;
    /* display: flex; */
    top: 0;
    /* z-index: 5; */
    /* height: 160px; */
}

.main_logo {
    display: flex;
    position: relative;
    justify-content: center;
    vertical-align: center;
    width: 90%;
    flex-direction: column;

    margin: auto;
    padding-bottom: .3rem;
}

.main_logo img {
    padding-bottom: .6rem;
    object-fit: cover;

}

.form {
    display: flex;
    justify-content: center;
    align-items: center;
    margin: auto;
    padding: 1rem;
}

.form .etiket {
    margin-right: 1rem;

}

.alan {
    display: grid;
    grid-template-columns: 1fr 2fr;
    grid: 1rem;
    justify-content: start;
    align-items: start;
    margin: auto;
    padding: .5rem;
    min-width: 300px;
}

.form .buton-grup {
    display: flex;
    justify-content: end;
    margin-top: 1rem;
    gap: 1rem;
}

button {
    padding: 0.5rem 1rem;
    font-weight: 700;
    cursor: pointer;
}

#myVideo {
    position: relative;
    justify-content: center;
    vertical-align: center;
    width: 90%;
    margin: auto;
}

.container {
    display: flex;
    position: relative;

    justify-content: center;
    vertical-align: center;
    padding: auto;

}

#container_top {
    display: flex;
    flex-direction: column;
    justify-content: center;
    text-align: center;
}

.tanitim {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    /* align-items: center;*/
}

.panel {
    position: relative;
    /* overlay için gerekli */
    overflow: hidden;
    justify-items: center;
    align-items: center;
    text-align: center;
    z-index: 1;
    margin: 0 auto;
    aspect-ratio: 16/9;
}

.panel img {
    width: 100%;
    height: 100%;
    padding: 0.3rem;
    object-fit: cover;
    /* görüntünün oranını koruyarak kaplamak için */
    padding: 0.3rem;
    justify-content: center;
}

.panel-tanitim {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.7);
    color: white;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    opacity: 0;
    transition: opacity 0.3s ease, visibility 0.3s ease;
}

.panel:hover .panel-tanitim {
    opacity: 1;
    transition: opacity 0.3s ease, visibility 0.3s ease;

    visibility: visible;
}

.panel-tanitim h3 {
    margin: 0;
    padding: 10px;
    color: white;
}

.panel-tanitim p {
    margin: 5px 0;
    color: white;
}


/* opsiyonel: büyük ekranlarda genişliği sınırlamak için */
@media (min-width: 768px) {
    .container {
        max-width: 1600px;
        margin: 0 auto;
    }
}

@media (max-width:768px) {

    html,
    body {
        font-size: .9em;
    }

    .logo {
        width: 110px;
        /* height: 90px; */
    }

    h1 {
        font-size: 1.4em;
        padding: 0.5em
    }

    h2 {
        font-size: 1.2em;
    }

    h3 {
        font-size: 1em;
    }

    .navbar a {
        font-size: 0.9em;
        padding: .3rem .3rem;
    }


}