:root {
  --bg: #181a20;
  --card: #23262f;
  --accent: #4f8cff;
  --accent2: #6fc3ff;
  --text: #f1f1f1;
  --muted: #a0a0a0;
  --border: #31343c;
  --success: #3ec97a;
  --danger: #e05252;
  --warning: #f5a623;
}

* { box-sizing: border-box; }

body {
  background: var(--bg);
  color: var(--text);
  font-family: 'Segoe UI', Arial, sans-serif;
  margin: 0;
  min-height: 100vh;
}

#lines-bg {
  position: fixed;
  top: 0; left: 0;
  width: 100vw; height: 100vh;
  z-index: 0;
  pointer-events: none;
  display: block;
}

.header, .container, .auth-wrap, .admin-wrap {
  position: relative;
  z-index: 1;
}

/* ── Header ── */
.header {
  background: var(--card);
  padding: 12px 24px;
  border-bottom: 1px solid var(--border);
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.header h1 { margin: 0; font-size: 1.3rem; letter-spacing: 1px; }
.header h1 a { text-decoration: none; color: inherit; }

.user-info {
  display: flex;
  align-items: center;
  gap: 10px;
  color: var(--muted);
  font-size: 1rem;
}

.user-info span { cursor: pointer; }
.user-info span:hover { color: var(--text); }
.header-emoji { margin-right: 6px; font-size: 1.15rem; }

.avatar {
  width: 32px; height: 32px;
  border-radius: 50%;
  object-fit: cover;
  border: 1.5px solid var(--border);
}

.admin-btn {
  background: var(--accent);
  color: white;
  border: none;
  border-radius: 6px;
  cursor: pointer;
  font-size: 0.85rem;
  font-weight: 500;
  padding: 6px 14px;
  transition: all 0.2s;
  text-decoration: none;
  display: inline-block;
}
.admin-btn:hover { background: #3d7ae6; transform: translateY(-1px); }

/* ── Container ── */
.container {
  max-width: 720px;
  margin: 32px auto;
  padding: 0 16px;
}

/* ── Cards ── */
.card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 24px 20px;
  margin-bottom: 16px;
  transition: box-shadow 0.2s, border-color 0.2s;
}

.card.clickable { cursor: pointer; }
.card.clickable:hover { box-shadow: 0 2px 16px 0 #0004; border-color: var(--accent); }
.card.solved { border-color: var(--success) !important; }
.card.wrong { border-color: var(--danger) !important; }

/* ── Progress bar ── */
.progress-bar {
  width: 100%;
  height: 8px;
  background: var(--border);
  border-radius: 6px;
  overflow: hidden;
  margin-top: 8px;
}
.progress-bar-inner {
  height: 100%;
  background: linear-gradient(90deg, var(--accent), var(--accent2));
  border-radius: 6px 0 0 6px;
  transition: width 0.4s;
}

/* ── Status badges ── */
.badge {
  display: inline-block;
  padding: 2px 10px;
  border-radius: 20px;
  font-size: 0.8rem;
  font-weight: 600;
}
.badge-accepted { background: #1e4a31; color: var(--success); }
.badge-wrong_answer { background: #4a1e1e; color: var(--danger); }
.badge-pending { background: #2c2c1e; color: var(--warning); }
.badge-runtime_error { background: #4a1e1e; color: #ff8c8c; }
.badge-timeout { background: #2c2c1e; color: var(--warning); }
.badge-style_error { background: #3a2a00; color: #ffcc44; }

/* ── Buttons ── */
.btn {
  display: inline-block;
  padding: 10px 24px;
  border-radius: 8px;
  border: none;
  cursor: pointer;
  font-size: 0.95rem;
  font-weight: 600;
  transition: all 0.2s;
  text-decoration: none;
}
.btn-primary { background: var(--accent); color: white; }
.btn-primary:hover { background: #3d7ae6; transform: translateY(-1px); }
.btn-secondary { background: transparent; color: var(--accent); border: 1.5px solid var(--accent); }
.btn-secondary:hover { background: rgba(79,140,255,0.1); }
.btn-danger { background: var(--danger); color: white; }
.btn-danger:hover { background: #c44; }
.btn-sm { padding: 5px 12px; font-size: 0.82rem; }

