.practice { display: grid; grid-template-columns: 320px minmax(0, 1fr); gap: 48px; padding-top: 48px; padding-bottom: 80px; align-items: start; }
@media (max-width: 900px) { .practice { grid-template-columns: 1fr; } }
.nav-links a[aria-current="page"] { color: var(--fg); }
.brief h1 { font-size: 38px; font-weight: 700; }
.brief p { margin-top: 14px; color: var(--muted); }
.tasks { list-style: none; padding: 0; margin: 26px 0 0; display: grid; gap: 10px; }
.tasks li { display: flex; align-items: center; gap: 12px; padding: 14px 16px; border-radius: 14px; background: var(--surface); border: 1px solid var(--line); transition: border-color 0.3s, background 0.3s; }
.tick { position: relative; width: 22px; height: 22px; border-radius: 50%; border: 2px solid var(--line); flex: none; transition: background 0.3s, border-color 0.3s; }
.tasks li.done { border-color: color-mix(in srgb, #16a34a 45%, var(--line)); }
.tasks li.done .tick { background: #16a34a; border-color: #16a34a; }
.tasks li.done .tick::after { content: ""; position: absolute; left: 6px; top: 2px; width: 5px; height: 10px; border: solid #fff; border-width: 0 2px 2px 0; transform: rotate(45deg); }

.app { border-radius: 18px; background: var(--surface); border: 1px solid var(--line); box-shadow: var(--shadow); padding: 26px; display: grid; gap: 22px; }
.app-top { display: flex; align-items: center; justify-content: space-between; }
.app-title { font-size: 22px; font-weight: 650; }
.app-row { display: flex; gap: 28px; flex-wrap: wrap; }
.toggle { display: inline-flex; align-items: center; gap: 10px; cursor: pointer; font-weight: 500; position: relative; }
.toggle input { position: absolute; opacity: 0; width: 1px; height: 1px; }
.toggle span { width: 44px; height: 26px; border-radius: 999px; background: var(--line); position: relative; transition: background 0.2s; }
.toggle span::after { content: ""; position: absolute; top: 3px; left: 3px; width: 20px; height: 20px; border-radius: 50%; background: #fff; box-shadow: 0 1px 2px rgb(0 0 0 / 0.25); transition: transform 0.25s var(--ease); }
.toggle input:checked + span { background: var(--accent); }
.toggle input:checked + span::after { transform: translateX(18px); }
.toggle input:focus-visible + span { outline: 2px solid var(--accent); outline-offset: 2px; }

.board { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 14px; }
@media (max-width: 640px) { .board { grid-template-columns: 1fr; } }
.col { min-height: 220px; padding: 14px; border-radius: 14px; background: var(--bg); border: 1.5px dashed transparent; display: grid; gap: 10px; align-content: start; transition: border-color 0.2s, background 0.2s; }
.col.hot { border-color: var(--accent); background: var(--accent-soft); }
.col h2 { font-size: 13px; font-weight: 600; color: var(--muted); }
.card { padding: 14px; border-radius: 12px; background: var(--surface); border: 1px solid var(--line); box-shadow: 0 6px 14px -10px rgb(15 23 42 / 0.4); cursor: grab; user-select: none; touch-action: none; font-weight: 500; }
.card.dragging { cursor: grabbing; box-shadow: 0 20px 40px -16px rgb(15 23 42 / 0.5); position: relative; z-index: 2; }
.card.new { animation: rise 0.6s var(--ease) both; }
.done-msg { grid-column: 1 / -1; padding: 16px 18px; border-radius: 14px; background: color-mix(in srgb, #16a34a 14%, var(--surface)); font-weight: 600; }