/* Playful Classroom (v08) — интерактивная Smart Board (цифровая панель) */

/* ─── Палитра smart-доски ─────────────────────────────────── */
:root {
  --sb-bezel-1: #2f333b;
  --sb-bezel-2: #1b1d22;
  --sb-canvas: #fbfcfe;
  --sb-grid: rgba(40, 70, 130, 0.06);
  --sb-toolbar: #eef2f7;
  --sb-line: #dfe6ef;
  --sb-ink: #2c3e50;
  --sb-ink-soft: #5a6678;
  --sb-blue: #1f5bb5;
  --sb-blue-dark: #184a96;
  --sb-red: #e23b3b;
  --sb-green: #2e9e5b;
  --sb-amber: #e0992b;
  --sb-muted: #8a96a8;
}

/* ─── Тёмная тема smart-доски ─────────────────────────────── */
.theme-dark {
  --sb-bezel-1: #1a1c22;
  --sb-bezel-2: #0e0f14;
  --sb-canvas: #1e2030;
  --sb-grid: rgba(100, 140, 200, 0.08);
  --sb-toolbar: #262838;
  --sb-line: #363850;
  --sb-ink: #c8d0e0;
  --sb-ink-soft: #8890a8;
  --sb-blue: #5a9cff;
  --sb-blue-dark: #3a7ae0;
  --sb-red: #ff5a5a;
  --sb-green: #4cce7a;
  --sb-amber: #e8b84a;
  --sb-muted: #6a7288;
}

/* ─── Лейаут ─────────────────────────────────────────────── */
.session-layout {
  display: grid;
  grid-template-columns: 280px 1fr;
  gap: 1.5rem;
  align-items: start;
}

/* ─── Боковая панель управления ───────────────────────────── */
.bulletin-board {
  background: #fff;
  border: 1px solid var(--sb-line);
  border-radius: 16px;
  box-shadow: 0 10px 28px rgba(40, 60, 90, 0.10);
  padding: 1rem 1rem 0.5rem;
  position: relative;
}
/* Зелёный LED «онлайн» */
.bulletin-pin {
  width: 9px; height: 9px;
  background: #2ecc71;
  border-radius: 50%;
  box-shadow: 0 0 0 3px rgba(46, 204, 113, 0.18), 0 0 8px rgba(46, 204, 113, 0.7);
  position: absolute;
  top: 14px; right: 14px;
  animation: sb-pulse 2s ease-in-out infinite;
}
@keyframes sb-pulse {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.45; }
}

.bulletin-section {
  background: #f7f9fc;
  border: 1px solid #eef2f7;
  border-left: 3px solid var(--sb-blue);
  border-radius: 10px;
  padding: 0.7rem 0.8rem;
  margin-bottom: 0.75rem;
}
.bulletin-section h6 {
  font-family: var(--font-ui);
  font-weight: 600;
  font-size: 0.92rem;
  color: var(--sb-ink);
  margin-bottom: 0.5rem;
  display: flex;
  align-items: center;
}
.bulletin-section h6 i { color: var(--sb-blue); }
.bulletin-section .small { color: var(--sb-ink-soft); }
.bulletin-section strong { color: var(--sb-ink); }

/* Прогресс-бар (цифровой) */
.chalk-progress-label {
  display: flex;
  justify-content: space-between;
  font-family: var(--font-ui);
  font-size: 0.85rem;
  font-weight: 500;
  color: var(--sb-ink-soft);
  margin-bottom: 0.4rem;
}
.chalk-progress-track {
  height: 8px;
  background: #e7edf4;
  border-radius: 999px;
  overflow: hidden;
}
.chalk-progress-fill {
  height: 100%;
  width: 0;
  background: linear-gradient(90deg, var(--sb-blue) 0%, #3d8de0 100%);
  border-radius: 999px;
  transition: width 0.5s ease;
}

/* ─── Корпус панели (тёмная глянцевая рамка) ──────────────── */
.board-frame {
  background: linear-gradient(155deg, var(--sb-bezel-1) 0%, var(--sb-bezel-2) 100%);
  border-radius: 18px;
  padding: 13px;
  box-shadow:
    0 20px 48px rgba(0, 0, 0, 0.32),
    inset 0 1px 0 rgba(255, 255, 255, 0.07),
    inset 0 0 0 1px rgba(0, 0, 0, 0.55);
  display: flex;
  flex-direction: column;
  min-height: 72vh;
  position: relative;
}
/* Логотип-брендинг на нижней рамке */
.board-frame::after {
  content: "Зубри.РФ";
  position: absolute;
  bottom: 1px; left: 50%;
  transform: translateX(-50%);
  font-family: var(--font-chalk);
  font-size: 0.7rem;
  letter-spacing: 0.05em;
  color: rgba(255, 255, 255, 0.22);
}

