/* Study Center Styles */

.study-tabs {
  display: flex;
  gap: 12px;
  padding: 24px;
  border-bottom: 1px solid var(--border);
  background: white;
  position: sticky;
  top: 0;
  z-index: 10;
}

.study-tab {
  padding: 10px 20px;
  border-radius: 50px;
  font-size: 14px;
  font-weight: 700;
  color: var(--text2);
  cursor: pointer;
  transition: all 0.2s;
  border: 1.5px solid var(--border);
}

.study-tab:hover { border-color: var(--accent); color: var(--accent); }
.study-tab.active { background: var(--accent); color: white; border-color: var(--accent); }

.study-tab-pane {
  padding: 32px;
  max-width: 1000px;
  margin: 0 auto;
}

.study-section { margin-bottom: 48px; }
.study-h3 { font-family: var(--font-d); font-size: 24px; font-weight: 800; color: var(--navy); margin-bottom: 20px; }

.study-tips {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 20px;
}

.study-tip-card {
  background: white;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 20px;
  box-shadow: var(--shadow-sm);
}

.study-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: 24px;
}

/* .faq-* → see global.css */

/* ── BAND DESCRIPTOR TABLES ── */
.band-desc-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 13px;
  line-height: 1.55;
  margin-bottom: 32px;
}
.band-desc-table th {
  background: #1e293b;
  color: #fff;
  padding: 10px 12px;
  text-align: left;
  font-size: 12px;
  font-weight: 700;
  position: sticky;
  top: 0;
}
.band-desc-table td {
  border: 1px solid #e0e0e0;
  padding: 10px 12px;
  vertical-align: top;
  color: #333;
}
.band-desc-table tbody tr:hover { background: #f8f8f8; }
.band-desc-table tbody tr.band-highlight { background: #e8f0fe; }
.band-num {
  font-size: 22px;
  font-weight: 800;
  text-align: center;
  vertical-align: middle;
}

/* ── VERB TENSES ── */
.tense-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 14px;
  margin-bottom: 24px;
}
.tense-table th, .tense-table td {
  border: 1px solid #ddd;
  padding: 10px 14px;
  text-align: left;
}
.tense-table th {
  background: #f5f0eb;
  font-weight: 700;
  color: #333;
  font-size: 13px;
}
.tense-table-overview td { font-style: italic; color: #555; }
.tense-time { font-weight: 700; font-style: normal !important; }

.tense-card {
  background: #fff;
  border: 1px solid #e0e0e0;
  border-radius: 6px;
  margin-bottom: 12px;
  overflow: hidden;
}
.tense-card-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 14px 18px;
  cursor: pointer;
  user-select: none;
}
.tense-card-header:hover { background: #fafafa; }
.tense-card-header h4 { margin: 0; font-size: 16px; color: #222; }
.tense-toggle { font-size: 20px; color: #999; font-weight: 300; }
.tense-card.open .tense-toggle { transform: rotate(45deg); }

.tense-card-body {
  display: none;
  padding: 0 18px 16px;
}
.tense-card.open .tense-card-body { display: block; }

.tense-row {
  display: flex;
  gap: 12px;
  padding: 7px 0;
  border-bottom: 1px solid #f0f0f0;
  font-size: 14px;
  line-height: 1.6;
  color: #333;
}
.tense-row:last-child { border-bottom: none; }
.tense-label {
  flex-shrink: 0;
  width: 100px;
  font-weight: 700;
  font-size: 12px;
  color: #888;
  text-transform: uppercase;
  padding-top: 2px;
}

/* ── TABLE HORIZONTAL SCROLL WRAPPER ── */
.band-desc-table-wrap,
.tense-table-wrap,
.score-table-wrap {
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
  margin-bottom: 24px;
}

/* ── RESPONSIVE DESIGN ── */
@media (max-width: 768px) {
  .study-tabs {
    padding: 12px;
    flex-wrap: wrap;
    gap: 8px;
    justify-content: center;
  }

  .study-tab {
    padding: 8px 14px;
    font-size: 12px;
    min-height: 44px;
    display: flex;
    align-items: center;
    justify-content: center;
  }

  .study-tab-pane {
    padding: 20px;
  }

  .study-tips, .study-grid {
    grid-template-columns: 1fr;
  }

  .band-desc-table {
    min-width: 600px;
  }

  .tense-table {
    min-width: 500px;
  }

  .tense-row {
    flex-wrap: wrap;
  }

  .tense-label {
    width: auto;
    flex-basis: 100%;
  }

  .study-h3 {
    font-size: 20px;
  }
}

@media (max-width: 480px) {
  .study-tabs {
    padding: 8px;
    gap: 6px;
  }

  .study-tab {
    padding: 6px 12px;
    font-size: 11px;
  }

  .study-tab-pane {
    padding: 16px;
  }

  .study-h3 {
    font-size: 18px;
  }

  .study-tip-card {
    padding: 16px;
  }

  .tense-card-header {
    padding: 12px 14px;
  }

  .tense-card-header h4 {
    font-size: 14px;
  }

  .tense-card-body {
    padding: 0 14px 14px;
  }

  .band-num {
    font-size: 18px;
  }
}