/* ===== CSS Custom Properties ===== */
:root {
  --clr-bg: #0f1117;
  --clr-surface: #1a1d27;
  --clr-surface-hover: #222632;
  --clr-border: #2a2e3b;
  --clr-text: #e4e6ed;
  --clr-text-muted: #8b8fa3;
  --clr-primary: #6c5ce7;
  --clr-primary-light: #a29bfe;
  --clr-success: #00cec9;
  --clr-danger: #ff6b6b;
  --clr-health: #fd79a8;
  --clr-productivity: #fdcb6e;
  --clr-learning: #74b9ff;
  --clr-personal: #a29bfe;
  --radius: 12px;
  --radius-sm: 8px;
  --shadow: 0 2px 12px rgba(0,0,0,.25);
  --font: 'Inter', system-ui, sans-serif;
  --transition: .2s ease;
}

/* ===== Reset ===== */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
body {
  font-family: var(--font);
  background: var(--clr-bg);
  color: var(--clr-text);
  min-height: 100vh;
  display: flex;
  justify-content: center;
  padding: 2rem 1rem;
}

/* ===== App Container ===== */
.app {
  width: 100%;
  max-width: 640px;
}

/* ===== Header ===== */
.header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 2rem;
}
.header__title {
  font-size: 1.75rem;
  font-weight: 700;
}
.header__subtitle {
  color: var(--clr-text-muted);
  font-size: .875rem;
  margin-top: .25rem;
}

/* Progress Ring */
.progress-ring {
  position: relative;
  width: 60px;
  height: 60px;
}
.progress-ring svg { width: 100%; height: 100%; transform: rotate(-90deg); }
.progress-ring__bg {
  fill: none;
  stroke: var(--clr-border);
  stroke-width: 5;
}
.progress-ring__fill {
  fill: none;
  stroke: var(--clr-success);
  stroke-width: 5;
  stroke-linecap: round;
  stroke-dasharray: 163.36;
  stroke-dashoffset: 163.36;
  transition: stroke-dashoffset .6s ease;
}
.progress-ring__text {
  position: absolute;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: .75rem;
  font-weight: 600;
  color: var(--clr-success);
}

/* ===== Add Habit ===== */
.add-habit {
  background: var(--clr-surface);
  border: 1px solid var(--clr-border);
  border-radius: var(--radius);
  padding: 1.25rem;
  margin-bottom: 1.5rem;
}
.add-habit__input-group {
  display: flex;
  gap: .75rem;
  margin-bottom: .75rem;
}
.add-habit__input {
  flex: 1;
  padding: .7rem 1rem;
  border: 1px solid var(--clr-border);
  border-radius: var(--radius-sm);
  background: var(--clr-bg);
  color: var(--clr-text);
  font-size: .95rem;
  font-family: var(--font);
  outline: none;
  transition: border var(--transition);
}
.add-habit__input:focus { border-color: var(--clr-primary); }
.add-habit__icon-input {
  width: 52px;
  text-align: center;
  padding: .7rem .5rem;
  border: 1px solid var(--clr-border);
  border-radius: var(--radius-sm);
  background: var(--clr-bg);
  color: var(--clr-text);
  font-size: 1.25rem;
  outline: none;
  transition: border var(--transition);
}
.add-habit__icon-input:focus { border-color: var(--clr-primary); }
.add-habit__row {
  display: flex;
  gap: .75rem;
}
.add-habit__select {
  flex: 1;
  padding: .65rem 1rem;
  border: 1px solid var(--clr-border);
  border-radius: var(--radius-sm);
  background: var(--clr-bg);
  color: var(--clr-text);
  font-size: .875rem;
  font-family: var(--font);
  cursor: pointer;
  outline: none;
}
.add-habit__btn {
  padding: .65rem 1.5rem;
  background: var(--clr-primary);
  color: #fff;
  border: none;
  border-radius: var(--radius-sm);
  font-size: .875rem;
  font-weight: 600;
  font-family: var(--font);
  cursor: pointer;
  transition: background var(--transition);
}
.add-habit__btn:hover { background: var(--clr-primary-light); }

/* ===== Filters ===== */
.filters {
  display: flex;
  gap: .5rem;
  flex-wrap: wrap;
  margin-bottom: 1.25rem;
}
.filters__btn {
  padding: .45rem .9rem;
  border: 1px solid var(--clr-border);
  border-radius: 999px;
  background: transparent;
  color: var(--clr-text-muted);
  font-size: .8rem;
  font-family: var(--font);
  cursor: pointer;
  transition: all var(--transition);
}
.filters__btn:hover { border-color: var(--clr-primary); color: var(--clr-text); }
.filters__btn--active {
  background: var(--clr-primary);
  border-color: var(--clr-primary);
  color: #fff;
}

/* ===== Habit Cards ===== */
.habits__empty {
  text-align: center;
  color: var(--clr-text-muted);
  padding: 3rem 1rem;
  font-size: .95rem;
}

.habit-card {
  display: flex;
  align-items: center;
  gap: 1rem;
  background: var(--clr-surface);
  border: 1px solid var(--clr-border);
  border-radius: var(--radius);
  padding: 1rem 1.25rem;
  margin-bottom: .75rem;
  transition: background var(--transition), border var(--transition);
}
.habit-card:hover { background: var(--clr-surface-hover); }
.habit-card--done { border-left: 3px solid var(--clr-success); }

.habit-card__check {
  width: 28px;
  height: 28px;
  border: 2px solid var(--clr-border);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  flex-shrink: 0;
  transition: all var(--transition);
  font-size: .85rem;
}
.habit-card__check:hover { border-color: var(--clr-success); }
.habit-card__check--done {
  background: var(--clr-success);
  border-color: var(--clr-success);
  color: #fff;
}

.habit-card__info { flex: 1; min-width: 0; }
.habit-card__name {
  font-size: .95rem;
  font-weight: 600;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}
.habit-card__meta {
  display: flex;
  gap: .75rem;
  margin-top: .25rem;
  font-size: .75rem;
  color: var(--clr-text-muted);
}
.habit-card__streak { color: var(--clr-success); font-weight: 500; }

.habit-card__category {
  display: inline-block;
  padding: .15rem .55rem;
  border-radius: 999px;
  font-size: .7rem;
  font-weight: 500;
  flex-shrink: 0;
}
.habit-card__category--health     { background: rgba(253,121,168,.15); color: var(--clr-health); }
.habit-card__category--productivity { background: rgba(253,203,110,.15); color: var(--clr-productivity); }
.habit-card__category--learning   { background: rgba(116,185,255,.15); color: var(--clr-learning); }
.habit-card__category--personal   { background: rgba(162,155,254,.15); color: var(--clr-personal); }

.habit-card__delete {
  background: none;
  border: none;
  color: var(--clr-text-muted);
  font-size: 1.1rem;
  cursor: pointer;
  padding: .25rem;
  opacity: 0;
  transition: opacity var(--transition), color var(--transition);
}
.habit-card:hover .habit-card__delete { opacity: 1; }
.habit-card__delete:hover { color: var(--clr-danger); }

/* ===== Responsive ===== */
@media (max-width: 480px) {
  .header__title { font-size: 1.35rem; }
  .add-habit__row { flex-direction: column; }
  .add-habit__btn { width: 100%; }
  .filters { gap: .35rem; }
  .filters__btn { font-size: .7rem; padding: .35rem .65rem; }
}