/* ─── Цифровой холст ──────────────────────────────────────── */
.board-surface {
  background-color: var(--sb-canvas);
  background-image: radial-gradient(circle, var(--sb-grid) 1px, transparent 1px);
  background-size: 22px 22px;
  border-radius: 7px;
  flex: 1;
  display: flex;
  flex-direction: column;
  overflow: hidden;
  min-height: 0;
  box-shadow: inset 0 0 0 1px rgba(0, 0, 0, 0.06);
}

/* ─── Тулбар (инструменты доски) ──────────────────────────── */
.board-toolbar {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  padding: 0.45rem 0.7rem;
  background: var(--sb-toolbar);
  border-bottom: 1px solid var(--sb-line);
  flex-shrink: 0;
  flex-wrap: wrap;
}
.board-toolbar__title {
  display: flex;
  align-items: center;
  gap: 0.45rem;
  font-family: var(--font-ui);
  font-weight: 600;
  font-size: 0.95rem;
  color: var(--sb-ink);
  margin-right: auto;
  min-width: 0;
}
.board-toolbar__title > i { color: var(--sb-blue); }
.board-toolbar__title span { overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.board-toolbar__sub { color: var(--sb-muted); font-weight: 500; font-size: 0.85rem; }

.board-toolbar__tools {
  display: flex;
  align-items: center;
  gap: 0.25rem;
}
.board-tool {
  width: 32px; height: 32px;
  border-radius: 8px;
  display: grid;
  place-items: center;
  background: transparent;
  border: 1px solid transparent;
  color: var(--sb-ink-soft);
  cursor: pointer;
  font-size: 0.85rem;
  transition: background 0.15s, border-color 0.15s, color 0.15s;
}
.board-tool:hover {
  background: #fff;
  border-color: #d4dce6;
  color: var(--sb-ink);
}
.board-tool.is-active {
  background: #fff;
  border-color: var(--sb-blue);
  color: var(--sb-blue);
  box-shadow: 0 1px 4px rgba(31, 91, 181, 0.18);
}
.board-tool__sep {
  width: 1px; height: 20px;
  background: var(--sb-line);
  margin: 0 0.2rem;
}
.board-tool--labeled {
  width: auto;
  padding: 0 0.65rem;
  gap: 0.35rem;
  display: flex;
  align-items: center;
}
.board-tool__label {
  font-family: var(--font-ui);
  font-size: 0.82rem;
  font-weight: 500;
  white-space: nowrap;
}
.tool-color {
  width: 18px; height: 18px;
  border-radius: 50%;
  cursor: pointer;
  border: 2px solid #fff;
  box-shadow: 0 0 0 1px rgba(0, 0, 0, 0.12);
  transition: transform 0.12s;
}
.tool-color:hover { transform: scale(1.15); }
.tool-color.is-active {
  box-shadow: 0 0 0 2px var(--sb-blue);
  transform: scale(1.1);
}

/* Статус-чип */
.board-status {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  font-family: var(--font-ui);
  font-size: 0.8rem;
  font-weight: 500;
  color: var(--sb-ink-soft);
  background: #fff;
  border: 1px solid var(--sb-line);
  border-radius: 999px;
  padding: 0.2rem 0.65rem;
}
.board-status__led {
  width: 7px; height: 7px;
  border-radius: 50%;
  background: #2ecc71;
  box-shadow: 0 0 6px rgba(46, 204, 113, 0.7);
}

/* ─── Обёртка canvas + сообщения ─────────────────────────── */
.board-canvas-wrap {
  position: relative;
  flex: 1;
  min-height: 0;
  overflow: hidden;
  display: flex;
  flex-direction: column;
}

/* ─── Canvas рисования ────────────────────────────────────── */
#drawing-canvas {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  pointer-events: none;
  z-index: 10;
  touch-action: none;
}
.draw-mode #drawing-canvas {
  pointer-events: all;
  cursor: crosshair;
}
/* В режиме рисования блокируем прокрутку и выделение под canvas */
.draw-mode .messages-container {
  overflow: hidden;
  user-select: none;
  pointer-events: none;
}

