.subject-page .page { width: min(100% - 32px, 620px); padding-top: 28px; }
.subject-page .site-header { display: none; }
.subject-page .back-link { display: inline-flex; align-items: center; gap: 9px; color: #167eea; font-size: 17px; font-weight: 800; margin-bottom: 34px; min-height: 44px; }
.subject-page .back-link span { font-size: 26px; line-height: 1; }
.subject-page .subject-intro { display: grid; grid-template-columns: minmax(0, 1fr) 108px; gap: 0 12px; align-items: center; max-width: none; margin: 0 0 42px; }
.subject-page .subject-intro h1 { grid-column: 1; grid-row: 1; align-self: end; margin: 0 0 7px; color: #142333; font-size: clamp(46px, 10vw, 62px); line-height: 1; }
.subject-page .subject-intro p { grid-column: 1; grid-row: 2; align-self: start; color: #637387; font-size: 17px; line-height: 1.5; }
.subject-page .subject-header-art { grid-column: 2; grid-row: 1 / 3; width: 108px; height: 108px; object-fit: contain; animation: subject-pop 260ms cubic-bezier(0.23, 1, 0.32, 1) both; }
.subject-page .subject-section { margin-top: 0; }
.subject-page .subject-section + .subject-section { margin-top: 42px; }
.subject-page .subject-section h2 { margin: 0 0 16px; color: #2c3a48; font-size: 21px; font-weight: 900; }
.subject-page .variant-card { display: grid; grid-template-columns: 23px minmax(0, 1fr) 64px; gap: 10px 12px; align-items: center; min-height: 166px; padding: 20px; border: 0; border-radius: 22px; background: linear-gradient(130deg, #efffe6, #e1fbd4); box-shadow: 0 5px 0 #b9e5a5; }
.subject-page .variant-card:first-child { background: linear-gradient(130deg, #efffe6, #e1fbd4); border: 0; box-shadow: 0 5px 0 #b9e5a5; }
.subject-page .variant-card .exam-arrow { grid-column: 1; grid-row: 1; align-self: center; color: #4a6b5c; font-size: 23px; }
.subject-page .variant-card .exam-copy { grid-column: 2; grid-row: 1; }
.subject-page .variant-card .exam-copy strong { color: #142333; font-size: 21px; line-height: 1.25; margin: 0 0 5px; }
.subject-page .variant-card .exam-copy small { color: #536b61; font-size: 13px; line-height: 1.4; }
.subject-page .variant-art { grid-column: 3; grid-row: 1; display: block; width: 64px; height: 64px; object-fit: contain; }
.subject-page .variant-status { display: inline-block; margin-bottom: 6px; padding: 3px 10px; border-radius: 999px; background: #d4f6b5; color: #3f8f13; font-size: 12px; font-style: normal; font-weight: 800; }
.subject-page .variant-meta { grid-column: 1 / -1; grid-row: 2; display: flex; justify-content: space-between; padding-top: 12px; border-top: 1px solid #cde9c2; color: #3e5a51; font-size: 13px; font-weight: 700; }
.subject-page .variant-card:active { transform: translateY(4px); box-shadow: 0 1px 0 #b9e5a5; }
.subject-page .section-heading { margin-bottom: 18px; }
.subject-page .section-heading p { color: #637387; font-size: 14px; }
.subject-page .quiz-list { display: grid; gap: 12px; overflow: visible; border: 0; border-radius: 0; background: none; box-shadow: none; }
.subject-page .quiz-row,
.subject-page .quiz-row + .quiz-row { display: grid; grid-template-columns: 20px 32px minmax(0, 1fr) 48px; gap: 8px; align-items: center; min-height: 91px; padding: 12px 14px; border: 1px solid #e8edf1; border-radius: 17px; background: #fff; box-shadow: 0 4px 0 #e1e6ea, 0 8px 20px rgba(36, 52, 74, .055); transition: transform 140ms cubic-bezier(0.23, 1, 0.32, 1), box-shadow 140ms cubic-bezier(0.23, 1, 0.32, 1), border-color 140ms ease; }
