:root {
  --rh-red: #ee0000;
  --rh-dark: #151515;
  --rh-blue: #2f6cbf;
  --rh-slate: #4f5255;
  --rh-light: #f6f7f8;
  --rh-border: #d9dde0;
  --rh-success: #2e7d32;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: Arial, Helvetica, sans-serif;
  background: linear-gradient(135deg, #fff5f5 0%, var(--rh-light) 50%, #eff4ff 100%);
  color: var(--rh-dark);
  min-height: 100vh;
}

button,
input {
  font: inherit;
}

.app-shell {
  max-width: 960px;
  margin: 0 auto;
  padding: 2rem 1rem 3rem;
}

.hero {
  background: linear-gradient(90deg, var(--rh-dark) 0%, #2b2b2b 100%);
  color: white;
  padding: 2rem;
  border-radius: 24px;
  box-shadow: 0 20px 45px rgba(0, 0, 0, 0.14);
  margin-bottom: 1.5rem;
}

.brand {
  display: flex;
  align-items: center;
  gap: 1rem;
  margin-bottom: 0.8rem;
}

.brand-badge {
  display: inline-grid;
  place-items: center;
  width: 54px;
  height: 54px;
  border-radius: 14px;
  background: var(--rh-red);
  font-weight: 700;
  letter-spacing: 0.08em;
}

.eyebrow {
  margin: 0 0 0.2rem;
  color: #ffd2d2;
  text-transform: uppercase;
  font-size: 0.8rem;
  letter-spacing: 0.15em;
}

.hero h1 {
  margin: 0;
  font-size: clamp(1.8rem, 2.2vw, 2.4rem);
}

.hero-copy {
  margin: 0;
  max-width: 720px;
  line-height: 1.6;
  color: #f0f0f0;
}

.card {
  background: white;
  border: 1px solid var(--rh-border);
  border-radius: 24px;
  box-shadow: 0 18px 40px rgba(21, 21, 21, 0.08);
  padding: 1.25rem;
}

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

.todo-form input {
  flex: 1;
  padding: 0.9rem 1rem;
  border: 1px solid var(--rh-border);
  border-radius: 999px;
  outline: none;
}

.todo-form input:focus {
  border-color: var(--rh-blue);
  box-shadow: 0 0 0 3px rgba(47, 108, 191, 0.16);
}

.todo-form button,
.filter,
.action-btn {
  border: none;
  border-radius: 999px;
  cursor: pointer;
  transition: transform 140ms ease, box-shadow 140ms ease;
}

.todo-form button {
  background: var(--rh-red);
  color: white;
  padding: 0.9rem 1.2rem;
  font-weight: 700;
}

.todo-form button:hover,
.filter:hover,
.action-btn:hover {
  transform: translateY(-1px);
  box-shadow: 0 8px 20px rgba(0, 0, 0, 0.12);
}

.toolbar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 1rem;
  flex-wrap: wrap;
  margin-bottom: 1rem;
  color: var(--rh-slate);
}

.filters {
  display: flex;
  gap: 0.5rem;
}

.filter {
  padding: 0.6rem 0.9rem;
  background: var(--rh-light);
  color: var(--rh-dark);
}

.filter.active {
  background: var(--rh-blue);
  color: white;
}

.todo-list {
  list-style: none;
  padding: 0;
  margin: 0;
  display: grid;
  gap: 0.75rem;
}

.todo-item {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.75rem;
  padding: 0.9rem 1rem;
  border: 1px solid var(--rh-border);
  border-radius: 16px;
  background: #fff;
}

.todo-item.completed .todo-text {
  text-decoration: line-through;
  color: #7c8185;
}

.todo-content {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  flex: 1;
}

.checkbox {
  width: 20px;
  height: 20px;
  accent-color: var(--rh-red);
  cursor: pointer;
}

.todo-text {
  font-weight: 600;
}

.actions {
  display: flex;
  gap: 0.5rem;
}

.action-btn {
  padding: 0.45rem 0.65rem;
  background: var(--rh-light);
  color: var(--rh-dark);
}

.empty-state {
  text-align: center;
  padding: 2rem 1rem;
  color: var(--rh-slate);
  border: 1px dashed var(--rh-border);
  border-radius: 16px;
  background: var(--rh-light);
}

@media (max-width: 640px) {
  .todo-form {
    flex-direction: column;
  }

  .toolbar {
    align-items: flex-start;
  }

  .filters {
    width: 100%;
    flex-wrap: wrap;
  }
}