/* Подсказка «режим рисования» */
.draw-mode-hint {
  position: absolute;
  top: 8px;
  left: 50%;
  transform: translateX(-50%);
  background: rgba(31, 91, 181, 0.9);
  color: #fff;
  font-family: var(--font-ui);
  font-size: 0.8rem;
  font-weight: 500;
  padding: 0.3rem 0.85rem;
  border-radius: 999px;
  white-space: nowrap;
  pointer-events: none;
  z-index: 20;
  opacity: 0;
  transition: opacity 0.2s;
}
.draw-mode-hint.visible { opacity: 1; }

/* ─── Область сообщений ───────────────────────────────────── */
.messages-container {
  flex: 1;
  overflow-y: auto;
  padding: 1.1rem 1.3rem;
  min-height: 0;
}
.messages-container::-webkit-scrollbar { width: 8px; }
.messages-container::-webkit-scrollbar-track { background: transparent; }
.messages-container::-webkit-scrollbar-thumb {
  background: #ccd6e2;
  border-radius: 4px;
  border: 2px solid var(--sb-canvas);
}

/* Пустое состояние */
.board-empty {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  height: 100%;
  min-height: 200px;
  color: var(--sb-muted);
  font-family: var(--font-ui);
  font-size: 1.05rem;
  gap: 0.6rem;
}
.board-empty i { font-size: 2.6rem; color: #c3cedb; }

/* ─── Сообщение репетитора (написано маркером) ────────────── */
.chalk-msg {
  margin-bottom: 1.35rem;
  display: flex;
  align-items: flex-start;
  gap: 0.7rem;
}
.chalk-msg-avatar {
  width: 34px; height: 34px;
  background: linear-gradient(135deg, var(--sb-blue), #3d8de0);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  margin-top: 2px;
  box-shadow: 0 2px 6px rgba(31, 91, 181, 0.3);
}
.chalk-msg-avatar i { color: #fff; font-size: 0.9rem; }
.chalk-msg-body { flex: 1; min-width: 0; }

/* Бейдж урока — рукописный маркером */
.chalk-badge {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  background: rgba(31, 91, 181, 0.08);
  border: 1px solid rgba(31, 91, 181, 0.25);
  border-radius: 8px;
  padding: 0.2rem 0.7rem;
  font-family: var(--font-chalk);
  font-size: 1.1rem;
  color: var(--sb-blue);
  margin-bottom: 0.5rem;
}
.chalk-badge i { font-size: 0.85rem; }

.chalk-msg-content {
  font-family: var(--font-ui);
  font-size: 0.97rem;
  color: var(--sb-ink);
  line-height: 1.7;
}
/* Заголовки — рукописный маркер (синий) */
.chalk-msg-content h1,
.chalk-msg-content h2,
.chalk-msg-content h3 {
  font-family: var(--font-chalk);
  color: var(--sb-blue);
  margin-top: 0.85rem;
  margin-bottom: 0.35rem;
  line-height: 1.2;
}
.chalk-msg-content h1 { font-size: 1.9rem; }
.chalk-msg-content h2 { font-size: 1.6rem; }
.chalk-msg-content h3 { font-size: 1.35rem; }
.chalk-msg-content code {
  background: #eef2f7;
  color: #c0392b;
  padding: 0.12em 0.42em;
  border-radius: 5px;
  font-size: 0.88em;
}
.chalk-msg-content pre {
  background: #2b2e35;
  border-radius: 8px;
  padding: 0.85rem 1rem;
  overflow-x: auto;
  margin: 0.6rem 0;
}
.chalk-msg-content pre code {
  background: none;
  color: #e6edf3;
  padding: 0;
}
.chalk-msg-content strong { color: #1a2533; font-weight: 600; }
.chalk-msg-content a { color: var(--sb-blue); text-decoration: underline; }
.chalk-msg-content ul, .chalk-msg-content ol { padding-left: 1.4em; }
.chalk-msg-content blockquote {
  border-left: 3px solid var(--sb-blue);
  padding-left: 0.85rem;
  color: var(--sb-ink-soft);
  margin: 0.5rem 0;
  background: rgba(31, 91, 181, 0.04);
  border-radius: 0 6px 6px 0;
}
.chalk-msg-time {
  font-family: var(--font-ui);
  font-size: 0.75rem;
  color: var(--sb-muted);
  margin-top: 0.35rem;
}