.subject-page .quiz-row .arrow { grid-column: 1; grid-row: 1; color: #6b7d8c; font-size: 20px; }
.subject-page .lesson-number { grid-column: 2; grid-row: 1; display: grid; place-items: center; width: 32px; height: 32px; border-radius: 50%; background: #e5f9d8; color: #3f9f11; font-size: 17px; font-weight: 900; }
.subject-page .quiz-copy { grid-column: 3; grid-row: 1; }
.subject-page .quiz-copy strong { margin: 0 0 3px; font-size: 17px; color: #263541; }
.subject-page .quiz-copy small { font-size: 12px; color: #69798a; }
.subject-page .quiz-icon { grid-column: 4; grid-row: 1; width: 48px; height: 48px; border-radius: 13px; background: #f0dcff; color: #9b58d8; box-shadow: 0 2px 0 #dec1f2; font-size: 24px; }
.subject-page .quiz-row:nth-child(2) .quiz-icon { background: #d8f1ff; color: #2c9ddf; box-shadow: 0 2px 0 #bcdff1; }
.subject-page .quiz-row:nth-child(3) .quiz-icon { background: #e9f9df; color: #53aa27; box-shadow: 0 2px 0 #c9ebbb; }
.subject-page .quiz-row:active { transform: translateY(3px); box-shadow: 0 1px 0 #e1e6ea; }
.subject-page .empty-state { margin: 0; padding: 26px; border: 2px dashed #dce8ef; border-radius: 20px; background: #f9fcfe; color: #627385; text-align: center; line-height: 1.65; }
.subject-page footer { margin-top: 44px; }
@keyframes subject-pop { from { opacity: 0; transform: translateY(8px) scale(.96); } to { opacity: 1; transform: translateY(0) scale(1); } }
@media (hover: hover) and (pointer: fine) {
  .subject-page .variant-card:hover { border-color: transparent; transform: translateY(-2px); }
  .subject-page .quiz-row:hover { background: #fff; transform: translateY(-2px); border-color: #bfe5b3; }
}
@media (max-width: 500px) {
  .subject-page .page { width: min(100% - 28px, 620px); padding-top: 18px; }
  .subject-page .back-link { margin-bottom: 24px; }
  .subject-page .subject-intro { grid-template-columns: minmax(0, 1fr) 82px; gap: 0 8px; margin-bottom: 36px; }
  .subject-page .subject-intro h1 { font-size: clamp(42px, 12vw, 52px); }
  .subject-page .subject-intro p { font-size: 15px; }
  .subject-page .subject-header-art { width: 82px; height: 82px; }
  .subject-page .variant-card { grid-template-columns: 18px minmax(0, 1fr) 54px; gap: 8px; min-height: 154px; padding: 15px; }
  .subject-page .variant-card .exam-copy strong { font-size: 18px; }
  .subject-page .variant-art { width: 54px; height: 54px; }
  .subject-page .quiz-row,
  .subject-page .quiz-row + .quiz-row { grid-template-columns: 18px 29px minmax(0, 1fr) 42px; gap: 6px; padding: 11px; }
  .subject-page .lesson-number { width: 29px; height: 29px; font-size: 15px; }
  .subject-page .quiz-icon { width: 42px; height: 42px; }
}
@media (prefers-reduced-motion: reduce) {
  .subject-page .subject-header-art { animation: subject-fade 200ms ease both; }
  .subject-page .variant-card,
  .subject-page .quiz-row,
  .subject-page .quiz-row + .quiz-row { transition: border-color 140ms ease, background-color 140ms ease; }
  .subject-page .variant-card:active,
  .subject-page .quiz-row:active { transform: none; }
}
@keyframes subject-fade { from { opacity: 0; } to { opacity: 1; } }