/* ── Forms ── */
.form-group { margin-bottom: 16px; }
.form-group label { display: block; margin-bottom: 6px; color: var(--muted); font-size: 0.9rem; }

input[type="text"], input[type="email"], input[type="password"],
input[type="number"], input[type="date"], select, textarea {
  width: 100%;
  background: #1a1d24;
  border: 1.5px solid var(--border);
  border-radius: 8px;
  color: var(--text);
  padding: 10px 14px;
  font-size: 0.95rem;
  outline: none;
  transition: border-color 0.2s;
  font-family: inherit;
}
input:focus, select:focus, textarea:focus { border-color: var(--accent); }

/* Дата: инвертируем иконку календаря под тёмную тему */
input[type="date"] { color-scheme: dark; }
input[type="date"]::-webkit-calendar-picker-indicator {
  filter: invert(0.7);
  cursor: pointer;
}

/* Загрузка файла: кастомная кнопка в стиле дизайна */
input[type="file"] {
  width: 100%;
  background: #1a1d24;
  border: 1.5px solid var(--border);
  border-radius: 8px;
  color: var(--muted);
  padding: 8px 10px;
  font-size: 0.9rem;
  font-family: inherit;
  cursor: pointer;
}
input[type="file"]:focus { border-color: var(--accent); outline: none; }
input[type="file"]::file-selector-button {
  background: var(--accent);
  color: #fff;
  border: none;
  border-radius: 6px;
  padding: 7px 14px;
  margin-right: 12px;
  cursor: pointer;
  font-size: 0.85rem;
  font-weight: 500;
  font-family: inherit;
  transition: background 0.2s;
}
input[type="file"]::file-selector-button:hover { background: #3d7ae6; }

.checkbox-row {
  display: flex;
  align-items: center;
  gap: 8px;
}
.checkbox-row input[type="checkbox"] {
  width: auto;
  accent-color: var(--accent);
  cursor: pointer;
}

/* ── Auth page ── */
.auth-wrap {
  display: flex;
  justify-content: center;
  align-items: center;
  min-height: 90vh;
}
.auth-box {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 16px;
  padding: 40px 36px;
  width: 100%;
  max-width: 380px;
}
.auth-box h2 { margin: 0 0 24px; font-size: 1.4rem; text-align: center; }
.auth-error { color: var(--danger); font-size: 0.9rem; margin-top: 12px; text-align: center; }

/* ── Task editor ── */
.task-layout {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 20px;
  max-width: 1200px;
  margin: 24px auto;
  padding: 0 16px;
}
@media (max-width: 900px) { .task-layout { grid-template-columns: 1fr; } }

.task-desc { background: var(--card); border: 1px solid var(--border); border-radius: 12px; padding: 24px; }
.task-desc h2 { margin-top: 0; }

.task-editor-panel {
  display: flex;
  flex-direction: column;
  gap: 12px;
}
#ace-editor {
  height: 380px;
  border-radius: 8px;
  border: 1.5px solid var(--border);
  overflow: hidden;
}

.submission-status {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 14px 16px;
  min-height: 52px;
  display: flex;
  align-items: center;
  gap: 10px;
}

.test-cases { margin-top: 12px; }
.test-case {
  background: #1a1d24;
  border-radius: 8px;
  padding: 10px 14px;
  margin-bottom: 8px;
  font-size: 0.88rem;
}
.test-case-label { color: var(--muted); font-size: 0.78rem; margin-bottom: 4px; }
.test-case pre { margin: 0; white-space: pre-wrap; word-break: break-all; }

.history-item {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 8px;
  border-bottom: 1px solid var(--border);
  border-radius: 6px;
  font-size: 0.88rem;
  cursor: pointer;
  transition: background 0.15s, box-shadow 0.15s;
}
.history-item:hover { color: var(--accent); background: rgba(79,140,255,0.05); }
.history-item.active {
  background: rgba(79,140,255,0.12);
  box-shadow: inset 3px 0 0 var(--accent);
}

/* ── Profile ── */
.profile-header {
  display: flex;
  align-items: center;
  gap: 20px;
  margin-bottom: 24px;
}
.profile-avatar {
  width: 64px; height: 64px;
  border-radius: 50%;
  border: 2px solid var(--accent);
}
.profile-stats {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 12px;
  margin-bottom: 24px;
}
.stat-box {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 16px;
  text-align: center;
}
.stat-value { font-size: 1.6rem; font-weight: 700; color: var(--accent); }
.stat-label { font-size: 0.8rem; color: var(--muted); margin-top: 4px; }