/* ─── Сообщение ученика (цифровой стикер) ─────────────────── */
.sticky-msg {
  margin-bottom: 1.35rem;
  display: flex;
  justify-content: flex-end;
}
.sticky-msg-inner {
  background: #fff7cc;
  color: #4a3f1a;
  border-radius: 12px 12px 4px 12px;
  padding: 0.65rem 0.95rem;
  max-width: 72%;
  box-shadow: 0 4px 14px rgba(180, 150, 40, 0.28), inset 0 1px 0 rgba(255, 255, 255, 0.5);
  transform: rotate(-0.6deg);
  position: relative;
}
.sticky-msg-text {
  font-family: var(--font-ui);
  font-size: 0.95rem;
  line-height: 1.55;
  word-break: break-word;
  white-space: pre-wrap;
}
.sticky-msg-text code {
  background: rgba(0,0,0,0.07);
  padding: 0.1em 0.35em;
  border-radius: 4px;
  font-size: 0.88em;
}
.sticky-msg-time {
  font-family: var(--font-ui);
  font-size: 0.72rem;
  color: #a8924e;
  margin-top: 0.25rem;
  text-align: right;
}

/* ─── Разделитель (маркерная линия) ──────────────────────── */
.chalk-divider {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  margin: 1.4rem 0;
}
.chalk-divider::before,
.chalk-divider::after {
  content: "";
  flex: 1;
  border-top: 2px solid #d8e0ea;
}
.chalk-divider-label {
  font-family: var(--font-chalk);
  font-size: 1rem;
  color: var(--sb-blue);
  white-space: nowrap;
  flex-shrink: 0;
  background: rgba(31, 91, 181, 0.07);
  padding: 0.1rem 0.7rem;
  border-radius: 999px;
}

/* ─── Кнопки действий ─────────────────────────────────────── */
.board-action-btns {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin-top: 0.8rem;
}
.btn-chalk {
  background: #fff;
  border: 1.5px solid #cfd8e3;
  color: var(--sb-ink);
  font-family: var(--font-ui);
  font-weight: 500;
  font-size: 0.9rem;
  padding: 0.4rem 0.95rem;
  border-radius: 999px;
  cursor: pointer;
  transition: background 0.15s, color 0.15s, border-color 0.15s, transform 0.1s;
}
.btn-chalk:hover {
  border-color: var(--sb-blue);
  color: var(--sb-blue);
  background: #f0f5fc;
  transform: translateY(-1px);
}
.btn-chalk:disabled { opacity: 0.5; cursor: not-allowed; transform: none; }

.btn-chalk-green {
  border-color: rgba(46, 158, 91, 0.5);
  color: var(--sb-green);
}
.btn-chalk-green:hover {
  border-color: var(--sb-green);
  color: var(--sb-green);
  background: rgba(46, 158, 91, 0.08);
}
.btn-chalk-plan {
  border-color: rgba(224, 153, 43, 0.5);
  color: var(--sb-amber);
}
.btn-chalk-plan:hover {
  border-color: var(--sb-amber);
  color: var(--sb-amber);
  background: rgba(224, 153, 43, 0.08);
}
.btn-chalk-next {
  background: var(--sb-blue);
  border-color: var(--sb-blue);
  color: #fff;
}
.btn-chalk-next:hover {
  background: var(--sb-blue-dark);
  border-color: var(--sb-blue-dark);
  color: #fff;
}

/* ─── Нижняя панель ввода ─────────────────────────────────── */
.chalk-tray {
  background: var(--sb-toolbar);
  border-top: 1px solid var(--sb-line);
  padding: 0.7rem 0.9rem 0.5rem;
  flex-shrink: 0;
}
.chalk-tray-disclaimer {
  font-family: var(--font-ui);
  font-size: 0.78rem;
  color: var(--sb-muted);
  margin-bottom: 0.45rem;
  display: flex;
  align-items: center;
  gap: 0.35rem;
}
.chalk-tray-disclaimer i { color: var(--sb-amber); }

