.content-area {
  display: flex;
  flex-direction: column;
  flex-grow: 1;
  overflow: hidden;
  position: relative;
  background-color: #ffffff;
}

/* 顶部固定表头层 (90px) */
.gantt-sticky-header {
  display: flex;
  height: 90px;
  flex-shrink: 0;
  background-color: #f8fafc;
  border-bottom: 2px solid var(--primary);
  z-index: 25;
  box-sizing: border-box;
}

.project-info-header {
  width: 575px;
  flex-shrink: 0;
  display: flex;
  align-items: flex-end;
  border-right: 2px solid #cbd5e1;
  background: linear-gradient(180deg, #f8fafc 0%, #f1f5f9 100%);
  box-sizing: border-box;
}

.project-info-header .col {
  height: 30px;
  font-weight: 700;
  color: #475569;
  font-size: 0.78rem;
  text-transform: uppercase;
  letter-spacing: 0.5px;
  background: transparent;
  padding: 0.5rem 0.6rem;
  border-right: 1px solid var(--border-color);
  display: flex;
  align-items: center;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
  box-sizing: border-box;
}

.gantt-header-container {
  flex-grow: 1;
  overflow: hidden;
  position: relative;
  background: linear-gradient(180deg, #f8fafc 0%, #f1f5f9 100%);
}

.gantt-header {
  display: flex;
  flex-direction: column;
  height: 90px;
  box-sizing: border-box;
}

.gantt-header .year-row, .gantt-header .month-row, .gantt-header .week-row {
  display: flex;
  height: 30px;
  box-sizing: border-box;
}

/* 主体统一滚动层 (单一原生垂直滚动，彻底消除左右对齐偏差) */
.gantt-scroll-body {
  display: flex;
  flex-grow: 1;
  overflow-x: auto;
  overflow-y: auto;
  position: relative;
  background-color: #ffffff;
}

.project-info-sticky {
  width: 575px;
  flex-shrink: 0;
  position: sticky;
  left: 0;
  z-index: 15;
  background-color: #ffffff;
  border-right: 2px solid #cbd5e1;
  box-shadow: 2px 0 8px rgba(0,0,0,0.05);
  min-height: 100%;
  background-image: 
    linear-gradient(to bottom, var(--border-color) 1px, transparent 1px),
    linear-gradient(to right, 
      transparent 39px, var(--border-color) 39px, var(--border-color) 40px,
      transparent 40px, transparent 119px, var(--border-color) 119px, var(--border-color) 120px,
      transparent 120px, transparent 314px, var(--border-color) 314px, var(--border-color) 315px,
      transparent 315px, transparent 384px, var(--border-color) 384px, var(--border-color) 385px,
      transparent 385px, transparent 439px, var(--border-color) 439px, var(--border-color) 440px,
      transparent 440px, transparent 494px, var(--border-color) 494px, var(--border-color) 495px,
      transparent 495px
    );
  background-size: 100% 40px, 100% 100%;
}

.col {
  padding: 0.5rem 0.6rem;
  font-size: 0.82rem;
  font-weight: 500;
  color: var(--text-main);
  border-right: 1px solid var(--border-color);
  height: 100%;
  display: flex;
  align-items: center;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
  box-sizing: border-box;
}

.col-no { width: 40px; flex-shrink: 0; justify-content: center; color: #64748b; font-weight: 600; font-size: 0.78rem; }
.col-region { width: 80px; flex-shrink: 0; }
.col-operator { width: 195px; flex-shrink: 0; font-weight: 600; color: #0f172a; }
.col-period { width: 70px; flex-shrink: 0; color: #0284c7; font-weight: 600; }
.col-dvt { width: 55px; flex-shrink: 0; justify-content: center; color: #475569; }
.col-pvt { width: 55px; flex-shrink: 0; justify-content: center; color: #475569; }
.col-fee { width: 80px; flex-shrink: 0; justify-content: center; border-right: none; color: #059669; font-weight: 600; font-size: 0.8rem; }

.data-row {
  display: flex;
  height: 40px;
  align-items: center;
  border-bottom: 1px solid var(--border-color);
  transition: background-color 0.15s, border-left 0.15s;
  cursor: pointer;
  box-sizing: border-box;
  border-left: 3px solid transparent;
  background-color: #ffffff;
}

/* Zebra striping for MS Project Table */
.data-row:nth-child(even) {
  background-color: #f8fafc;
}

.data-row:hover {
  background-color: #f1f5f9;
}

.data-row.selected {
  background-color: #bae6fd !important;
  border-left: 4px solid #0284c7 !important;
  font-weight: 600;
}

