/* Expertise Section */
.expertise-section {
    padding: 80px 0;
}

.expertise-container {
    max-width: var(--container-max, 1140px);
    margin: 0 auto;
    padding: 0 20px;
}

.expertise-header {
    text-align: center;
    margin-bottom: 60px;
}

/* Overline */
.expertise-overline {
    display: inline-block;
    font-size: 13px;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 3px;
    color: var(--accent);
    margin-bottom: 10px;
}

.expertise-title {
    font-size: 38px;
    font-weight: 700;
    color: var(--text-primary);
    margin: 0 0 15px;
    text-transform: uppercase;
    letter-spacing: 1px;
}

.expertise-intro {
    font-size: 18px;
    color: var(--text-secondary);
    max-width: 700px;
    margin: 0 auto;
    line-height: 1.7;
}

/* ========================================
   EXPERTISE GRID — two columns on desktop
   ======================================== */

.expertise-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    align-items: start;
    gap: 16px;
}

/* ========================================
   EXPERTISE ITEM — accordion
   ======================================== */

.expertise-item {
    border: 1px solid var(--border-light);
    border-left: 3px solid var(--accent);
    background-color: var(--bg-white);
    transition: box-shadow 0.3s ease, border-color 0.3s ease;
}

@media (hover: hover) and (pointer: fine) {
    .expertise-item:hover {
        box-shadow: 0 4px 20px rgba(15, 34, 45, 0.08);
        border-color: var(--accent);
    }
}

.expertise-item.active {
    border-color: var(--accent);
    box-shadow: 0 4px 20px rgba(15, 34, 45, 0.08);
}

/* Item Header (button) */
.expertise-item-header {
    display: flex;
    align-items: center;
    gap: 15px;
    width: 100%;
    padding: 20px 22px;
    background: none;
    border: none;
    border-radius: 0;
    cursor: pointer;
    text-align: left;
    font-family: var(--font-primary);
    text-transform: none;
    letter-spacing: 0;
    color: var(--text-primary);
    transition: background-color 0.2s ease;
}

.expertise-item-header:hover {
    background-color: var(--bg-alt);
    transform: none;
}

.expertise-item-header:focus {
    outline: none;
    transform: none !important;
}

.expertise-item-header:focus-visible {
    outline: 2px solid var(--accent) !important;
    outline-offset: -2px !important;
}

/* Title */
.expertise-item-title {
    font-size: 16px;
    font-weight: 600;
    flex: 1;
    line-height: 1.3;
}

/* Arrow */
.expertise-item-arrow {
    flex-shrink: 0;
    color: var(--text-light);
    transition: transform 0.3s cubic-bezier(0.4, 0, 0.2, 1), color 0.3s ease;
}

.expertise-item.active .expertise-item-arrow {
    transform: rotate(180deg);
    color: var(--accent);
}

/* Item Body (expandable) */
.expertise-item-body {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.35s cubic-bezier(0.4, 0, 0.2, 1);
}

.expertise-item-body p {
    padding: 0 22px 22px;
    font-size: 15px;
    line-height: 1.8;
    color: var(--text-secondary);
    margin: 0;
}

/* ========================================
   RESPONSIVE
   ======================================== */

/* Tablet */
@media (max-width: 1024px) {
    .expertise-grid {
        grid-template-columns: 1fr;
        gap: 12px;
    }
}

/* Mobile */
@media (max-width: 768px) {
    .expertise-section {
        padding: 50px 0;
    }

    .expertise-header {
        margin-bottom: 40px;
    }

    .expertise-title {
        font-size: 30px;
    }

    .expertise-grid {
        gap: 10px;
    }

    .expertise-item-header {
        padding: 16px 16px;
        gap: 12px;
    }

    .expertise-item-title {
        font-size: 14px;
    }

    .expertise-item-body p {
        padding: 0 16px 16px;
        font-size: 14px;
    }
}