/* Make the question sets and their action visible at a glance. */
.subject-page .practice-shortcut { grid-column: 1; justify-self: start; display: inline-flex; align-items: center; gap: 8px; margin-top: 14px; padding: 9px 14px; border: 1px solid #b7e4a6; border-radius: 12px; background: #effbe9; color: #327e17; font-size: 14px; font-weight: 800; text-decoration: none; }
.subject-page .practice-shortcut:focus-visible, .subject-page .quiz-row:focus-visible { outline: 3px solid #247eb5; outline-offset: 3px; }
.subject-page #practice-section { scroll-margin-top: 20px; }
.subject-page #practice-section .quiz-row { border-color: #d6e9d0; }
.subject-page .practice-action { display: inline-flex; gap: 6px; align-items: center; margin-top: 8px; color: #348c16; font-size: 13px; font-weight: 800; }

.subject-page #physics-materials .quiz-row { background: #f7fafc; border-color: #e2eaf0; box-shadow: none; }
.subject-page #practice-section .quiz-row .arrow { visibility: hidden; }

.subject-page .best-badge { display: inline-flex; gap: 4px; align-items: center; margin-top: 8px; margin-inline-start: 10px; padding: 2px 9px; border-radius: 999px; background: #e9f9df; color: #2f7d12; font-size: 12px; font-weight: 800; line-height: 1.5; white-space: nowrap; direction: ltr; unicode-bidi: isolate; }

/* Keep each exam and its topic practice in one expandable group. */
.subject-page .variant-group { min-width: 0; border: 2px solid #d6e9d0; border-radius: 24px; background: #fff; box-shadow: 0 4px 0 #d9e5d4; }
.subject-page .variant-group .variant-card { margin: 0; cursor: pointer; list-style: none; box-shadow: none; animation: none; }
.subject-page .variant-group .variant-card::-webkit-details-marker { display: none; }
.subject-page .variant-group[open] .variant-card { border-radius: 22px 22px 0 0; }
.subject-page .variant-group .variant-card:hover, .subject-page .variant-group .variant-card:active { transform: none; box-shadow: none; }
.subject-page .variant-group .exam-arrow { transition: transform 140ms ease; }
.subject-page .variant-group[open] .exam-arrow { transform: rotate(180deg); }
.subject-page .variant-card:focus-visible { outline: 3px solid #247eb5; outline-offset: 4px; }
.subject-page .variant-content { padding: 20px; }
.subject-page .variant-start { display: flex; align-items: center; justify-content: center; min-height: 48px; padding: 12px 16px; border: 2px solid #b7e4a6; border-radius: 14px; background: var(--green-soft); color: #327e17; font-weight: 800; }
.subject-page .variant-content .subject-section { margin-top: 26px; scroll-margin-top: 20px; }
.subject-page .variant-content h3 { margin: 0 0 10px; color: #2c3a48; font-size: 18px; }
.subject-page .variant-content .quiz-row { border-color: #d6e9d0; grid-template-columns: 32px minmax(0, 1fr) 48px; }
.subject-page .variant-content .quiz-row .arrow { display: none; }
.subject-page .variant-content .lesson-number { grid-column: 1; }
.subject-page .variant-content .quiz-copy { grid-column: 2; }
.subject-page .variant-content .quiz-icon { grid-column: 3; }
@media (max-width: 500px) {
  .subject-page .variant-content { padding: 14px; }
  .subject-page .variant-content .quiz-row { grid-template-columns: 29px minmax(0, 1fr) 42px; }
}
@media (prefers-reduced-motion: reduce) {
  .subject-page .variant-group .exam-arrow { transition: none; }
}

/* Each exam version's own study material, next to its start button. */
.subject-page .variant-references { margin-top: 22px; }
.subject-page .variant-references p { margin: 0 0 10px; color: #637387; font-size: 14px; line-height: 1.5; }
.subject-page .reference-link { display: grid; grid-template-columns: 44px minmax(0, 1fr); gap: 12px; align-items: center; min-height: 64px; margin-top: 10px; padding: 11px 13px; border: 1px solid #dbe6ee; border-radius: 15px; background: #f7fafc; color: #263541; text-decoration: none; }
.subject-page .reference-icon { display: grid; place-items: center; width: 44px; height: 44px; border-radius: 12px; background: #d8f1ff; color: #1f7fb8; font-size: 14px; font-weight: 900; }
.subject-page .reference-copy strong { display: block; font-size: 15px; line-height: 1.4; }
.subject-page .reference-copy small { display: block; margin-top: 2px; color: #69798a; font-size: 12px; line-height: 1.4; }
.subject-page .reference-link:focus-visible { outline: 3px solid #247eb5; outline-offset: 3px; }
@media (hover: hover) and (pointer: fine) { .subject-page .reference-link:hover { border-color: #9fd0ec; background: #fff; } }