/* stat cards */
.stats-board { display: grid; grid-template-columns: repeat(auto-fit, minmax(140px, 1fr)); gap: 12px; margin-bottom: 12px; }
.stat-card {
  background: linear-gradient(135deg, rgba(var(--accent-rgb), 0.12), var(--easy-bg));
  border: 1px solid rgba(var(--accent-rgb), 0.3);
  border-radius: 12px;
  padding: 16px 18px;
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  box-shadow: 0 4px 16px var(--shadow-sm);
  transition: border-color 0.25s, transform 0.25s, box-shadow 0.25s;
}
.stat-card:hover {
  border-color: rgba(var(--accent-rgb), 0.4);
  transform: translateY(-3px);
  box-shadow: 0 8px 24px var(--shadow-md);
}
.stat-label { font-family: 'JetBrains Mono', monospace; font-size: 10px; text-transform: uppercase; letter-spacing: 0.1em; color: var(--text-muted); margin-bottom: 8px; }
.stat-value { font-size: 28px; font-weight: 800; line-height: 1; letter-spacing: -0.03em; }
.stat-value.total  { color: var(--accent); }
.stat-value.easy   { color: var(--easy); }
.stat-value.medium { color: var(--medium); }
.stat-value.hard   { color: var(--hard); }
.stat-sub { font-size: 11px; color: var(--text-muted); margin-top: 4px; font-family: 'JetBrains Mono', monospace; }

/* overall progress bar */
.global-progress { background: linear-gradient(135deg, rgba(var(--accent-rgb), 0.12), var(--easy-bg)); border: 1px solid rgba(var(--accent-rgb), 0.3); border-radius: 12px; padding: 20px 24px; margin-bottom: 12px; backdrop-filter: blur(8px); -webkit-backdrop-filter: blur(8px); box-shadow: 0 4px 16px var(--shadow-sm); }
.progress-header { display: flex; justify-content: space-between; align-items: center; margin-bottom: 12px; }
.progress-title { font-size: 13px; font-weight: 600; color: var(--text-dim); text-transform: uppercase; letter-spacing: 0.08em; }
.progress-pct { font-family: 'JetBrains Mono', monospace; font-size: 13px; color: var(--accent); }
.progress-track { height: 8px; background: var(--surface3); border-radius: 999px; overflow: hidden; display: flex; }
.easy-fill   { background: var(--easy);   transition: width 0.8s cubic-bezier(0.4,0,0.2,1); position: relative; overflow: hidden; }
.medium-fill { background: var(--medium); transition: width 0.8s cubic-bezier(0.4,0,0.2,1) 0.1s; position: relative; overflow: hidden; }
.hard-fill   { background: var(--hard);   transition: width 0.8s cubic-bezier(0.4,0,0.2,1) 0.2s; position: relative; overflow: hidden; }
.easy-fill::after, .medium-fill::after, .hard-fill::after {
  content: ''; position: absolute; inset: 0;
  background: linear-gradient(90deg, transparent 0%, rgba(255,255,255,0.3) 50%, transparent 100%);
  animation: progressSweep 1s ease-out 1s 1 both;
}
@keyframes progressSweep {
  from { transform: translateX(-100%); }
  to   { transform: translateX(100%); opacity: 0; }
}

/* top stats (today & streak) */
.top-stats {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
  gap: 16px;
  margin-bottom: 12px;
}

.top-stats .stat-card {
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  text-align: center;
  padding: 24px 20px;
  background: var(--surface2);
  border: 1px solid var(--border);
  box-shadow: 0 4px 20px rgba(0,0,0,0.2);
}

.top-stats .stat-value {
  font-size: 44px;
  margin: 8px 0;
  text-shadow: 0 2px 10px rgba(0,0,0,0.5);
  transition: color 0.3s, text-shadow 0.3s;
}

[data-theme="light"] .top-stats .stat-value {
  text-shadow: 0 2px 8px rgba(0,0,0,0.12);
}

[data-theme="light"] .stat-card:hover {
  box-shadow: 0 8px 24px rgba(0,0,0,0.08);
}
[data-theme="light"] .top-stats .stat-card {
  box-shadow: 0 2px 12px rgba(0,0,0,0.06);
}
[data-theme="light"] .streak-active {
  text-shadow: none;
}
[data-theme="light"] .today-active {
  text-shadow: none;
}

/* Base states: dim unless active */
.streak-val { color: var(--text-dim); }
.today-val  { color: var(--text-dim); }

/* Streak heartbeat when active */
@keyframes heartbeat {
  0%   { transform: scale(1); }
  14%  { transform: scale(1.06); }
  28%  { transform: scale(1); }
  42%  { transform: scale(1.04); }
  70%  { transform: scale(1); }
  100% { transform: scale(1); }
}
.streak-active {
  color: var(--orange);
  text-shadow: 0 0 20px rgba(var(--orange-rgb), 0.4);
  animation: heartbeat 2.4s ease-in-out infinite;
  display: inline-block;
}

.today-active {
  color: var(--easy);
  text-shadow: 0 0 20px rgba(var(--easy-rgb), 0.4);
}

.today-track {
  width: 100%;
  max-width: 120px;
  height: 6px;
  margin-top: 12px;
  background: var(--surface3);
}

/* loading skeleton for stat cards */
/* Applied while body.loading — removed by updateStats() when real data arrives */
body.loading .stat-value,
body.loading .stat-sub {
  color: transparent !important;
  -webkit-text-fill-color: transparent !important;
  text-shadow: none !important;
  animation: none !important;
  background: var(--surface2);
  border-radius: 5px;
  position: relative;
  overflow: hidden;
  display: block;
}
body.loading .stat-value::after,
body.loading .stat-sub::after {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(90deg, transparent 25%, rgba(255,255,255,0.06) 50%, transparent 75%);
  background-size: 200% 100%;
  animation: shimmer 1.5s infinite linear;
}
body.loading .progress-track { opacity: 0.15; }
[data-theme="light"] body.loading .stat-value::after,
[data-theme="light"] body.loading .stat-sub::after {
  background: linear-gradient(90deg, transparent 25%, rgba(0,0,0,0.04) 50%, transparent 75%);
  background-size: 200% 100%;
}
body.loading #prog-pct        { visibility: hidden; }