/* =========================================================
 * 明佑司典 · 题库中心（统一美观版）
 * ======================================================= */
* { box-sizing: border-box; }
:root {
  --primary: #0d9488;
  --primary-light: #5eead4;
  --primary-dark: #0f766e;
  --primary-bg: #f0fdfa;
  --navy: #16324f;
  --ink: #1e293b;
  --muted: #64748b;
  --faint: #94a3b8;
  --line: #e2e8f0;
  --bg: #f6fbfa;
  --card-bg: #ffffff;
  --radius: 16px;
  --shadow-sm: 0 2px 8px rgba(22,50,79,.04);
  --shadow-md: 0 4px 20px rgba(22,50,79,.07);
  --shadow-lg: 0 12px 36px rgba(13,148,136,.12);
}
body {
  margin: 0; background: var(--bg);
  font-family: "Source Han Sans SC", "Noto Sans SC", "Microsoft YaHei", sans-serif;
  color: var(--ink); line-height: 1.6;
}
h1, h2, h3, .bank-head-left h1, .year-title {
  font-family: "Noto Serif SC", "Source Han Serif SC", "SimSun", serif;
}

/* ---------- 顶部导航（毛玻璃吸顶，同门户风格） ---------- */
.top-nav {
  position: sticky; top: 0; z-index: 100;
  background: rgba(255,255,255,.72);
  backdrop-filter: blur(18px); -webkit-backdrop-filter: blur(18px);
  border-bottom: 1px solid #e5eaf3;
  transition: all .3s ease;
}
.top-nav.scrolled { background: rgba(255,255,255,.92); border-bottom-color: #d1dce6; box-shadow: 0 4px 20px rgba(22,50,79,.06); }
.top-nav-inner { max-width: 1200px; margin: 0 auto; padding: 0 24px; height: 72px; display: flex; align-items: center; gap: 32px; }
.brand { display: flex; align-items: center; gap: 12px; text-decoration: none; }
.brand-logo { width: 38px; height: 38px; border-radius: 50%; border: 2px solid #fff; box-shadow: 0 2px 6px rgba(0,0,0,.15); }
.brand-name { font-weight: 800; color: var(--navy); font-size: 1.15rem; letter-spacing: 1px; }
.top-links { display: flex; gap: 28px; margin-left: auto; }
.top-links a {
  position: relative; padding: 6px 0; color: var(--ink); text-decoration: none; font-size: .95rem;
  display: inline-flex; align-items: center; gap: 5px; transition: color .2s;
}
.top-links a:hover { color: var(--primary); }
.top-links a.active { color: var(--primary); font-weight: 700; }
.top-links a.active::after { content: ""; position: absolute; left: 0; right: 0; bottom: -2px; height: 3px; border-radius: 3px; background: linear-gradient(90deg, var(--primary-light), var(--primary)); }

/* ---------- 题库中心头部 ---------- */
.bank-wrap { max-width: 1200px; margin: 0 auto; padding: 36px 20px 80px; }
.bank-head { display: flex; justify-content: space-between; gap: 24px; margin-bottom: 32px; flex-wrap: wrap; }
.bank-head-left h1 { font-size: 2rem; margin: 0 0 6px; color: var(--navy); letter-spacing: 1px; }
.bank-head-left h1 + p { color: var(--muted); font-size: .92rem; margin: 0 0 18px; }

.big-tabs {
  display: inline-flex; background: #eef2f8; border-radius: 12px; padding: 5px; margin-bottom: 16px;
  box-shadow: inset 0 1px 3px rgba(22,50,79,.06);
}
.big-tab {
  border: none; background: transparent; padding: 9px 38px; border-radius: 9px;
  font-size: .98rem; color: var(--muted); cursor: pointer; font-weight: 600;
  transition: all .25s;
}
.big-tab:hover:not(.active) { color: var(--ink); }
.big-tab.active {
  background: var(--primary); color: #fff;
  box-shadow: 0 3px 12px rgba(13,148,136,.35);
}

.sub-tabs { display: flex; gap: 22px; font-size: .92rem; }
.sub-tab { color: var(--muted); cursor: pointer; padding-bottom: 4px; transition: color .2s; }
.sub-tab:hover:not(.disabled) { color: var(--primary); }
.sub-tab.active { color: var(--primary); font-weight: 700; border-bottom: 2px solid var(--primary); }
.sub-tab.disabled { color: #b6c2d4; cursor: not-allowed; }

/* 倒计时卡片 */
.countdown-card {
  background: linear-gradient(135deg, #fff 0%, var(--primary-bg) 100%);
  border-radius: var(--radius); padding: 18px 22px; min-width: 260px;
  box-shadow: var(--shadow-md); border: 1px solid #d1e8e4; align-self: flex-start;
  position: relative; overflow: hidden;
}
.countdown-card::before {
  content: ""; position: absolute; top: -30px; right: -30px;
  width: 100px; height: 100px; border-radius: 50%;
  background: radial-gradient(circle, rgba(13,148,136,.08), transparent 70%);
}
.cd-title { font-size: .92rem; font-weight: 700; color: var(--navy); text-align: center; margin-bottom: 12px; }
.cd-body { display: flex; align-items: center; gap: 14px; }
.cd-mascot { width: 48px; height: 48px; border-radius: 50%; box-shadow: 0 2px 8px rgba(0,0,0,.1); }
.cd-info { font-size: .8rem; color: var(--muted); line-height: 1.5; flex: 1; }
.cd-days { text-align: center; }
.cd-days b { font-size: 2.4rem; color: #f97316; font-weight: 800; line-height: 1; }
.cd-days span { color: #f97316; font-size: .88rem; margin-left: 3px; }

