/* ================================================================
 * DATEI: css/components/icon-rail.css
 * ZWECK: Vertikale Icon-Navigation (linke Seite)
 * Aesthetic: Refined Brass Studio
 * ================================================================ */

.icon-rail {
    width: var(--rail-width);
    background: var(--bg-surface);
    border-right: 1px solid var(--border-subtle);
    display: flex;
    flex-direction: column;
    justify-content: space-between;
    align-items: center;
    padding: var(--space-3) 0 var(--space-4);
    flex-shrink: 0;
    z-index: 200;
    position: relative;
}

.icon-rail::after {
    content: '';
    position: absolute;
    top: 0;
    right: -1px;
    bottom: 0;
    width: 1px;
    background: linear-gradient(
        to bottom,
        transparent,
        var(--accent-primary-transparent) 30%,
        var(--accent-primary-transparent) 70%,
        transparent
    );
    opacity: 0.5;
    pointer-events: none;
}

.icon-rail-top {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: var(--space-5);
}

.icon-rail-logo {
    padding-bottom: var(--space-3);
    border-bottom: 1px solid var(--border-subtle);
    width: 36px;
    display: flex;
    justify-content: center;
}

.logo-mark {
    width: 30px;
    height: 30px;
    background: linear-gradient(145deg, var(--brass), var(--brass-dark));
    border-radius: var(--radius-sm);
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 800;
    font-size: var(--font-sm);
    color: var(--text-on-accent);
    letter-spacing: 0;
    box-shadow: 0 2px 8px rgba(201, 168, 124, 0.25);
    transition: transform var(--transition-normal), box-shadow var(--transition-normal);
}

.logo-mark:hover {
    transform: scale(1.05);
    box-shadow: 0 4px 12px rgba(201, 168, 124, 0.35);
}

.icon-rail-nav {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: var(--space-1);
}

.icon-rail-bottom {
    display: flex;
    flex-direction: column;
    align-items: center;
}

/* ===== RAIL ITEM ===== */
.rail-item {
    width: 38px;
    height: 38px;
    border: none;
    background: transparent;
    color: var(--text-muted);
    border-radius: var(--radius-md);
    cursor: pointer;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    font-size: 1rem;
    transition: all var(--transition-normal);
    position: relative;
    gap: 1px;
}

.rail-item .rail-label {
    font-size: 0.5625rem;
    font-weight: 600;
    letter-spacing: 0.01em;
    opacity: 0.85;
    line-height: 1;
    white-space: nowrap;
}

.rail-item i {
    font-size: 0.95rem;
    transition: transform var(--transition-normal);
}

.rail-item:hover {
    background: var(--bg-hover);
    color: var(--text-secondary);
}

.rail-item:hover i {
    transform: scale(1.08);
}

.rail-item.active {
    background: var(--accent-primary-transparent);
    color: var(--accent-primary);
}

.rail-item.active::before {
    content: '';
    position: absolute;
    left: -7px;
    top: 50%;
    transform: translateY(-50%);
    width: 3px;
    height: 20px;
    background: var(--accent-primary);
    border-radius: 0 3px 3px 0;
}

/* ===== TOOLTIP (optional, only on hover without label) ===== */
.rail-item[title]::after {
    content: attr(title);
    position: absolute;
    left: calc(100% + 12px);
    top: 50%;
    transform: translateY(-50%) translateX(-4px);
    background: var(--bg-elevated);
    color: var(--text-primary);
    padding: var(--space-1) var(--space-3);
    border-radius: var(--radius-sm);
    font-size: var(--font-xs);
    font-weight: 500;
    white-space: nowrap;
    opacity: 0;
    pointer-events: none;
    transition: opacity var(--transition-fast), transform var(--transition-fast);
    box-shadow: var(--shadow-md);
    border: 1px solid var(--border-subtle);
    z-index: 300;
    display: none; /* hidden when labels are shown */
}