.emoji-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(90px, 1fr));
  gap: 10px;
  margin-top: 12px;
}
.emoji-card {
  background: var(--card);
  border: 1.5px solid var(--border);
  border-radius: 10px;
  padding: 12px 8px;
  text-align: center;
  cursor: pointer;
  transition: all 0.2s;
}
.emoji-card.available:hover { border-color: var(--accent); transform: translateY(-2px); }
.emoji-card.locked { opacity: 0.45; cursor: default; }
.emoji-card.active { border-color: var(--accent); background: rgba(79,140,255,0.1); }
.emoji-icon { font-size: 2rem; }
.emoji-need { font-size: 0.75rem; color: var(--muted); margin-top: 4px; }

/* ── Admin panel ── */
.admin-wrap {
  max-width: 1100px;
  margin: 24px auto;
  padding: 0 16px;
}
.admin-tabs {
  display: flex;
  gap: 4px;
  margin-bottom: 24px;
  flex-wrap: wrap;
}
.tab-btn {
  padding: 8px 18px;
  border-radius: 8px;
  border: 1.5px solid var(--border);
  background: transparent;
  color: var(--muted);
  cursor: pointer;
  font-size: 0.9rem;
  transition: all 0.2s;
}
.tab-btn.active, .tab-btn:hover { border-color: var(--accent); color: var(--text); background: rgba(79,140,255,0.08); }
.tab-content { display: none; }
.tab-content.active { display: block; }

.admin-section-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 16px;
}
.admin-section-header h3 { margin: 0; }

table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.9rem;
}
th {
  text-align: left;
  color: var(--muted);
  padding: 8px 10px;
  border-bottom: 1px solid var(--border);
  font-weight: 500;
}
td {
  padding: 10px 10px;
  border-bottom: 1px solid var(--border);
  vertical-align: middle;
}
tr:hover td { background: rgba(255,255,255,0.02); }

/* ── Modal ── */
.modal-backdrop {
  display: none;
  position: fixed;
  inset: 0;
  background: rgba(0,0,0,0.6);
  z-index: 100;
  justify-content: center;
  align-items: center;
}
.modal-backdrop.open { display: flex; }
.modal {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 14px;
  padding: 28px 28px 24px;
  width: 100%;
  max-width: 520px;
  max-height: 90vh;
  overflow-y: auto;
}
.modal h3 { margin: 0 0 20px; }
.modal-footer {
  display: flex;
  justify-content: flex-end;
  gap: 8px;
  margin-top: 20px;
}

/* ── Stats grid ── */
.stats-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(160px, 1fr));
  gap: 12px;
  margin-bottom: 24px;
}

/* ── Misc ── */
.text-muted { color: var(--muted); }
.text-success { color: var(--success); }
.text-danger { color: var(--danger); }
.text-accent { color: var(--accent); }
.mb-0 { margin-bottom: 0; }
.mt-16 { margin-top: 16px; }
.flex { display: flex; }
.gap-8 { gap: 8px; }
.align-center { align-items: center; }
.justify-between { justify-content: space-between; }
.spinner {
  width: 18px; height: 18px;
  border: 2px solid var(--border);
  border-top-color: var(--accent);
  border-radius: 50%;
  animation: spin 0.7s linear infinite;
  display: inline-block;
}
@keyframes spin { to { transform: rotate(360deg); } }

/* Таблицы: не сжимаются в кашу, а скроллятся горизонтально внутри карточки */
@media (max-width: 700px) {
  table { min-width: 520px; }
}

@media (max-width: 600px) {
  .container { padding: 0 8px; }
  .auth-box { padding: 28px 16px; }
  .profile-stats { grid-template-columns: repeat(2, 1fr); }
  .admin-tabs { gap: 4px; }
  .tab-btn { padding: 6px 10px; font-size: 0.8rem; }

  /* Шапка компактнее */
  .header { padding: 10px 14px; }
  .header h1 { font-size: 1.05rem; }
  .user-info { gap: 7px; font-size: 0.88rem; }
  .avatar { width: 28px; height: 28px; }
  .admin-btn { padding: 5px 10px; font-size: 0.78rem; }

  /* Модалки во весь экран по ширине, меньше отступы */
  .modal { padding: 20px 16px; max-width: 100%; }
  .modal-footer { flex-wrap: wrap; }

  /* Редактор кода ниже на мобильном */
  #ace-editor { height: 320px !important; }

  /* Статистика админки в 2 колонки */
  .stats-grid { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 400px) {
  .profile-stats { grid-template-columns: 1fr; }
  .header h1 { font-size: 0.95rem; }
}