.chalk-input-row {
  display: flex;
  gap: 0.6rem;
  align-items: center;
}
.chalk-input-row--practice {
  align-items: flex-end;
}
.chalk-input {
  width: 100%;
  background: #fff;
  border: 1.5px solid #d4dce6;
  border-radius: 12px;
  padding: 0.6rem 0.85rem;
  font-family: var(--font-ui);
  font-size: 0.95rem;
  color: var(--sb-ink);
  resize: none;
  line-height: 1.5;
  transition: border-color 0.15s, box-shadow 0.15s;
}
.chalk-input--practice {
  min-height: 9.5rem;
  max-height: 22rem;
  resize: vertical;
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, "Liberation Mono", monospace;
  font-size: 0.9rem;
  line-height: 1.45;
  white-space: pre-wrap;
  overflow-y: auto;
  tab-size: 4;
}
.chalk-input:focus {
  outline: none;
  border-color: var(--sb-blue);
  box-shadow: 0 0 0 3px rgba(31, 91, 181, 0.12);
}
.chalk-input::placeholder { color: #9aa6b6; }

.chalk-hint {
  font-family: var(--font-ui);
  font-size: 0.75rem;
  color: var(--sb-muted);
  margin-top: 0.3rem;
}
.chalk-hint kbd {
  background: #fff;
  border: 1px solid var(--sb-line);
  border-radius: 4px;
  padding: 0.05rem 0.3rem;
  font-size: 0.72rem;
  color: var(--sb-ink-soft);
}

.btn-chalk-send {
  background: var(--sb-blue);
  border: none;
  border-radius: 12px;
  width: 44px; height: 44px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: #fff;
  font-size: 1rem;
  cursor: pointer;
  flex-shrink: 0;
  transition: background 0.15s, transform 0.1s;
}
.btn-chalk-send:hover { background: var(--sb-blue-dark); transform: scale(1.05); }
.btn-chalk-send:disabled { opacity: 0.5; cursor: not-allowed; transform: none; }

/* ─── Адаптив ─────────────────────────────────────────────── */
@media (max-width: 992px) {
  .session-layout { grid-template-columns: 1fr; }
  .board-frame { min-height: 65vh; }
  .sticky-msg-inner { max-width: 88%; }
}

@media (max-width: 576px) {
  .board-frame { padding: 9px; }
  .board-toolbar { gap: 0.4rem; padding: 0.4rem 0.5rem; }
  .board-toolbar__title { font-size: 0.88rem; }
  .board-toolbar__tools .tool-color { display: none; }
  .board-tool__sep { display: none; }
  .chalk-msg-content { font-size: 0.92rem; }
  .chalk-tray { padding: 0.5rem 0.6rem; }
  .sticky-msg-inner { max-width: 94%; }
}

/* ─── Кнопка практического задания ──────────────────────────── */
.btn-chalk-practical {
  border-color: rgba(46, 158, 91, 0.5);
  color: var(--sb-green);
}
.btn-chalk-practical:hover {
  border-color: var(--sb-green);
  color: var(--sb-green);
  background: rgba(46, 158, 91, 0.08);
}
.btn-chalk-xs {
  font-size: 0.8rem;
  padding: 0.25rem 0.6rem;
}

/* ─── Форма практического задания ────────────────────────────── */
.practical-form {
  background: #f7f9fc;
  border: 1px solid var(--sb-line);
  border-left: 3px solid var(--sb-green);
  border-radius: 10px;
  padding: 0.9rem;
}
.practical-form__title {
  font-family: var(--font-chalk);
  font-size: 1.18rem;
  color: var(--sb-green);
  margin-bottom: 0.7rem;
}
.practical-question {
  background: #fff;
  border: 1px solid #eef2f7;
  border-radius: 8px;
  padding: 0.7rem;
  margin-bottom: 0.6rem;
}
.practical-question__header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 0.4rem;
}
.practical-question__number {
  font-family: var(--font-chalk);
  font-size: 1.05rem;
  color: var(--sb-ink);
  font-weight: 600;
}
.practical-question__score {
  font-family: var(--font-ui);
  font-size: 0.78rem;
  color: var(--sb-muted);
}
.practical-question__text {
  font-family: var(--font-ui);
  font-size: 0.95rem;
  color: var(--sb-ink);
  line-height: 1.6;
  margin-bottom: 0.5rem;
}
.practical-question__context {
  background: rgba(31, 91, 181, 0.05);
  border-left: 3px solid var(--sb-blue);
  padding: 0.5rem 0.7rem;
  border-radius: 0 6px 6px 0;
  margin-bottom: 0.5rem;
  font-size: 0.88rem;
  color: var(--sb-ink-soft);
}
.practical-question__input {
  width: 100%;
  background: #fbfcfe;
  border: 1.5px solid #d4dce6;
  border-radius: 8px;
  padding: 0.55rem 0.7rem;
  font-family: var(--font-ui);
  font-size: 0.92rem;
  color: var(--sb-ink);
  resize: vertical;
  transition: border-color 0.15s;
}
.practical-question__input:focus {
  outline: none;
  border-color: var(--sb-green);
  box-shadow: 0 0 0 3px rgba(46, 158, 91, 0.1);
}
.practical-question__criteria {
  font-family: var(--font-ui);
  font-size: 0.78rem;
  color: var(--sb-muted);
  margin-top: 0.3rem;
  display: flex;
  align-items: center;
  gap: 0.3rem;
}
.btn-chalk-practical-submit {
  background: var(--sb-green);
  border-color: var(--sb-green);
  color: #fff;
  padding: 0.5rem 1.2rem;
  border-radius: 10px;
  font-family: var(--font-ui);
  font-weight: 600;
  font-size: 0.9rem;
  border: none;
  cursor: pointer;
  transition: background 0.15s;
}
.btn-chalk-practical-submit:hover {
  background: #258f4f;
  color: #fff;
}
.btn-chalk-practical-submit:disabled {
  opacity: 0.5;
  cursor: not-allowed;
}

