/* about.css */

/* コンテナ設定（calc-div.htmlと共通の質感に） */
.about-wrapper {
    padding: 40px 10px;
    background-color: #f8f9fa;
    display: flex;
    flex-direction: column;
    align-items: center;
}

.container {
    background: white;
    padding: 40px;
    border-radius: 15px;
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.05);
    width: 95%;
    max-width: 900px;
}

/* イントロ・テキスト */
.about-intro {
    text-align: center;
    margin-bottom: 50px;
}

.about-intro h1 {
    color: #1a365d;
    margin-bottom: 20px;
}

.bio-text {
    line-height: 1.8;
    color: #4a5568;
    text-align: left;
    max-width: 800px;
    margin: 0 auto;
}

/* タイムライン */
.career-timeline {
    margin-bottom: 60px;
}

.section-title {
    text-align: center;
    margin-bottom: 40px;
    color: #1a365d;
}

.timeline {
    position: relative;
    border-left: 2px solid #cbd5e0;
    margin-left: 20px;
    padding: 10px 0;
}

.timeline-item {
    position: relative;
    margin-bottom: 30px;
    padding-left: 30px;
}

.timeline-item::before {
    content: '';
    position: absolute;
    left: -9px;
    top: 5px;
    width: 16px;
    height: 16px;
    background: white;
    border: 2px solid #3182ce;
    border-radius: 50%;
}

.timeline-date {
    font-weight: bold;
    color: #3182ce;
    font-size: 0.9rem;
    margin-bottom: 5px;
}

.timeline-content {
    background: #fdfdfd;
    border: 1px solid #edf2f7;
    padding: 15px;
    border-radius: 8px;
}

.timeline-content h3 {
    margin: 0 0 8px 0;
    font-size: 1.1rem;
    color: #2d3748;
}

/* 現在の学びの強調 */
.timeline-item.current .timeline-content {
    border: 1px solid #3182ce;
    background: #ebf8ff;
}

.tag {
    background: #3182ce;
    color: #fff;
    padding: 2px 8px;
    border-radius: 4px;
    font-size: 0.75rem;
    display: inline-block;
    margin-bottom: 5px;
}

.timeline-content ul {
    margin: 10px 0 0;
    padding-left: 18px;
    font-size: 0.9rem;
}

/* 共通ナビゲーション（ボタン） */
.footer-nav {
    display: flex;
    justify-content: center;
    gap: 15px;
    margin-top: 40px;
    padding-top: 30px;
    border-top: 2px solid #f4f7f6;
}

.footer-nav .btn {
    text-decoration: none;
    padding: 12px 20px;
    border: 1px solid #1a365d;
    color: #1a365d;
    border-radius: 6px;
    font-weight: bold;
    font-size: 0.9rem;
    transition: 0.3s;
    text-align: center;
}

.footer-nav .btn:hover {
    background: #1a365d;
    color: #fff;
}

.footer-nav .btn.active {
    background: #e2e8f0;
    border-color: #cbd5e0;
    color: #718096;
    pointer-events: none;
}

/* スマホ対応 */
@media screen and (max-width: 768px) {
    .container {
        padding: 20px;
    }
    
    .footer-nav {
        flex-direction: column;
    }
    
    .footer-nav .btn {
        width: 100%;
    }
}