:root {
    --android-green: #3ddc84;
    --dark-bg: #060708;
    --card-bg: rgba(255, 255, 255, 0.03);
    --glass-border: rgba(255, 255, 255, 0.1);
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Poppins', sans-serif;
}

body {
    background-color: var(--dark-bg);
    color: white;
    padding: 80px 20px;
    background-image: 
        radial-gradient(circle at 10% 20%, rgba(61, 220, 132, 0.05) 0%, transparent 40%),
        radial-gradient(circle at 90% 80%, rgba(61, 220, 132, 0.05) 0%, transparent 40%);

}

.timeline-header {
    text-align: center;
    margin-bottom: 100px;
}

.btn-back {
    color: var(--android-green);
    text-decoration: none;
    font-size: 0.8rem;
    letter-spacing: 2px;
    text-transform: uppercase;
    border: 1px solid var(--glass-border);
    padding: 10px 25px;
    border-radius: 50px;
    transition: 0.3s;
}

.btn-back:hover { background: var(--android-green); color: black; }

.timeline-header h1 {
    font-size: 3rem;
    margin-top: 30px;
    letter-spacing: -1px;
}

.green-text {
    color: var(--android-green);
    text-shadow: 0 0 20px rgba(61, 220, 132, 0.4);
}

/* CONTENEDOR ZIG-ZAG */
.timeline-container {
    position: relative;
    max-width: 1000px;
    margin: 0 auto;
}

/* Línea central sutil */
.timeline-container::after {
    content: '';
    position: absolute;
    width: 1px;
    background: linear-gradient(to bottom, transparent, var(--android-green), transparent);
    top: 0;
    bottom: 0;
    left: 50%;
    margin-left: -0.5px;
    opacity: 0.5;
}

.timeline-item {
    padding: 10px 50px;
    position: relative;
    width: 50%;
    margin-bottom: 30px;
}

.timeline-item:nth-child(odd) { left: 0; text-align: right; }
.timeline-item:nth-child(even) { left: 50%; text-align: left; }

/* El punto LED */
.timeline-dot {
    position: absolute;
    width: 12px;
    height: 12px;
    background-color: var(--android-green);
    border-radius: 50%;
    top: 50px;
    z-index: 10;
    box-shadow: 0 0 15px var(--android-green);
}

.timeline-item:nth-child(odd) .timeline-dot { right: -6px; }
.timeline-item:nth-child(even) .timeline-dot { left: -6px; }

.timeline-date {
    font-weight: 700;
    color: var(--android-green);
    margin-bottom: 10px;
    letter-spacing: 2px;
}


.timeline-content {
    background: var(--card-bg);
    backdrop-filter: blur(10px);
    border: 1px solid var(--glass-border);
    padding: 30px;
    border-radius: 20px;
    transition: all 0.4s ease;
}

.timeline-content:hover {
    border-color: rgba(61, 220, 132, 0.4);
    transform: translateY(-5px);
    background: rgba(255, 255, 255, 0.05);
}

.timeline-content h3 { font-size: 1.5rem; margin-bottom: 10px; }
.timeline-content p { color: rgba(255, 255, 255, 0.6); line-height: 1.6; }


@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.timeline-item {
    animation: fadeInUp 0.8s ease forwards;
}


.main-footer {
    margin-top: 100px;
    padding: 40px 20px;
    text-align: center;
    background: linear-gradient(to top, rgba(61, 220, 132, 0.05), transparent);
}

.footer-line {
    width: 100px;
    height: 1px;
    background: var(--android-green);
    margin: 0 auto 30px;
    opacity: 0.3;
}

.footer-content p {
    font-size: 0.8rem;
    color: rgba(255, 255, 255, 0.4);
    letter-spacing: 1px;
    margin-bottom: 20px;
}

.btn-home {
    display: inline-block;
    padding: 12px 30px;
    background: transparent;
    color: var(--android-green);
    border: 1px solid var(--android-green);
    border-radius: 50px;
    text-decoration: none;
    font-size: 0.9rem;
    font-weight: 600;
    transition: all 0.3s ease;
}

.btn-home:hover {
    background: var(--android-green);
    color: black;
    box-shadow: 0 0 20px rgba(61, 220, 132, 0.4);
    transform: translateY(-3px);
}

.timeline-img {
    width: 100%;
    max-width: 200px; 
    height: 120px; 
    object-fit: cover; 
    border-radius: 12px;
    margin-bottom: 15px;
    display: block;
    border: 1px solid rgba(255, 255, 255, 0.1);
    box-shadow: 0 4px 15px rgba(0,0,0,0.3);
}

.timeline-item:nth-child(odd) .timeline-img { margin-left: auto; }
.timeline-item:nth-child(even) .timeline-img { margin-right: auto; }


.timeline-logo, .timeline-img {
    width: 100%; 
    max-width: 120px; 
    border-radius: 12px;
    margin-bottom: 15px;
    display: block;
}

.timeline-item:nth-child(odd) .timeline-logo { margin-left: auto; } 
.timeline-item:nth-child(even) .timeline-logo { margin-right: auto; }