/* ─── Результат практического задания ────────────────────────── */
.practical-result {
  background: #f7f9fc;
  border: 1px solid var(--sb-line);
  border-radius: 10px;
  padding: 0.9rem;
}
.practical-result__header {
  font-family: var(--font-chalk);
  font-size: 1.2rem;
  text-align: center;
  padding: 0.6rem;
  border-radius: 8px;
  margin-bottom: 0.7rem;
}
.practical-result__header--passed {
  background: rgba(46, 158, 91, 0.1);
  color: var(--sb-green);
}
.practical-result__header--failed {
  background: rgba(226, 59, 59, 0.1);
  color: var(--sb-red);
}
.practical-result__score {
  text-align: center;
  font-family: var(--font-chalk);
  margin-bottom: 0.7rem;
}
.practical-result__score-value {
  font-size: 2.2rem;
  color: var(--sb-ink);
  font-weight: 700;
}
.practical-result__score-sep {
  font-size: 1.4rem;
  color: var(--sb-muted);
}
.practical-result__score-max {
  font-size: 1.4rem;
  color: var(--sb-ink-soft);
}
.practical-result__score-pass {
  font-family: var(--font-ui);
  font-size: 0.8rem;
  color: var(--sb-muted);
  display: block;
  margin-top: 0.15rem;
}
.practical-result__feedback {
  background: #fff;
  border: 1px solid #eef2f7;
  border-radius: 8px;
  padding: 0.6rem;
  margin-bottom: 0.6rem;
  font-family: var(--font-ui);
  font-size: 0.92rem;
  line-height: 1.6;
}
.practical-result__item {
  background: #fff;
  border: 1px solid #eef2f7;
  border-radius: 8px;
  padding: 0.6rem;
  margin-bottom: 0.5rem;
}
.practical-result__item--correct {
  border-left: 3px solid var(--sb-green);
}
.practical-result__item--wrong {
  border-left: 3px solid var(--sb-red);
}
.practical-result__item-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 0.3rem;
}
.practical-result__item-num {
  font-family: var(--font-chalk);
  font-size: 0.95rem;
  color: var(--sb-ink);
  font-weight: 600;
}
.practical-result__item-score {
  font-family: var(--font-ui);
  font-size: 0.85rem;
  font-weight: 600;
}
.practical-result__item--correct .practical-result__item-score { color: var(--sb-green); }
.practical-result__item--wrong .practical-result__item-score { color: var(--sb-red); }
.practical-result__item-feedback {
  font-family: var(--font-ui);
  font-size: 0.88rem;
  color: var(--sb-ink-soft);
  line-height: 1.5;
}
.practical-result__item-explanation {
  font-family: var(--font-ui);
  font-size: 0.85rem;
  color: var(--sb-blue);
  margin-top: 0.3rem;
  padding: 0.3rem 0.5rem;
  background: rgba(31, 91, 181, 0.05);
  border-radius: 6px;
}

/* ─── Бейдж практического задания ────────────────────────────── */
.chalk-badge--practical {
  background: rgba(46, 158, 91, 0.08);
  border-color: rgba(46, 158, 91, 0.25);
  color: var(--sb-green);
}
.chalk-badge-passed {
  font-family: var(--font-ui);
  font-size: 0.75rem;
  font-weight: 600;
  color: #fff;
  background: var(--sb-green);
  padding: 0.1rem 0.4rem;
  border-radius: 999px;
}