/* ---------- 年份区块 ---------- */
.year-section { margin-bottom: 36px; }
.year-title {
  font-size: 1.35rem; color: var(--navy); margin: 0 0 16px; font-weight: 800;
  display: flex; align-items: center; gap: 10px;
}
.year-title::before {
  content: ""; width: 4px; height: 24px; border-radius: 2px;
  background: linear-gradient(180deg, var(--primary), var(--primary-light));
}

.paper-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 20px; }
@media (max-width: 900px) { .paper-grid { grid-template-columns: 1fr; } }

/* ---------- 试卷卡片 ---------- */
.paper-card {
  background: var(--card-bg); border-radius: var(--radius); padding: 24px 26px;
  border: 1px solid #e8edf4; box-shadow: var(--shadow-sm);
  transition: box-shadow .3s, transform .3s, border-color .3s;
  position: relative; overflow: hidden;
}
.paper-card::before {
  content: ""; position: absolute; top: 0; left: 0; right: 0; height: 3px;
  background: linear-gradient(90deg, var(--primary), var(--primary-light));
  opacity: 0; transition: opacity .3s;
}
.paper-card:hover {
  box-shadow: var(--shadow-lg); transform: translateY(-3px);
  border-color: #b8e4de;
}
.paper-card:hover::before { opacity: 1; }

.pc-top { display: flex; justify-content: space-between; align-items: flex-start; margin-bottom: 16px; }
.pc-name { font-weight: 800; color: var(--primary-dark); font-size: 1.08rem; }
.pc-sub { font-size: .78rem; color: var(--faint); margin-top: 4px; }
.pc-status {
  font-size: .76rem; color: var(--faint); background: #f1f5f9;
  padding: 4px 12px; border-radius: 999px; font-weight: 500;
  transition: all .2s;
}
.pc-status.started { color: var(--primary); background: var(--primary-bg); }

.pc-stats {
  display: grid; grid-template-columns: 1fr 1fr 1fr; gap: 8px;
  background: linear-gradient(135deg, #f8fdfb 0%, #f0f7f5 100%);
  border-radius: 12px; padding: 16px 10px; margin-bottom: 16px;
  border: 1px solid #e8f3f0;
}
.pc-stat { text-align: center; }
.pc-stat i { font-style: normal; font-size: 1.15rem; display: block; }
.pc-stat span { font-size: .74rem; color: var(--faint); display: block; margin: 3px 0; }
.pc-stat b { font-size: 1.1rem; color: var(--primary-dark); }

.pc-progress { display: flex; justify-content: space-between; font-size: .82rem; color: var(--muted); margin-bottom: 7px; }
.pc-progress b { color: var(--primary); }
.pc-bar { height: 7px; background: #eef2f8; border-radius: 999px; overflow: hidden; margin-bottom: 18px; }
.pc-bar-in {
  height: 100%; border-radius: 999px;
  background: linear-gradient(90deg, var(--primary), var(--primary-light));
  transition: width .5s ease;
}

.pc-foot { display: flex; justify-content: space-between; align-items: center; gap: 10px; flex-wrap: wrap; }
.count-chips { display: flex; align-items: center; gap: 7px; flex-wrap: wrap; }
.chip-label { font-size: .8rem; color: var(--faint); margin-right: 4px; }
.chip {
  border: 1.5px solid #dbe3ef; background: #fff; color: var(--muted);
  border-radius: 8px; padding: 6px 14px; font-size: .82rem; cursor: pointer;
  transition: all .18s;
}
.chip:hover { border-color: var(--primary); color: var(--primary); }
.chip.active {
  background: var(--primary); border-color: var(--primary); color: #fff;
  box-shadow: 0 2px 8px rgba(13,148,136,.25);
}

.btn-start {
  border: none; background: linear-gradient(135deg, var(--primary) 0%, var(--primary-dark) 100%);
  color: #fff; border-radius: 10px; padding: 11px 26px; font-size: .92rem;
  font-weight: 700; cursor: pointer; box-shadow: 0 4px 14px rgba(13,148,136,.3);
  transition: all .2s;
}
.btn-start:hover { box-shadow: 0 6px 20px rgba(13,148,136,.4); transform: translateY(-1px); }
.btn-start:active { transform: translateY(0); }

/* toast */
.toast {
  position: fixed; bottom: 40px; left: 50%; transform: translateX(-50%);
  background: var(--navy); color: #fff; padding: 14px 28px; border-radius: 12px;
  font-size: .9rem; z-index: 9999; box-shadow: 0 8px 24px rgba(0,0,0,.2);
  animation: toastIn .3s ease;
}
@keyframes toastIn { from { opacity: 0; transform: translate(-50%, 10px); } to { opacity: 1; transform: translate(-50%, 0); } }