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

:root {
  --bg: #0f0f0f;
  --surface: #1a1a1a;
  --surface-2: #252525;
  --border: #2e2e2e;
  --text: #f0f0f0;
  --text-muted: #888;
  --accent: #ff6b35;
  --accent-glow: rgba(255, 107, 53, 0.3);
  --success: #4caf50;
  --danger: #e53935;
  --radius: 16px;
  --radius-sm: 8px;
}

html {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', system-ui, sans-serif;
  background: var(--bg);
  color: var(--text);
  min-height: 100vh;
}

body {
  min-height: 100vh;
  display: flex;
  justify-content: center;
  align-items: flex-start;
  padding: 24px 16px 48px;
}

/* ── Auth view ───────────────────────────────────────────────────── */

.auth-wrapper {
  position: fixed;
  inset: 0;
  display: grid;
  place-items: center;
  padding: 16px;
  overflow-y: auto;
  background: var(--bg);
  z-index: 10;
}

.auth-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 36px 28px 32px;
  display: flex;
  flex-direction: column;
  gap: 20px;
  width: 100%;
  max-width: 400px;
}

.auth-tagline {
  font-size: 0.9rem;
  color: var(--text-muted);
  margin-top: -12px;
  text-align: center;
}

.tab-row {
  display: flex;
  background: var(--surface-2);
  border-radius: var(--radius-sm);
  padding: 3px;
  gap: 3px;
}

.tab {
  flex: 1;
  background: none;
  border: none;
  color: var(--text-muted);
  font-size: 0.9rem;
  font-weight: 500;
  padding: 8px 12px;
  border-radius: calc(var(--radius-sm) - 2px);
  cursor: pointer;
  transition: background 0.2s, color 0.2s;
}

.tab.active {
  background: var(--surface);
  color: var(--text);
  box-shadow: 0 1px 4px rgba(0,0,0,0.4);
}

.field {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.field label {
  font-size: 0.82rem;
  font-weight: 500;
  color: var(--text-muted);
  display: flex;
  align-items: center;
  gap: 6px;
}

.field-optional {
  font-size: 0.75rem;
  font-weight: 400;
  color: var(--text-muted);
  opacity: 0.7;
}

.field input {
  background: var(--surface-2);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  color: var(--text);
  font-size: 1rem;
  padding: 11px 14px;
  outline: none;
  transition: border-color 0.2s;
  width: 100%;
}

.field input:focus {
  border-color: var(--accent);
}

.auth-error {
  font-size: 0.85rem;
  color: var(--danger);
  text-align: center;
  min-height: 1.2em;
}

/* ── App view ────────────────────────────────────────────────────── */

.container {
  width: 100%;
  max-width: 480px;
  display: flex;
  flex-direction: column;
  gap: 24px;
}

header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-top: 8px;
}

.app-title {
  font-size: 1rem;
  font-weight: 600;
  letter-spacing: 0.15em;
  text-transform: uppercase;
  color: var(--text-muted);
}

.user-row {
  display: flex;
  align-items: center;
  gap: 10px;
}

.username-badge {
  font-size: 0.82rem;
  color: var(--text-muted);
}

.logout-btn {
  background: none;
  border: 1px solid var(--border);
  color: var(--text-muted);
  font-size: 0.78rem;
  padding: 5px 10px;
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: color 0.2s, border-color 0.2s;
}

.logout-btn:hover {
  color: var(--text);
  border-color: var(--text-muted);
}

/* Nickname dialog */
dialog {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  color: var(--text);
  padding: 28px;
  width: min(400px, calc(100vw - 32px));
}

dialog::backdrop {
  background: rgba(0, 0, 0, 0.65);
  backdrop-filter: blur(3px);
}

.dialog-title {
  font-size: 1.05rem;
  font-weight: 700;
  margin-bottom: 20px;
}

.dialog-hint {
  font-size: 0.8rem;
  color: var(--text-muted);
  margin-top: 8px;
}

.dialog-actions {
  display: flex;
  gap: 8px;
  margin-top: 20px;
  justify-content: flex-end;
}

.dialog-cancel {
  background: var(--surface-2);
  border: 1px solid var(--border);
  color: var(--text-muted);
  font-size: 0.9rem;
  font-weight: 500;
  padding: 10px 18px;
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: color 0.2s;
}

.dialog-cancel:hover {
  color: var(--text);
}

.dialog-save {
  width: auto;
  padding: 10px 22px;
  font-size: 0.9rem;
  box-shadow: none;
}

/* Hero */
.streak-hero {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
  padding: 32px 24px 24px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
}

.flame-wrapper {
  width: 72px;
  height: 90px;
  margin-bottom: 4px;
}

.flame {
  width: 100%;
  height: 100%;
  transition: filter 0.4s ease, opacity 0.4s ease;
}

.flame.inactive {
  filter: grayscale(1);
  opacity: 0.3;
}

.flame.active {
  filter: drop-shadow(0 0 16px var(--accent-glow));
  animation: flicker 2.5s ease-in-out infinite;
}

@keyframes flicker {
  0%, 100% { transform: scaleX(1) scaleY(1); }
  25%       { transform: scaleX(0.97) scaleY(1.02); }
  50%       { transform: scaleX(1.02) scaleY(0.98); }
  75%       { transform: scaleX(0.99) scaleY(1.01); }
}

.streak-count-wrapper {
  display: flex;
  align-items: baseline;
  gap: 10px;
}

.streak-number {
  font-size: 5rem;
  font-weight: 800;
  line-height: 1;
  letter-spacing: -0.03em;
  color: var(--text);
  transition: color 0.3s;
}

.streak-number.has-streak {
  color: var(--accent);
}

.streak-label {
  font-size: 1.1rem;
  font-weight: 500;
  color: var(--text-muted);
}

