/* --- GENEL AYARLAR --- */
.tarihce-section {
    padding: 80px 0;
    background-color: #ffffff;
    font-family: 'Roboto', sans-serif;
    text-align: center;
}

.tarihce-baslik-alani {
    margin-bottom: 70px;
}

.tarihce-baslik-alani h2 {
    font-size: clamp(32px, 5vw, 42px);
    font-weight: 800;
    color: #111827;
    margin-bottom: 10px;
}

.yillar-ozet {
    font-size: 15px;
    color: #6b7280;
    letter-spacing: 2px;
}

/* --- ORTA ÇİZGİ VE YÖN BUTONLARI --- */
.timeline-container {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 20px;
    margin-bottom: 50px;
    max-width: 900px;
    margin-left: auto;
    margin-right: auto;
}

.nav-btn {
    background: #ffffff;
    border: 1px solid #d1d5db;
    border-radius: 14px;
    width: 50px;
    height: 50px;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    color: #374151;
    font-size: 18px;
    transition: all 0.3s ease;
    flex-shrink: 0;
}

.nav-btn:hover {
    background: #f3f4f6;
    border-color: #9ca3af;
}

/* --- TARİHÇE NOKTALARI --- */
.timeline-track-wrapper {
    position: relative;
    flex: 1;
    display: flex;
    align-items: center;
    height: 100px; /* Aktif balonun sığması için yükseklik */
}

.timeline-track {
    position: absolute;
    top: 50%;
    left: 0;
    right: 0;
    height: 1px;
    background-color: #cbd5e1;
    transform: translateY(-50%);
    z-index: 1;
}

.timeline-points {
    position: relative;
    z-index: 2;
    display: flex;
    justify-content: space-between;
    width: 100%;
    align-items: center;
}

.timeline-point {
    display: flex;
    flex-direction: column;
    align-items: center;
    cursor: pointer;
    position: relative;
}

/* Pasif Yıl Yazısı (Üstte) */
.yil-text {
    position: absolute;
    top: -35px;
    font-size: 14px;
    color: #4b5563;
    transition: opacity 0.3s;
}

/* Pasif Nokta (Küçük Halka) */
.dot {
    width: 20px;
    height: 20px;
    border-radius: 50%;
    background-color: #ffffff;
    border: 2px solid #3b82f6; /* Mavi çerçeve */
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
}

.dot-yil {
    display: none;
    color: #ffffff;
    font-weight: 700;
    font-size: 18px;
}

/* AKTİF DURUM (Görseldeki Mavi Balon) */
.timeline-point.active .yil-text {
    opacity: 0; /* Üstteki yazıyı gizle (Çünkü balonun içine yazılacak) */
}

.timeline-point.active .dot {
    width: 90px;
    height: 90px;
    background-color: #3b82f6;
    border: none;
    /* Görseldeki Mavi Parlama Efekti (Glow) */
    box-shadow: 0 15px 35px -5px rgba(59, 130, 246, 0.6); 
}

.timeline-point.active .dot-yil {
    display: block; /* İçindeki yılı göster */
}

/* --- DEĞİŞEN METİN ALANI --- */
.timeline-content-wrapper {
    position: relative;
    max-width: 650px;
    margin: 0 auto;
    min-height: 100px;
}

.timeline-content {
    display: none;
    /* Metin değişirken yumuşak geçiş animasyonu */
    animation: fadeIn 0.5s ease forwards; 
}

.timeline-content.active {
    display: block;
}

.timeline-content p {
    font-size: 17px;
    color: #4b5563;
    line-height: 1.6;
    margin: 0;
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(15px); }
    to { opacity: 1; transform: translateY(0); }
}

/* --- MOBİL UYUMLULUK --- */
@media (max-width: 768px) {
    .timeline-container { gap: 10px; }
    .nav-btn { width: 40px; height: 40px; font-size: 14px; }
    .timeline-point.active .dot { width: 70px; height: 70px; }
    .timeline-point.active .dot-yil { font-size: 14px; }
    .yil-text { font-size: 12px; }
}