/* ─── Тёмная тема: переопределения ────────────────────────────── */
.theme-dark .board-tool:hover {
  background: var(--surface);
  border-color: var(--sb-line);
}
.theme-dark .board-tool.is-active {
  background: var(--surface);
}
.theme-dark .tool-color {
  border-color: var(--surface);
}
.theme-dark .board-status {
  background: var(--surface);
}
.theme-dark .bulletin-board {
  background: var(--surface);
  border-color: var(--sb-line);
}
.theme-dark .board-frame {
  background: var(--chalkboard);
}
.theme-dark .board-toolbar {
  background: var(--sb-toolbar);
}
.theme-dark .chalk-msg {
  background: var(--surface);
  border-color: var(--sb-line);
}
.theme-dark .chalk-msg-content strong {
  color: var(--sb-ink);
}
.theme-dark .chalk-msg-content code {
  background: rgba(0,0,0,0.3);
  color: var(--sb-red);
}
.theme-dark .sticky-msg-inner {
  background: #3a352a;
  color: #d8d0b0;
  box-shadow: 0 4px 14px rgba(0,0,0,0.4);
}
.theme-dark .sticky-msg-time {
  color: #8a7a4a;
}
.theme-dark .chalk-input {
  background: var(--surface);
  border-color: var(--sb-line);
  color: var(--sb-ink);
}
.theme-dark .chalk-input--practice {
  background: #1a1d28;
  border-color: #3a4055;
}
.theme-dark .chalk-input::placeholder {
  color: var(--sb-muted);
}
.theme-dark .chalk-hint kbd {
  background: var(--surface);
  border-color: var(--sb-line);
}
.theme-dark .practical-form {
  background: var(--surface);
  border-color: var(--sb-line);
}
.theme-dark .practical-question {
  background: #222438;
  border-color: var(--sb-line);
}
.theme-dark .practical-question__input {
  background: var(--surface);
  border-color: var(--sb-line);
  color: var(--sb-ink);
}
.theme-dark .practical-result {
  background: var(--surface);
  border-color: var(--sb-line);
}
.theme-dark .practical-result__feedback {
  background: #222438;
  border-color: var(--sb-line);
}
.theme-dark .practical-result__item {
  background: #222438;
  border-color: var(--sb-line);
}
.theme-dark .practical-result__item--correct {
  border-color: var(--sb-green);
}
.theme-dark .practical-result__item--wrong {
  border-color: var(--sb-red);
}
.theme-dark .board-empty i {
  color: var(--sb-muted);
}
.theme-dark .btn-chalk {
  background: #282b40;
  border: 2px solid #4a5070;
  color: #d0d8e8;
}
.theme-dark .btn-chalk:hover {
  background: #323660;
  border-color: var(--sb-blue);
  color: var(--sb-blue);
}
.theme-dark .btn-chalk:disabled {
  opacity: 0.55;
  background: #202238;
  border-color: #3a3d58;
  color: #6a7290;
}
.theme-dark .chalk-msg-avatar i {
  color: var(--sb-ink);
}
.theme-dark .bulletin-section {
  background: #222438;
  border-color: var(--sb-line);
}
.theme-dark .chalk-progress-track {
  background: #363850;
}

/* ── Результат урочного квиза ─────────────────────────────── */
.quiz-result-banner {
  margin-top: 0.75rem;
  padding: 0.7rem 0.9rem;
  border-radius: 10px;
  background: rgba(46, 158, 91, 0.10);
  border: 1px solid rgba(46, 158, 91, 0.35);
}
.quiz-result-banner.is-failed {
  background: rgba(226, 59, 59, 0.08);
  border-color: rgba(226, 59, 59, 0.30);
}
.quiz-result-score {
  font-weight: 600;
  color: #2e9e5b;
}
.quiz-result-banner.is-failed .quiz-result-score {
  color: #e23b3b;
}
.quiz-result-feedback {
  margin-top: 0.4rem;
  font-size: 0.95rem;
  line-height: 1.5;
}
.theme-dark .quiz-result-banner {
  background: rgba(46, 158, 91, 0.14);
  border-color: rgba(46, 158, 91, 0.40);
}
.theme-dark .quiz-result-banner.is-failed {
  background: rgba(226, 59, 59, 0.12);
  border-color: rgba(226, 59, 59, 0.40);
}

