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

body > header {
    background-color: #ff9999;
    display: flex;
    align-items: center;
    height: 130px;
    padding: 0 30px;
    padding-left: calc((100% - 1200px) / 2);
}

body > header nav {
    margin-left: auto;
}

body > header ul {
    display: flex;
    align-items: center;
    height: 60px;
    justify-content: flex-end;
    gap: 50px;
}

body > header ul li {
    list-style: none;
    font-weight: bold;
}

body > header li a {
    text-decoration: none;
    color: white;
}

main {
    background-color: #e0e0e0;
    padding: 20px 0;
}

.content_all {
    display: flex;
    gap: 15px;
    max-width: 1200px;
    margin: 0 auto;
}

.main_left {
    background: white;
    padding: 15px;
    display: flex;
    flex-direction: column;
    gap: 20px;
    flex: 1;
}

.main_right {
    background: white;
    padding: 15px;
    display: flex;
    flex-direction: column;
    gap: 20px;
    width: 300px;
    flex-shrink: 0;
}

.main_content_area {
    background: transparent;
    padding: 10px;
    min-height: 400px;
}

.main_content_left {
    background: transparent;
    padding: 10px;
    min-height: 100px;
}

.main_content_right {
    background: transparent;
    padding: 10px;
    min-height: 100px;
}

.main_supplementary {
    background: transparent;
    padding: 10px;
    min-height: 400px;
}

.article_tile {
    border: 3px solid #4a4a4a;
    border-radius: 10px;
    min-height: 200px;
    display: flex;
    gap: 15px;
    padding: 15px;
}

.dtg {
    background: #4a4a4a;
    color: white;
    padding: 10px;
    text-align: center;
    min-width: 50px;
    display: flex;
    flex-direction: column;
    justify-content: center;
    flex-shrink: 0;
}

.article_content h3 {
    margin-bottom: 5px;
}

.article_content p {
    margin-bottom: 10px;
}

footer{
    background-color: #4a4a4a;
    color: #ffffff;
    bottom: 0;
    left: 0;
    right: 0;
    height: 300px;
    width: 100%;
    padding: 10px;
    text-align: left;
    }

@media (max-width: 770px) {
    body > header {
        flex-direction: column;
        align-items: flex-start;
        height: auto;
        padding: 10px;
        gap: 10px;
    }

    body > header nav {
        width: 100%;
        margin-left: 0;
    }

    body > header ul {
        display: flex;
        flex-direction: column;
        align-items: flex-start;
        gap: 10px;
        margin: 0;
        padding: 0;
        height: auto;
    }
}

@media (max-width: 770px) {
    .content_all {
        flex-direction: column;
    }

    .main_right {
        width: 100%;
        margin: 10px 0;
        gap: 10px;
        box-sizing: border-box;
    }

    .main_content_right,
    .main_supplementary {
        box-sizing: border-box;
    }
}

@media (max-width: 770px) {
    .main_content_left,
    .main_content_right,
    .main_content_area,
    .main_supplementary {
        min-height: auto;
        padding: 10px;
    }
}