* {
    box-sizing: border-box;
}
body {
    margin: 0;
    background-color: white;
    color: #333333;
    font-family: Poppins, sans-serif;
    line-height: 1.5;
}
.header {
    background-color: #246b40;
}
.header-content {
    position: relative;
    width: 90%;
    max-width: 1100px;
    margin: 0 auto;
    padding: 20px 0;
    display: grid;
    grid-template-columns: 1fr auto;
    align-items: center;
}
.site-name{
    color: white;
    font-size: 20px;
    font-weight: bold;
    text-decoration: none;
}
.menu-button {
    display: none;
    background-color: transparent;
    color: white;
    border: 1px solid white;
    border-radius: 4px;
    padding: 4px 10px;
    font-size: 24px;
    cursor: pointer;
}
nav a {
    color: white;
    margin-left: 25px;
    text-decoration: none;
}
nav a:hover {
    text-decoration: underline;
}
main {
    background-color: #eff8f0;
}
.intro {
    width: 90%;
    max-width: 1100px;
    margin: 0 auto;
    padding: 65px 0;
    display: grid;
    grid-template-columns: 1fr 1fr;
    align-items: center;
    gap: 30px;
}
.intro-image {
  text-align: center;
}
.intro-image img {
    width: 270px;
    max-width: 100%;
    border: 4px solid #e4eee7;
    border-radius: 50%;
}
.intro-text p {
    margin: 10px 0;
}
h1 {
    color: #246b40;
    font-size: 38px;
    margin: 5px 0;
}
.button {
    display: inline-block;
    margin-top: 15px;
    padding: 10px 20px;
    border-radius: 4px;
    background-color: #2e7d4f;
    color: white;
    text-decoration: none;
}
.button:hover {
    background-color: #246b40;
}
.publications {
    background-color: #eef6fc;
    border-top: 1px solid #dddddd;
    padding: 50px 5% 65px;
}
.publications h2 {
    margin: 0;
    color: #246b40;
    font-size: 28px;
    text-align: center;
}
.heading-line {
    width: 50px;
    height: 3px;
    margin: 10px auto 20px;
    background-color: #3475a6;
}
.section-description, #message {
    text-align: center;
}
.publication-grid {
    max-width: 1100px;
    margin: 30px auto 0;
    display: grid;
    grid-template-columns: 1fr 1fr 1fr;
    gap: 20px;
}
.publication-card {
    padding: 25px 20px;
    border-radius: 5px;
    background-color: #246b40;
    color: white;
    text-align: center;
}
.blue-card {
    background-color:#205b86;
}
.paper-icon {
    width: 48px;
    height: 48px;
}
.publication-card h3 {
    font-size: 19px;
}
.publication-card p {
    margin: 8px 0;
}
footer {
    padding: 25px;
    background-color: #205b86;
    color: white;
    text-align: center;
}
footer p {
    font-weight: bold;
    margin: 0 0 8px;
}
footer a {
  color:white;
}
@media only screen and (max-width: 800px) {
    .menu-button {
        display: block;
    }
    #menu {
        display: none;
        position: absolute;
        top: 100%;
        right: 0;
        width: 190px;
        background-color: #246b40;
        border: 1px solid white;
        z-index: 1;
    }
    #menu.active {
        display: block;
    }
    #menu a {
        display: block;
        margin: 0;
        padding: 12px 18px;
        text-align: left;
    }
    .intro {
        grid-template-columns: 1fr;
        text-align: center;
    }
    .publication-grid {
        grid-template-columns: 1fr;
    }
}
@media only screen and (max-width: 480px) {
    .intro {
        padding: 40px 0;
    }
    .intro-image img {
        width: 220px;
    }
    h1 {
        font-size: 32px;
    }
}
@font-face {
    font-family: Poppins;
    src: url('Poppins-Regular.ttf');
}