.data-row.selected .col-no {
  background-color: #0284c7 !important;
  color: #ffffff !important;
  font-weight: 700;
  border-radius: 2px;
}

.gantt-row.selected {
  background-color: rgba(186, 230, 253, 0.45) !important;
  border-bottom: 1px solid #38bdf8 !important;
}

.gantt-body-container {
  flex-grow: 1;
  position: relative;
  min-height: 100%;
}

.header-cell {
  min-width: var(--cell-width, 40px);
  flex-shrink: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.75rem;
  border-right: 1px solid var(--border-color);
  color: #475569;
  box-sizing: border-box;
}

.year-cell, .month-cell {
  font-weight: 700;
  background-color: rgba(0,0,0,0.02);
  color: #1e293b;
  letter-spacing: 0.3px;
}

.week-cell {
  background-color: rgba(0, 0, 0, 0.01);
  transition: background-color 0.15s, color 0.15s;
  cursor: pointer;
  font-weight: 500;
}

.week-cell:hover {
  background-color: var(--primary);
  color: #ffffff;
  font-weight: 700;
}

.data-rows {
  background-image: linear-gradient(to bottom, var(--border-color) 1px, transparent 1px);
  background-size: 100% 40px;
}

.gantt-body {
  position: relative;
  min-height: 100%;
  background-image: linear-gradient(to right, rgba(0, 0, 0, 0.05) 1px, transparent 1px), linear-gradient(to bottom, var(--border-color) 1px, transparent 1px);
  background-size: var(--cell-width, 40px) 40px, 100% 40px;
  background-color: #ffffff;
}

.gantt-row {
  display: flex;
  height: 40px;
  border-bottom: 1px solid var(--border-color);
  position: relative;
  box-sizing: border-box;
  transition: background-color 0.15s;
}

.gantt-row:nth-child(even) {
  background-color: rgba(248, 250, 252, 0.8);
}

.gantt-row:hover {
  background-color: rgba(224, 242, 254, 0.5);
}

.phase-block {
  position: absolute;
  top: 4px;
  height: 22px;
  border-radius: 4px;
  display: flex;
  align-items: center;
  justify-content: flex-start;
  padding: 0 6px;
  font-size: 0.72rem;
  font-weight: 600;
  color: #ffffff;
  cursor: pointer;
  transition: all 0.18s ease-in-out;
  overflow: hidden;
  white-space: nowrap;
  box-shadow: 0 1px 4px rgba(0,0,0,0.15);
  border-top: 1px solid rgba(255,255,255,0.3);
  border-bottom: 1px solid rgba(0,0,0,0.15);
  box-sizing: border-box;
  z-index: 5;
}

.phase-block:hover {
  filter: brightness(1.1);
  transform: translateY(-1px) scale(1.01);
  box-shadow: 0 4px 10px rgba(0,0,0,0.25);
  z-index: 20 !important;
}

.phase-block.dhl {
  top: 27px;
  height: 9px;
  border-radius: 3px;
  font-size: 0.58rem;
  line-height: 9px;
  padding: 0 4px;
  box-shadow: 0 1px 3px rgba(0,0,0,0.2);
  z-index: 12;
}

.phase-block.ready { background: var(--phase-ready); }
.phase-block.iv { background: var(--phase-iv); }
.phase-block.iv-pass { background: var(--phase-iv-pass); }
.phase-block.fixing { background: var(--phase-fixing); }
.phase-block.dhl { background: var(--phase-dhl); }
.phase-block.official { background: var(--phase-official); }
.phase-block.pass { background: var(--phase-pass); }

.today-line {
  position: absolute;
  top: 0;
  bottom: 0;
  width: 2px;
  background-color: #dc2626;
  box-shadow: 0 0 6px rgba(220, 38, 38, 0.4);
  z-index: 12;
  pointer-events: none;
}

.today-line::before {
  content: 'TODAY';
  position: absolute;
  top: 2px;
  left: -18px;
  background-color: #dc2626;
  color: #ffffff;
  font-size: 0.6rem;
  font-weight: 700;
  padding: 1px 4px;
  border-radius: 3px;
  letter-spacing: 0.5px;
  box-shadow: 0 2px 4px rgba(0,0,0,0.2);
}

.phase-tooltip {
  position: absolute;
  background: #0f172a;
  border: 1px solid #334155;
  border-radius: 6px;
  padding: 0.5rem 0.75rem;
  font-size: 0.8rem;
  color: #ffffff;
  z-index: 100;
  pointer-events: none;
  box-shadow: 0 10px 25px rgba(0,0,0,0.25);
  backdrop-filter: blur(4px);
  display: none;
  white-space: nowrap;
}