@import url('https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600;700;800&display=swap');

*, *::before, *::after { margin: 0; padding: 0; box-sizing: border-box; }

body {
  min-height: 100vh;
  color: #f8fafc;
  font-family: 'Inter', sans-serif;
  background:
    radial-gradient(circle at top left, rgba(37,99,235,0.18), transparent 30%),
    #050505;
}

a { color: inherit; text-decoration: none; }
button { font: inherit; cursor: pointer; }

/* ── Page ──────────────────────────────────────────────── */
.problems-page {
  width: min(860px, calc(100% - 32px));
  margin: 0 auto;
  padding: 48px 0 80px;
}

/* ── Daily Challenge Card ──────────────────────────────── */
.daily-card {
  position: relative;
  overflow: hidden;
  margin-bottom: 28px;
  padding: 28px 32px;
  border-radius: 14px;
  border: 1px solid rgba(96,165,250,0.25);
  background: linear-gradient(135deg, rgba(37,99,235,0.18) 0%, rgba(14,165,233,0.1) 100%);
}

.daily-card::before {
  content: '';
  position: absolute;
  inset: 0;
  background: radial-gradient(ellipse at top right, rgba(96,165,250,0.12), transparent 60%);
  pointer-events: none;
}

.daily-loading {
  color: #64748b;
  font-size: 14px;
}

.daily-inner {
  display: flex;
  align-items: center;
  gap: 24px;
  flex-wrap: wrap;
}

.daily-left {
  flex: 1;
  min-width: 0;
}

.daily-kicker {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 10px;
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: #93c5fd;
}

.daily-kicker svg { flex-shrink: 0; }

.daily-streak {
  padding: 2px 8px;
  border-radius: 4px;
  background: rgba(251,146,60,0.15);
  color: #fb923c;
  font-size: 11px;
  font-weight: 700;
}

.daily-title {
  font-size: 22px;
  font-weight: 700;
  line-height: 1.3;
  margin-bottom: 12px;
  color: #f1f5f9;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.daily-tags {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
}

.daily-tags span {
  padding: 3px 10px;
  border-radius: 5px;
  font-size: 12px;
  font-weight: 600;
  border: 1px solid rgba(255,255,255,0.1);
  color: #cbd5e1;
  background: rgba(255,255,255,0.05);
}

.daily-tags .easy   { color: #86efac; border-color: rgba(134,239,172,0.3); background: rgba(134,239,172,0.08); }
.daily-tags .medium { color: #fde047; border-color: rgba(253,224,71,0.3);  background: rgba(253,224,71,0.08); }
.daily-tags .hard   { color: #f87171; border-color: rgba(248,113,113,0.3); background: rgba(248,113,113,0.08); }

.daily-solved-badge {
  padding: 3px 10px;
  border-radius: 5px;
  font-size: 12px;
  font-weight: 700;
  color: #86efac;
  border: 1px solid rgba(134,239,172,0.35);
  background: rgba(134,239,172,0.1);
}

.daily-solve-btn {
  flex-shrink: 0;
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 12px 22px;
  border-radius: 10px;
  border: none;
  background: #2563eb;
  color: #fff;
  font-size: 14px;
  font-weight: 700;
  text-decoration: none;
  transition: background 0.2s, transform 0.15s;
  white-space: nowrap;
}

.daily-solve-btn:hover { background: #3b82f6; transform: translateY(-1px); }
.daily-solve-btn.solved { background: rgba(134,239,172,0.15); color: #86efac; border: 1px solid rgba(134,239,172,0.3); }
.daily-solve-btn svg { flex-shrink: 0; }

/* ── Panel ─────────────────────────────────────────────── */
.problems-panel {
  border: 1px solid rgba(255,255,255,0.08);
  border-radius: 14px;
  background: rgba(255,255,255,0.02);
  overflow: hidden;
}

/* ── Filters ───────────────────────────────────────────── */
.panel-filters {
  padding: 20px 20px 16px;
  border-bottom: 1px solid rgba(255,255,255,0.07);
}

.search-wrap {
  position: relative;
  margin-bottom: 14px;
}

.search-icon {
  position: absolute;
  left: 12px;
  top: 50%;
  transform: translateY(-50%);
  width: 16px;
  height: 16px;
  pointer-events: none;
}

.search-input {
  width: 100%;
  padding: 10px 36px 10px 36px;
  border: 1px solid rgba(255,255,255,0.09);
  border-radius: 8px;
  background: rgba(255,255,255,0.04);
  color: #f8fafc;
  font-size: 14px;
  outline: none;
  transition: border-color 0.2s;
}

.search-input:focus { border-color: rgba(96,165,250,0.5); }
.search-input::placeholder { color: #475569; }

.search-clear {
  position: absolute;
  right: 10px;
  top: 50%;
  transform: translateY(-50%);
  padding: 2px 6px;
  border: none;
  background: none;
  color: #475569;
  font-size: 12px;
  display: none;
}

.search-clear.visible { display: block; }
.search-clear:hover { color: #94a3b8; }

.filter-row {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
  align-items: flex-start;
}

/* difficulty pills */
.diff-group {
  display: flex;
  gap: 4px;
  flex-shrink: 0;
}

