/* ===== 全局 ===== */
* { margin: 0; padding: 0; box-sizing: border-box; }
body {
  font-family: "Microsoft YaHei", "PingFang SC", "Segoe UI", Arial, sans-serif;
  color: #2d3748;
  background: #f4f6f9;
  line-height: 1.8;
}

/* ===== 页头（深空背景 + 琥珀金渐变） ===== */
header {
  background: 
    linear-gradient(135deg, rgba(10, 14, 26, 0.4) 0%, rgba(13, 17, 23, 0.15) 60%, rgba(5, 7, 15, 0.35) 100%),
    url("banner.jpg") no-repeat center center;
  background-size: cover;
  color: #fff;
  text-align: center;
  padding: 34px 20px 28px;
  position: relative;
  box-shadow: inset 0 -3px 12px rgba(0, 0, 0, 0.5);
}

.header-inner {
  max-width: 1000px;
  margin: 0 auto;
}

header h1 {
  font-size: 2.35em;
  letter-spacing: 4px;
  margin-bottom: 6px;
  font-weight: 800;
  background: linear-gradient(90deg, #ffffff 10%, #ffd699 50%, #f59e0b 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  filter: drop-shadow(0 2px 10px rgba(0, 0, 0, 0.9));
}

.subtitle {
  font-size: 1.05em;
  color: #fce7cf;
  letter-spacing: 1.5px;
  margin-top: 4px;
  text-shadow: 0 1px 5px rgba(0, 0, 0, 0.9);
}

.subtitle-en {
  font-size: 0.9em;
  color: #d1d5db;
  font-style: italic;
  letter-spacing: 0.8px;
  margin-top: 2px;
  text-shadow: 0 1px 4px rgba(0, 0, 0, 0.9);
}

/* ===== 导航栏（曜石黑底 + 吸积盘暖金指示器） ===== */
nav {
  background: #0d131f; /* 深空曜石黑，与星空背景浑然一体 */
  position: sticky;
  top: 0;
  z-index: 100;
  box-shadow: 0 3px 10px rgba(0, 0, 0, 0.25);
  border-bottom: 1px solid rgba(245, 158, 11, 0.2);
}
nav ul {
  display: flex;
  justify-content: center;
  flex-wrap: wrap;
  list-style: none;
  max-width: 1100px;
  margin: 0 auto;
}
nav li a {
  display: block;
  padding: 13px 20px;
  color: #e2e8f0;
  text-decoration: none;
  font-size: 0.95em;
  font-weight: 500;
  transition: all 0.25s ease;
  border-bottom: 3px solid transparent;
}
nav li a:hover {
  color: #d58b0b;
  background: rgba(255, 255, 255, 0.05);
}
nav li a.active {
  color: #d58b0b;
  font-weight: 700;
  border-bottom: 3px solid #d58b0b; /* 底部暖金光条高亮 */
  background: rgba(245, 158, 11, 0.08);
}

/* ===== 主体内容区 ===== */
main {
  max-width: 1000px;
  margin: 30px auto;
  padding: 0 20px;
}
section {
  background: #ffffff;
  border-radius: 8px;
  padding: 30px 35px;
  margin-bottom: 25px;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.05);
  border: 1px solid #e5e7eb;
}
h2 {
  font-size: 1.45em;
  color: #111827;
  border-left: 5px solid #d97706; /* 标题采用暖金实线 */
  padding-left: 14px;
  margin-bottom: 20px;
}
h3 {
  font-size: 1.15em;
  color: #9a3412;
  margin: 18px 0 10px;
}
p { margin-bottom: 12px; text-align: justify; }

/* ===== 重要日期框（微暖金质感，弱化刺眼感） ===== */
.highlight-box {
  background: linear-gradient(135deg, #fef3c7 0%, #fae8d4 100%);
  border-left: 6px solid #d97706;
  border-radius: 6px;
  padding: 20px 28px;
}
.highlight-box h3 {
  color: #92400e;
  font-size: 1.18em;
  margin-bottom: 8px;
}
.highlight-box p {
  font-size: 1.02em;
  color: #78350f;
  margin-bottom: 4px;
  font-weight: 500;
}

/* ===== 表格 ===== */
.simple-table,
.committee-table {
  width: 100%;
  border-collapse: collapse;
  margin: 15px 0;
}
.simple-table th,
.simple-table td,
.committee-table td {
  border: 1px solid #e5e7eb;
  padding: 10px 14px;
  text-align: left;
  font-size: 0.95em;
}
.simple-table th {
  background: #f8fafc;
  color: #1f2937;
  font-weight: 600;
  border-bottom: 2px solid #cbd5e1;
}
.committee-table tr:nth-child(even) {
  background: #f9fafb;
}
.committee-table td:first-child {
  font-weight: 600;
  width: 40%;
  color: #9a3412;
}

/* ===== 日程表（沉浸深色表头） ===== */
.schedule-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.88em;
  margin: 15px 0;
}
.schedule-table th {
  background: #0d131f; /* 表头统一为深空曜黑 */
  color: #fef3c7;       /* 表头文字为淡淡的暖金色 */
  padding: 12px 8px;
  text-align: center;
  font-weight: 600;
  line-height: 1.5;
  border: 1px solid #1f2937;
}
.schedule-table td {
  border: 1px solid #e5e7eb;
  padding: 9px 10px;
  text-align: center;
  vertical-align: middle;
}
.schedule-table tr:nth-child(even) {
  background: #fafafa;
}
.schedule-table tr:hover {
  background: #fffbeb; /* 鼠标划过微泛暖金 */
}

/* ===== 报告人卡片 ===== */
.session-card {
  background: #fff;
  border: 1px solid #e5e7eb;
  border-left: 5px solid #d97706;
  border-radius: 6px;
  padding: 18px 24px;
  margin-bottom: 18px;
  box-shadow: 0 1px 3px rgba(0,0,0,0.03);
}
.session-card h3 {
  margin-top: 0;
  color: #9a3412;
  font-size: 1.1em;
}
.session-card ul {
  list-style: none;
  padding-left: 0;
}
.session-card li {
  padding: 6px 0;
  border-bottom: 1px dashed #f3f4f6;
}
.session-card li:last-child { border-bottom: none; }
.session-card strong { color: #1f2937; }

/* ===== 页脚 ===== */
footer {
  background: #0d131f; /* 底部与导航栏呼应，稳重大气 */
  color: rgba(255, 255, 255, 0.65);
  text-align: center;
  padding: 26px 20px;
  font-size: 0.88em;
  margin-top: 40px;
  border-top: 1px solid rgba(245, 158, 11, 0.2);
}
footer p { margin-bottom: 4px; }

/* ===== 响应式 ===== */
@media (max-width: 768px) {
  header h1 { font-size: 1.6em; }
  nav li a { padding: 10px 12px; font-size: 0.85em; }
  main { padding: 0 10px; }
  section { padding: 20px 16px; }
  .schedule-table { font-size: 0.75em; }
  .schedule-table th,
  .schedule-table td { padding: 6px 4px; }
}