.streak-status {
  font-size: 0.9rem;
  color: var(--text-muted);
  text-align: center;
  min-height: 1.4em;
}

/* Action area */
.action-area {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 12px;
}

.checkin-btn {
  width: 100%;
  padding: 18px 24px;
  font-size: 1.1rem;
  font-weight: 700;
  letter-spacing: 0.02em;
  color: #fff;
  background: var(--accent);
  border: none;
  border-radius: var(--radius);
  cursor: pointer;
  transition: background 0.2s, transform 0.15s, box-shadow 0.2s;
  box-shadow: 0 4px 20px var(--accent-glow);
}

.checkin-btn:hover:not(:disabled) {
  background: #ff7f4f;
  transform: translateY(-2px);
  box-shadow: 0 6px 28px var(--accent-glow);
}

.checkin-btn:active:not(:disabled) {
  transform: translateY(0);
}

.checkin-btn:disabled,
.checkin-btn.done {
  background: var(--surface-2);
  color: var(--success);
  box-shadow: none;
  cursor: default;
  border: 1px solid var(--border);
}

.checkin-btn[data-loading] {
  opacity: 0.6;
  cursor: wait;
}

.reset-warning {
  font-size: 0.85rem;
  color: var(--danger);
  text-align: center;
}

/* Stats */
.stats-row {
  display: flex;
  align-items: center;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
}

.stat {
  flex: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 4px;
  padding: 20px 16px;
}

.stat-value {
  font-size: 1.8rem;
  font-weight: 700;
  color: var(--text);
}

.stat-label {
  font-size: 0.78rem;
  color: var(--text-muted);
  text-align: center;
  line-height: 1.3;
}

.stat-divider {
  width: 1px;
  height: 48px;
  background: var(--border);
}

/* Calendar */
.calendar-section {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 20px;
  display: flex;
  flex-direction: column;
  gap: 14px;
}

.calendar-title {
  font-size: 0.8rem;
  font-weight: 600;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--text-muted);
}

.calendar-grid {
  display: grid;
  grid-template-columns: repeat(10, 1fr);
  gap: 5px;
}

.cal-day {
  aspect-ratio: 1;
  border-radius: 4px;
  background: var(--surface-2);
  border: 1px solid var(--border);
  position: relative;
  cursor: default;
  transition: background 0.2s;
}

.cal-day.checked {
  background: var(--accent);
  border-color: var(--accent);
}

.cal-day.today {
  border-color: var(--text-muted);
}

.cal-day.today.checked {
  border-color: #ffd700;
  box-shadow: 0 0 6px rgba(255, 215, 0, 0.4);
}

.cal-day[data-tooltip]:hover::after {
  content: attr(data-tooltip);
  position: absolute;
  bottom: calc(100% + 6px);
  left: 50%;
  transform: translateX(-50%);
  background: #333;
  color: var(--text);
  font-size: 0.72rem;
  padding: 4px 8px;
  border-radius: 4px;
  white-space: nowrap;
  pointer-events: none;
  z-index: 10;
}

/* Leaderboard */
.leaderboard-section {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 20px;
  display: flex;
  flex-direction: column;
  gap: 14px;
}

.leaderboard-list {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.lb-row {
  display: grid;
  grid-template-columns: 32px 1fr auto;
  align-items: center;
  gap: 10px;
  padding: 10px 12px;
  border-radius: var(--radius-sm);
  background: var(--surface-2);
  border: 1px solid transparent;
  transition: border-color 0.2s;
}

.lb-row.lb-you {
  border-color: var(--accent);
  background: rgba(255, 107, 53, 0.07);
}

.lb-rank {
  font-size: 1rem;
  text-align: center;
  line-height: 1;
  min-width: 24px;
}

.lb-name {
  font-size: 0.92rem;
  font-weight: 500;
  color: var(--text);
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.lb-you .lb-name::after {
  content: ' (du)';
  font-size: 0.78rem;
  color: var(--accent);
  font-weight: 400;
}

.lb-streak {
  display: flex;
  align-items: center;
  gap: 5px;
  font-size: 0.88rem;
  font-weight: 700;
  color: var(--text);
  white-space: nowrap;
}

.lb-streak .lb-fire {
  font-size: 0.85rem;
}

.lb-empty {
  font-size: 0.85rem;
  color: var(--text-muted);
  text-align: center;
  padding: 16px 0;
}

/* Footer */

.reset-btn {
  background: none;
  border: none;
  color: var(--text-muted);
  font-size: 0.8rem;
  cursor: pointer;
  padding: 8px 12px;
  border-radius: var(--radius-sm);
  transition: color 0.2s;
  text-decoration: underline;
  text-underline-offset: 3px;
}

.reset-btn:hover {
  color: var(--text);
}

.reset-btn.danger:hover {
  color: var(--danger);
}

footer {
  display: flex;
  justify-content: center;
  gap: 8px;
}

/* Toast */
.toast {
  position: fixed;
  bottom: 32px;
  left: 50%;
  transform: translateX(-50%) translateY(20px);
  background: var(--surface-2);
  color: var(--text);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 12px 20px;
  font-size: 0.9rem;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.25s, transform 0.25s;
  z-index: 100;
  white-space: nowrap;
}

.toast.show {
  opacity: 1;
  transform: translateX(-50%) translateY(0);
}

/* Pop animation */
@keyframes pop {
  0%   { transform: scale(1); }
  50%  { transform: scale(1.06); }
  100% { transform: scale(1); }
}

.streak-number.pop {
  animation: pop 0.35s ease;
}

@media (max-width: 360px) {
  .streak-number { font-size: 4rem; }
  .calendar-grid { grid-template-columns: repeat(7, 1fr); }
}