/**
 * PCTechComVn — Side Rail CSS
 * Child Theme CSS Module
 * Version: 1.0.0 (Sprint 0)
 *
 * Left side navigation rail: dots + badge + hotline.
 * Fixed position, chỉ hiện trên desktop ≥ 1100px.
 * JS: side-rail.js xử lý active state theo scroll.
 */

.side-rail {
  position: fixed;
  left: 0;
  top: 0;
  bottom: 0;
  width: var(--side-rail-w);
  background: linear-gradient(180deg, var(--blue-deeper), var(--blue-dark));
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 16px;
  z-index: var(--z-rail);
  padding: 20px 0;
}

.side-rail-badge {
  font-size: 0.55rem;
  font-weight: 800;
  color: var(--orange);
  text-align: center;
  line-height: 1.3;
  letter-spacing: 0.06em;
  margin-bottom: 12px;
}

.side-rail-dot {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.2);
  border: 2px solid transparent;
  cursor: pointer;
  transition: background var(--transition-fast),
              border-color var(--transition-fast),
              transform var(--transition-fast);
  position: relative;
  display: block;
  text-decoration: none;
}

.side-rail-dot:hover {
  background: rgba(255, 255, 255, 0.4);
  transform: scale(1.3);
}

.side-rail-dot.active {
  background: var(--orange);
  border-color: rgba(255, 255, 255, 0.5);
  transform: scale(1.3);
  box-shadow: 0 0 8px var(--orange-glow);
}

/* Tooltip label */
.side-rail-dot::after {
  content: attr(data-label);
  position: absolute;
  left: calc(100% + 14px);
  top: 50%;
  transform: translateY(-50%);
  background: var(--blue-deeper);
  color: var(--white);
  font-size: 0.72rem;
  font-weight: 600;
  padding: 4px 10px;
  border-radius: 6px;
  white-space: nowrap;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.2s;
}

.side-rail-dot:hover::after {
  opacity: 1;
}

.side-rail-hotline {
  font-size: 0.55rem;
  font-weight: 800;
  color: rgba(255, 255, 255, 0.6);
  writing-mode: vertical-lr;
  text-orientation: mixed;
  letter-spacing: 0.1em;
  margin-top: 16px;
}

/* Ẩn side rail trên tablet và mobile */
@media (max-width: 1100px) {
  .side-rail {
    display: none;
  }
}