.diff-btn {
  padding: 5px 13px;
  border: 1px solid rgba(255,255,255,0.09);
  border-radius: 6px;
  background: transparent;
  color: #64748b;
  font-size: 12px;
  font-weight: 600;
  transition: all 0.15s;
}

.diff-btn:hover { color: #cbd5e1; border-color: rgba(255,255,255,0.18); }

.diff-btn.active       { color: #f8fafc; background: rgba(96,165,250,0.15); border-color: rgba(96,165,250,0.4); }
.diff-btn.easy.active  { color: #86efac; background: rgba(134,239,172,0.12); border-color: rgba(134,239,172,0.4); }
.diff-btn.medium.active{ color: #fde047; background: rgba(253,224,71,0.12);  border-color: rgba(253,224,71,0.4); }
.diff-btn.hard.active  { color: #f87171; background: rgba(248,113,113,0.12); border-color: rgba(248,113,113,0.4); }

/* tag scroll strip */
.tag-scroll {
  display: flex;
  gap: 5px;
  flex-wrap: wrap;
  flex: 1;
  min-width: 0;
}

.tag-btn {
  padding: 5px 11px;
  border: 1px solid rgba(255,255,255,0.07);
  border-radius: 20px;
  background: transparent;
  color: #475569;
  font-size: 11px;
  font-weight: 600;
  white-space: nowrap;
  transition: all 0.15s;
}

.tag-btn:hover { color: #94a3b8; border-color: rgba(255,255,255,0.15); }
.tag-btn.active { color: #60a5fa; background: rgba(96,165,250,0.1); border-color: rgba(96,165,250,0.3); }

.results-meta {
  margin-top: 10px;
  font-size: 12px;
  color: #475569;
}

/* ── Table head ────────────────────────────────────────── */
.prob-table-head {
  display: grid;
  grid-template-columns: 32px 44px 1fr 180px 90px;
  gap: 0;
  padding: 10px 20px;
  border-bottom: 1px solid rgba(255,255,255,0.07);
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: #475569;
}

/* ── Table rows ────────────────────────────────────────── */
.prob-table-body { }

.prob-row {
  display: grid;
  grid-template-columns: 32px 44px 1fr 180px 90px;
  gap: 0;
  padding: 0 20px;
  min-height: 48px;
  align-items: center;
  border-bottom: 1px solid rgba(255,255,255,0.04);
  transition: background 0.12s;
  cursor: pointer;
  text-decoration: none;
  color: inherit;
}

.prob-row:last-child { border-bottom: none; }
.prob-row:hover { background: rgba(255,255,255,0.04); }
.prob-row.is-daily { background: rgba(37,99,235,0.06); }
.prob-row.is-daily:hover { background: rgba(37,99,235,0.1); }

.col-status {
  display: flex;
  align-items: center;
  justify-content: center;
}

.status-icon {
  width: 16px;
  height: 16px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 10px;
  font-weight: 800;
  flex-shrink: 0;
}

.status-icon.solved   { background: rgba(134,239,172,0.15); color: #86efac; }
.status-icon.unsolved { background: rgba(255,255,255,0.05); color: #334155; }

.col-num {
  font-size: 12px;
  color: #475569;
  font-weight: 500;
}

.col-title {
  display: flex;
  align-items: center;
  gap: 6px;
  min-width: 0;
}

.row-title {
  font-size: 14px;
  font-weight: 500;
  color: #e2e8f0;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.prob-row:hover .row-title { color: #f8fafc; }

.daily-dot {
  flex-shrink: 0;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: #60a5fa;
}

.col-tags {
  display: flex;
  gap: 4px;
  flex-wrap: nowrap;
  overflow: hidden;
  min-width: 0;
}

.row-tag {
  padding: 2px 8px;
  border-radius: 4px;
  font-size: 11px;
  font-weight: 500;
  color: #64748b;
  background: rgba(255,255,255,0.05);
  border: 1px solid rgba(255,255,255,0.06);
  white-space: nowrap;
  flex-shrink: 0;
}

.row-tag-more {
  font-size: 11px;
  color: #475569;
  flex-shrink: 0;
}

.col-diff {
  display: flex;
  align-items: center;
}

.diff-badge {
  padding: 3px 9px;
  border-radius: 5px;
  font-size: 12px;
  font-weight: 600;
}

.diff-badge.easy   { color: #86efac; background: rgba(134,239,172,0.1); }
.diff-badge.medium { color: #fde047; background: rgba(253,224,71,0.1);  }
.diff-badge.hard   { color: #f87171; background: rgba(248,113,113,0.1); }

.prob-empty {
  padding: 48px 20px;
  text-align: center;
  color: #475569;
  font-size: 14px;
}

/* ── Responsive ────────────────────────────────────────── */
@media (max-width: 640px) {
  .problems-page { padding: 32px 0 60px; }

  .prob-table-head,
  .prob-row {
    grid-template-columns: 28px 36px 1fr 80px;
  }

  .col-tags { display: none; }
  .prob-table-head .col-tags { display: none; }

  .daily-title { font-size: 17px; }
  .daily-solve-btn { padding: 10px 16px; font-size: 13px; }

  .diff-group { gap: 3px; }
  .diff-btn { padding: 4px 9px; font-size: 11px; }
}