:root {
  --bg-color: #0f172a;
  --bg-rgb: 15, 23, 42;
  --bg-alpha: 0.15;
  --panel: rgba(17, 24, 39, 0.98);
  --panel-radius: 28px;
  --panel-blur: 0px;

  --surface: #1f2937;
  --surface-strong: #374151;
  --text: #e2e8f0;
  --text-color: #e2e8f0;
  --muted: #94a3b8;
  --primary: #38bdf8;
  --danger: #f87171;
  --border: rgba(148, 163, 184, 0.2);
}

* {
  box-sizing: border-box;
}

html, body {
  margin: 0;
  min-height: 100%;
  background: radial-gradient(circle at top, rgba(var(--bg-rgb), var(--bg-alpha)), transparent 35%),
              linear-gradient(180deg, var(--bg-color) 0%, var(--bg-color) 100%);
  color: var(--text);
  font-family: Inter, system-ui, -apple-system, BlinkMacSystemFont, sans-serif;
}

.confetti-container {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  pointer-events: none;
  overflow: hidden;
  z-index: 9999;
}

.confetti-piece {
  position: fixed;
  pointer-events: none;
  font-size: 2rem;
}

@keyframes confetti-fall {
  0% {
    transform: translateY(0) rotateZ(0deg);
    opacity: 1;
  }
  80% {
    transform: translateY(80vh) rotateZ(288deg);
    opacity: 1;
  }
  to {
    transform: translateY(100vh) rotateZ(360deg);
    opacity: 0;
  }
}

body {
  min-height: 100vh;
  padding: 1rem;
  display: flex;
  align-items: center;
  justify-content: center;
}

.app-shell {
  width: 100%;
  max-width: 640px;
}

.todo-panel {
  width: 100%;
  max-width: 640px;
  margin: 0 auto;
  background: var(--panel);
  border: 1px solid rgba(255, 255, 255, 0.08);
  border-radius: var(--panel-radius);
  padding: 2rem;
  box-shadow: 0 32px 80px rgba(0,0,0,0.18);
  backdrop-filter: blur(var(--panel-blur));
}

.fab {
  position: fixed;
  right: 1rem;
  bottom: 1rem;
  border: none;
  border-radius: 999px;
  padding: 0.9rem 1.2rem;
  background: var(--primary);
  color: #030712;
  font-weight: 700;
  cursor: pointer;
  box-shadow: 0 18px 28px rgba(0,0,0,0.2);
  z-index: 10;
}

.fab.hidden {
  display: none;
}

.todo-popup {
  position: fixed;
  right: 1rem;
  bottom: 1rem;
  width: min(380px, 92vw);
  max-height: 92vh;
  padding: 1.5rem;
  display: flex;
  flex-direction: column;
  gap: 1rem;
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: var(--panel-radius);
  box-shadow: 0 32px 90px rgba(0,0,0,0.25);
  backdrop-filter: blur(var(--panel-blur));
  overflow: hidden;
  z-index: 11;
}

.todo-popup.hidden {
  display: none;
}

.popup-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 1rem;
}

.popup-header h1 {
  margin: 0;
  font-size: 1.2rem;
}

.popup-header p {
  margin: 0.35rem 0 0;
  color: var(--text);
  font-size: 0.95rem;
}

.icon-button {
  border: none;
  border-radius: 999px;
  width: 2.6rem;
  height: 2.6rem;
  background: rgba(255,255,255,0.08);
  color: var(--text);
  font-size: 1.2rem;
  cursor: pointer;
}

.settings-panel {
  display: grid;
  gap: 0.9rem;
  padding: 1rem;
  background: rgba(15, 23, 42, 0.75);
  border: 1px solid rgba(148, 163, 184, 0.14);
  border-radius: 22px;
}

.settings-panel h2 {
  margin: 0;
  font-size: 1rem;
  color: var(--text);
}

.slider-row {
  display: grid;
  gap: 0.5rem;
}

.slider-row label {
  color: var(--text);
  font-size: 0.93rem;
}

.slider-row input[type="range"],
.slider-row input[type="color"] {
  width: 100%;
  accent-color: var(--primary);
  border-radius: 999px;
  height: 2rem;
}

.todo-form {
  display: flex;
  gap: 0.75rem;
}

.todo-form input {
  flex: 1;
  border: 1px solid var(--border);
  border-radius: 999px;
  padding: 1rem 1.25rem;
  background: var(--surface);
  color: var(--text);
  font-size: 1rem;
}

.todo-form button {
  border: none;
  border-radius: 999px;
  padding: 1rem 1.4rem;
  background: var(--primary);
  color: #030712;
  font-weight: 700;
  cursor: pointer;
  transition: transform 0.2s ease, background 0.2s ease;
}

.todo-form button:hover {
  transform: translateY(-1px);
}

.todo-controls {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 1rem;
  flex-wrap: wrap;
}

.status-pill {
  padding: 0.75rem 1rem;
  border-radius: 999px;
  background: rgba(148, 163, 184, 0.12);
  color: var(--text);
  font-size: 0.95rem;
}

.text-button {
  border: none;
  background: transparent;
  color: var(--primary);
  cursor: pointer;
  font-weight: 700;
}

.todo-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 0.85rem;
  overflow: auto;
  max-height: 260px;
}

