/* 見出し装飾: 左ボーダー + 背景色 */
.content main h2 {
    border-left: 4px solid #4a90d9;
    background: rgba(74, 144, 217, 0.08);
    padding: 0.5em 0.8em;
    margin-top: 1.8em;
    margin-bottom: 0.6em;
    border-radius: 0 4px 4px 0;
}

.content main h3 {
    border-left: 3px solid #6ab04c;
    background: rgba(106, 176, 76, 0.06);
    padding: 0.4em 0.7em;
    margin-top: 1.4em;
    margin-bottom: 0.5em;
    border-radius: 0 3px 3px 0;
}

.content main h4 {
    border-left: 2px solid #f0932b;
    padding: 0.3em 0.6em;
    margin-top: 1.2em;
    margin-bottom: 0.4em;
}

/* Ko-fi サイドバーリンク */
#kofi-sidebar {
    padding: 1em 1.2em;
    margin-top: 1em;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    text-align: center;
}
#kofi-sidebar a {
    color: #ff5e5b;
    text-decoration: none;
    font-size: 0.85em;
    opacity: 0.8;
    transition: opacity 0.2s;
}
#kofi-sidebar a:hover {
    opacity: 1;
    text-decoration: underline;
}