/* ══════════════════════════════════════════════════════════
   exams/exams.css — CSS trang DANH SÁCH đề thi
   Dùng cho: exams/index.html
   KHÔNG dùng cho trang làm bài → xem exams/style.css
   ══════════════════════════════════════════════════════════ */

/* ─── Section header ─── */
.exams-section-header {
  margin-bottom: 20px;
}
.exams-section-title {
  font-size: 1.15rem;
  font-weight: 800;
  color: var(--text);
  margin-bottom: 4px;
}
.exams-section-sub {
  font-size: .84rem;
  color: var(--text-3);
}

/* ─── Grid đề thi ─── */
/* Mobile: 2 cột */
.exam-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 12px;
}

/* ─── Card đề thi ─── */
.exam-card {
  background: var(--bg-card);
  border: 1.5px solid var(--border);
  border-radius: var(--radius);
  padding: 16px 14px;
  cursor: pointer;
  transition: var(--transition);
  box-shadow: var(--shadow-sm);
  display: flex;
  flex-direction: column;
  gap: 6px;
  position: relative;
  overflow: hidden;
  min-height: 148px;
  -webkit-tap-highlight-color: transparent;
}

/* Gạch màu đầu card */
.exam-card::before {
  content: '';
  position: absolute;
  top: 0; left: 0; right: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--primary), var(--primary-mid));
  transition: var(--transition);
}

/* Card paid — gạch xám */
.exam-card.paid::before {
  background: linear-gradient(90deg, #94a3b8, #cbd5e1);
}

/* Hover effect — chỉ trên desktop */
@media (hover: hover) {
  .exam-card:hover {
    transform: translateY(-3px);
    box-shadow: var(--shadow-md);
    border-color: var(--primary);
  }
  .exam-card.paid:hover {
    border-color: var(--warning);
  }
  .exam-card:hover::before {
    height: 4px;
  }
}

/* Active state — mobile tap feedback */
.exam-card:active {
  transform: scale(.98);
  box-shadow: var(--shadow-sm);
}

/* Số thứ tự */
.exam-card-num {
  font-size: 1.7rem;
  font-weight: 800;
  color: var(--border-2);
  line-height: 1;
}

/* Tiêu đề */
.exam-card-title {
  font-size: .9rem;
  font-weight: 700;
  color: var(--text);
  line-height: 1.35;
}

/* Meta (200 câu · 120 phút) */
.exam-card-meta {
  font-size: .74rem;
  color: var(--text-3);
  line-height: 1.4;
}

/* Best score */
.exam-card-best {
  font-size: .74rem;
  font-weight: 700;
  color: var(--success);
}

/* Footer card: badge action */
.exam-card-footer {
  margin-top: auto;
  padding-top: 6px;
}
.exam-card-btn {
  display: inline-flex;
  align-items: center;
  gap: 5px;
  padding: 5px 12px;
  border-radius: var(--radius-pill);
  font-size: .74rem;
  font-weight: 700;
  transition: var(--transition);
  white-space: nowrap;
}
.exam-card-btn.free {
  background: var(--primary-light);
  color: var(--primary);
}
.exam-card-btn.paid-lock {
  background: var(--bg);
  color: var(--text-3);
  border: 1px solid var(--border);
}
.exam-card-btn.coming-soon {
  background: var(--bg);
  color: var(--text-3);
  border: 1px dashed var(--border);
}

/* Hover trên btn (desktop) */
@media (hover: hover) {
  .exam-card:hover .exam-card-btn.free {
    background: var(--primary);
    color: #fff;
  }
  .exam-card:hover .exam-card-btn.paid-lock {
    background: var(--warning-light);
    color: var(--warning);
    border-color: var(--warning);
  }
}

/* ── Tablet ≥ 768px: 3 cột ── */
@media (min-width: 768px) {
  .exam-grid {
    grid-template-columns: repeat(3, 1fr);
    gap: 16px;
  }
  .exam-card {
    min-height: 168px;
    padding: 20px 18px;
  }
  .exam-card-num { font-size: 2rem; }
  .exam-card-title { font-size: .95rem; }
}

/* ── Desktop ≥ 1024px: 4 cột ── */
@media (min-width: 1024px) {
  .exam-grid {
    grid-template-columns: repeat(4, 1fr);
    gap: 18px;
  }
  .exam-card { min-height: 176px; padding: 22px 20px; }
}

/* ── Màn hình rất nhỏ < 360px: 1 cột ── */
@media (max-width: 359px) {
  .exam-grid { grid-template-columns: 1fr; }
}