.todo-item {
  display: grid;
  grid-template-columns: auto 1fr auto;
  gap: 1rem;
  align-items: center;
  padding: 1rem 1.25rem;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 18px;
}

.todo-item.completed {
  opacity: 0.72;
}

.todo-item label {
  display: flex;
  align-items: center;
  gap: 0.85rem;
  width: 100%;
}

.todo-item input[type="checkbox"] {
  width: 1.05rem;
  height: 1.05rem;
  accent-color: var(--primary);
}

.todo-item span {
  word-break: break-word;
}

.todo-item span.completed-text {
  text-decoration: line-through;
  color: var(--text);
}

.todo-item button {
  border: none;
  background: transparent;
  color: var(--danger);
  cursor: pointer;
  padding: 0.25rem;
}

@media (max-width: 560px) {
  body {
    padding: 0.75rem;
  }

  .app-shell {
    max-width: 100%;
  }

  .todo-panel {
    max-width: 100%;
    padding: 1.25rem;
    border-radius: 20px;
  }

  .todo-header h1 {
    font-size: 1.75rem;
    margin: 0 0 0.15rem;
  }

  .todo-header p {
    font-size: 0.9rem;
  }

  .todo-form {
    gap: 0.5rem;
    margin: 1.25rem 0 0.75rem;
  }

  .todo-form input {
    padding: 0.85rem 1rem;
    font-size: 1rem;
  }

  .todo-form button {
    padding: 0.85rem 1.25rem;
    font-size: 0.95rem;
    min-height: 44px;
  }

  .status-pill {
    font-size: 0.9rem;
    padding: 0.65rem 0.9rem;
  }

  .text-button {
    font-size: 0.9rem;
    padding: 0.5rem;
  }

  .todo-list {
    max-height: 400px;
    gap: 0.75rem;
  }

  .todo-item {
    grid-template-columns: auto 1fr;
    padding: 0.9rem 1rem;
    font-size: 0.95rem;
  }

  .todo-item input[type="checkbox"] {
    width: 1.1rem;
    height: 1.1rem;
    min-height: 44px;
  }

  .todo-item button {
    grid-column: 2 / -1;
    justify-self: end;
    padding: 0.5rem;
    min-height: 44px;
  }

  .fab {
    right: 0.75rem;
    bottom: 0.75rem;
    padding: 0.85rem 1rem;
    font-size: 0.95rem;
    min-height: 44px;
    min-width: 44px;
  }

  .todo-popup {
    right: 0.5rem;
    bottom: 0.5rem;
    width: calc(100vw - 1rem);
    max-width: none;
    max-height: 80vh;
    padding: 1rem;
    border-radius: 16px;
  }

  .popup-header h1 {
    font-size: 1.3rem;
  }

  .popup-header p {
    font-size: 0.9rem;
  }

  .icon-button {
    width: 2.4rem;
    height: 2.4rem;
    font-size: 1.1rem;
    min-height: 44px;
    min-width: 44px;
  }

  .settings-panel {
    gap: 0.8rem;
    padding: 0.9rem;
  }

  .slider-row label {
    font-size: 0.9rem;
  }

  .slider-row input[type="range"],
  .slider-row input[type="color"] {
    height: 2.2rem;
    min-height: 44px;
  }
}

.todo-header h1 {
  margin: 0 0 0.25rem;
  font-size: clamp(2rem, 3vw, 2.75rem);
}

.todo-header p {
  margin: 0;
  color: var(--text);
  max-width: 34rem;
}

.todo-form {
  display: flex;
  gap: 0.75rem;
  margin: 1.75rem 0 1rem;
}

.todo-form input {
  flex: 1;
  border: 1px solid var(--border);
  border-radius: 999px;
  padding: 1rem 1.25rem;
  background: var(--surface);
  color: var(--text);
  font-size: 1rem;
}

.todo-form button {
  border: none;
  border-radius: 999px;
  padding: 1rem 1.5rem;
  background: var(--primary);
  color: #030712;
  font-weight: 700;
  cursor: pointer;
  transition: transform 0.2s ease, background 0.2s ease;
}

.todo-form button:hover {
  transform: translateY(-1px);
}

.todo-controls {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 1rem;
  margin-bottom: 1rem;
  flex-wrap: wrap;
}

.status-pill {
  padding: 0.75rem 1rem;
  border-radius: 999px;
  background: rgba(148, 163, 184, 0.12);
  color: var(--text);
  font-size: 0.95rem;
}

.text-button {
  border: none;
  background: transparent;
  color: var(--primary);
  cursor: pointer;
  font-weight: 700;
}

.todo-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 0.85rem;
}

.todo-item {
  display: grid;
  grid-template-columns: auto 1fr auto;
  gap: 1rem;
  align-items: center;
  padding: 1rem 1.25rem;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 18px;
}

.todo-item.completed {
  opacity: 0.72;
}

.todo-item label {
  display: flex;
  align-items: center;
  gap: 0.85rem;
  width: 100%;
}

.todo-item input[type="checkbox"] {
  width: 1.05rem;
  height: 1.05rem;
  accent-color: var(--primary);
}

.todo-item span {
  word-break: break-word;
}

.todo-item span.completed-text {
  text-decoration: line-through;
  color: var(--text);
}

.todo-item button {
  border: none;
  background: transparent;
  color: var(--danger);
  cursor: pointer;
  padding: 0.25rem;
}