/* --- Content Containers --- */
#education-content, 
#overview-content {
    transition: opacity 0.4s ease-in-out;
    max-width: 1200px;
    width: 100%;       /* Ensures it stretches to max-width */
    margin: 0 auto;    /* Centers the containers */
    box-sizing: border-box;
}

/* Specific state for Education */
#education-content {
    display: none;
    opacity: 0;
}

/* --- Navigation Buttons --- */
.section-nav {
    max-width: 1200px;
    margin: 0 auto 30px auto;
    width: 100%;
}

.nav-btn {
    padding: 12px 24px;
    border: 1px solid var(--sec-color-2);
    background: var(--sec-color);
    color: var(--white);
    cursor: pointer;
    border-radius: var(--border-radius);
    font-weight: 600;
    transition: var(--transition);
}

.nav-btn:hover {
    background: var(--sec-color-2);
    border-color: var(--green);
}

.nav-btn.active {
    background: var(--green);
    color: var(--bg-color);
    border-color: var(--green);
}

/* --- Language Cards --- */
.lang-item {
    background-color: var(--green);
    color: var(--bg-color); 
    border-radius: var(--border-radius);
    padding: 25px;
    margin-bottom: 20px;
    box-shadow: var(--shadow);
    transition: var(--transition);
    width: 100%;
    box-sizing: border-box;
}

.lang-item:hover {
    transform: translateY(-3px);
    box-shadow: 0 8px 15px rgba(0, 0, 0, 0.2);
}

.lang-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    width: 100%;
}

.lang-header strong {
    font-size: 1.5rem;
    letter-spacing: 0.5px;
}

/* --- Fold Button --- */
.fold-btn {
    background-color: var(--bg-color);
    color: var(--white);
    border: none;
    padding: 10px 20px;
    border-radius: 30px;
    font-size: 0.85rem;
    font-weight: 700;
    cursor: pointer;
    transition: var(--transition);
}

.fold-btn:hover {
    opacity: 0.85;
    transform: scale(1.05);
}

/* --- Nested Details --- */
.details {
    margin-top: 20px;
    padding-top: 20px;
    border-top: 1px solid rgba(16, 18, 23, 0.15);
}

.details h4 {
    margin: 15px 0 10px 0;
    font-size: 0.9rem;
    text-transform: uppercase;
    letter-spacing: 1.5px;
    font-weight: 800;
    opacity: 0.7;
}

.details ul {
    list-style: none;
    padding: 0;
    margin: 0;
}

.details li {
    color: var(--bg-color);
    padding: 6px 0;
    font-size: 1rem;
    border-bottom: 1px solid rgba(16, 18, 23, 0.05);
}

.details li:last-child {
    border-bottom: none;
}

.details a {
    color: var(--bg-color);
    text-decoration: none;
    font-weight: 600;
    border-bottom: 2px solid var(--bg-color);
    transition: opacity 0.2s;
}

.details a:hover {
    opacity: 0.6;
}

/* Ensure the bold label doesn't get the underline from the link */
.details li strong {
    font-weight: 700;
    margin-right: 5px;
    color: var(--bg-color)
}

/* Specific styling for the title link */
.details a {
    color: var(--bg-color);
    text-decoration: none;
    border-bottom: 1px solid var(--bg-color); /* Clean underline for title only */
    transition: opacity 0.2s;
}

.details a:hover {
    opacity: 0.6;
}

/* Header for the new Certificates section */
.details h4 {
    margin: 15px 0 8px 0;
    font-size: 0.85rem;
    text-transform: uppercase;
    letter-spacing: 1.2px;
    font-weight: 800;
    color: rgba(16, 18, 23, 0.7); /* Darker text for hierarchy */
}