/* Common header styles */
header {
    background-color: #1d3557;
    color: #fff;
    padding: 10px 20px;
}

header .brand {
    display: flex;
    align-items: center;
    justify-content: space-between;
}

header .brand a {
    color: #fff;
    font-size: 1.2rem;
    font-weight: bold;
}

#menu-btn {
    display: none;
    background: none;
    border: none;
    color: #fff;
    font-size: 1.5rem;
    cursor: pointer;
}

#main-nav {
    display: flex;
    gap: 1rem;
}

#main-nav a {
    color: #fff;
    text-decoration: none;
}


/* === 現在の活動（タイムライン） === */
#current-activities.card{
  margin-top:2rem; padding:1.25rem; background:#fff; border:1px solid #e6e6e6; border-radius:10px;
  box-shadow:0 2px 10px rgba(0,0,0,.04);
}
#current-activities h2{ margin-top:0; color:#1d3557; }
#current-activities .timeline{ list-style:none; margin:0; padding:0 0 0 1.25rem; position:relative; }
#current-activities .timeline::before{
  content:""; position:absolute; left:.4rem; top:.2rem; bottom:.2rem; width:2px; background:#e0e0e0;
}
#current-activities .timeline li{ position:relative; margin:0 0 1rem 0; padding-left:.5rem; }
#current-activities .timeline li::marker{ content:""; }
#current-activities .timeline li::before{
  content:""; position:absolute; left:-.05rem; top:.25rem; width:.6rem; height:.6rem; border-radius:50%;
  background:#457b9d; box-shadow:0 0 0 3px #eef4fb;
}
#current-activities time{ display:inline-block; font-weight:700; color:#457b9d; margin-right:.5rem; }
#current-activities p{ margin:.25rem 0 0; color:#444; }
#current-activities a{ color:#e63946; text-decoration:none; }
#current-activities a:hover{ text-decoration:underline; }

@media (max-width: 600px) {
    #menu-btn {
        display: block;
    }

    #main-nav {
        display: none;
        flex-direction: column;
        position: absolute;
        top: 100%;
        left: 0;
        width: 100%;
        background-color: #1d3557;
    }

    #main-nav.show {
        display: flex;
    }
}