:root {
    --color-background: #ffffff;
    --color-therme: rgb(134, 186, 226);
    --color-text: rgb(0, 0, 0);
    --color-text-h: rgb(0, 129, 142);
    --color-box: rgb(255, 255, 255);
}

body {
    margin: 0;
    padding: 0;
    height: 100%;
    background-color: var(--color-background);
    color: var(--color-text);
    font-family:'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
}

h1 {
    font-size: 2em;
    color: var(--color-text-h);
}

h2 {
    font-size: 1.7em;
}

h3 {
    font-size: 1.5em;
}

h1, h2, h3 {
    font-weight: normal;
    margin: 0;
    padding: 0;
    text-align: center;
}


nav {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0 20px;
    margin-bottom: 20px;
    background-color: var(--color-box);
    border-bottom: 1px solid var(--color-therme);
}

nav a {
    color: var(--color-text-h);
    text-decoration: none;
    font-size: 1.2em;
}
nav a:hover {
    opacity: 0.7;
    text-decoration: underline;
}

nav div a {
    margin-left: 20px;
}

.logo {
    display: table;
    float: left;
}
.logo img, .logo h1 {
    display: table-cell; 
    vertical-align: middle; 
    text-align: center;
}
.logo img {
    width: 80px;
    height: 80px;
}

@media (max-width: 500px) {
    nav {
        flex-direction: column;
        align-items: center;
        height: auto;
        padding-bottom: 10px;
    }
    nav h1 {
        margin-bottom: 10px;
    }
    nav a {
        margin: 10px;
    }
}

button {
    border: none;
    background-color: var(--color-box);
    color: var(--color-text);
    padding: 10px 20px;
    font-size: 1.2em;
    cursor: pointer;
    transition: all 0.2s;
    margin: auto;
}

button:hover {
    opacity: 0.8;
}


.box {
    max-width: 800px;
    padding: 20px;
    margin: 0 auto;
}

.box p {
    font-size: 1.1em;
}

footer {
    position: absolute;
    bottom: 0;
    width: 100%;
    text-align: center;
    font-size: 0.8em;
    height: 30px;
}
footer p {
    margin: 0;
    margin-bottom: 5px;
}
footer a {
    color: #000;
    text-decoration: none;
}
footer a:hover {
    text-decoration: underline;
}