/* ─── План обучения (блоки/уроки) ─────────────────────────── */
.chalk-plan-block {
  background: rgba(224, 153, 43, 0.05);
  border: 1px solid rgba(224, 153, 43, 0.2);
  border-radius: 10px;
  padding: 0.7rem 0.85rem;
  margin-bottom: 0.6rem;
}
.chalk-plan-block-header {
  display: flex;
  align-items: center;
  gap: 0.55rem;
  margin-bottom: 0.3rem;
}
.chalk-plan-block-number {
  font-family: var(--font-chalk);
  font-size: 0.85rem;
  color: var(--sb-amber);
  background: rgba(224, 153, 43, 0.12);
  padding: 0.05rem 0.45rem;
  border-radius: 6px;
  flex-shrink: 0;
}
.chalk-plan-block-title {
  font-family: var(--font-ui);
  font-weight: 600;
  font-size: 0.95rem;
  color: var(--sb-ink);
}
.chalk-plan-block-desc {
  font-family: var(--font-ui);
  font-size: 0.85rem;
  color: var(--sb-ink-soft);
  margin: 0.2rem 0 0.4rem 0;
  line-height: 1.4;
}
.chalk-plan-lessons {
  margin-left: 1rem;
  border-left: 2px solid rgba(224, 153, 43, 0.15);
  padding-left: 0.6rem;
}
.chalk-plan-lesson {
  display: flex;
  align-items: center;
  gap: 0.45rem;
  padding: 0.2rem 0;
}
.chalk-plan-lesson-number {
  font-family: var(--font-ui);
  font-size: 0.78rem;
  color: var(--sb-ink-soft);
  background: var(--sb-toolbar);
  padding: 0.05rem 0.35rem;
  border-radius: 4px;
  flex-shrink: 0;
}
.chalk-plan-lesson-title {
  font-family: var(--font-ui);
  font-size: 0.9rem;
  color: var(--sb-ink);
}
.chalk-plan-estimated {
  font-family: var(--font-ui);
  font-size: 0.82rem;
  color: var(--sb-muted);
  display: flex;
  align-items: center;
  gap: 0.3rem;
}
.theme-dark .chalk-plan-block {
  background: rgba(224, 153, 43, 0.08);
  border-color: rgba(224, 153, 43, 0.25);
}

/* ─── Состояние загрузки (спиннер) ────────────────────────── */
.board-empty--loading i {
  animation: sb-spin 1s linear infinite;
}
@keyframes sb-spin {
  to { transform: rotate(360deg); }
}

/* ─── Свёрнутая история переписки ─────────────────────────── */
.history-collapse {
  margin: 0 0 1.1rem;
}
.history-collapse__summary {
  list-style: none;
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.4rem 0.9rem;
  border-radius: 999px;
  background: rgba(31, 91, 181, 0.07);
  border: 1px dashed var(--sb-line);
  color: var(--sb-blue);
  font-family: var(--font-chalk);
  font-size: 1rem;
  user-select: none;
  transition: background 0.15s, color 0.15s;
}
.history-collapse__summary::-webkit-details-marker { display: none; }
.history-collapse__summary::marker { content: ""; }
.history-collapse__summary:hover {
  background: rgba(31, 91, 181, 0.14);
}
.history-collapse__summary .fa-chevron-down {
  transition: transform 0.15s;
  font-size: 0.7rem;
}
.history-collapse[open] > .history-collapse__summary .fa-chevron-down {
  transform: rotate(180deg);
}
.history-collapse__body {
  padding-top: 0.9rem;
  margin-top: 0.75rem;
  border-top: 1px dashed var(--sb-line);
}
.theme-dark .history-collapse__summary {
  background: rgba(255, 255, 255, 0.06);
  color: var(--sb-muted);
}
.theme-dark .history-collapse__summary:hover {
  background: rgba(255, 255, 255, 0.10);
}

/* ─── Кнопки промотки вверх/вниз ──────────────────────────── */
.scroll-btn {
  width: 36px; height: 36px;
  border-radius: 50%;
  background: var(--sb-blue);
  border: none;
  color: #fff;
  cursor: pointer;
  display: grid;
  place-items: center;
  font-size: 1rem;
  box-shadow: 0 4px 14px rgba(31, 91, 181, 0.35);
  transition: transform 0.15s, box-shadow 0.15s;
  opacity: 0.95;
}
.scroll-btn:hover {
  transform: scale(1.08);
  box-shadow: 0 6px 20px rgba(31, 91, 181, 0.45);
  opacity: 1;
}
.scroll-btn:active {
  transform: scale(0.92);
}