:root {
    --bg: #0d1117;
    --col-bg: #161b22;
    --card-bg: #21262d;
    --text: #c9d1d9;
    --border: #30363d;
    --accent: #58a6ff;
    --danger: #f85149;
    --success: #3fb950;
    --warning: #d29922;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Helvetica, Arial, sans-serif;
    background-color: var(--bg);
    color: var(--text);
    margin: 0;
    padding: 20px;
    display: flex;
    flex-direction: column;
    align-items: center;
}

.header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    width: 100%;
    max-width: 960px;
    margin-bottom: 30px;
}

h1 { font-size: 1.5rem; font-weight: 600; margin: 0; }

.board {
    display: flex;
    gap: 20px;
    align-items: flex-start;
    width: 100%;
    justify-content: center;
    flex-wrap: wrap;
}

.column {
    background-color: var(--col-bg);
    width: 300px;
    border-radius: 8px;
    border: 1px solid var(--border);
    padding: 12px;
    display: flex;
    flex-direction: column;
    transition: 0.2s;
}

.column.drag-over { border-color: var(--accent); background: #1c2128; }

.column h2 {
    font-size: 0.85rem;
    text-transform: uppercase;
    margin: 0 0 15px 5px;
    font-weight: 600;
}

[data-status="todo"] h2 { color: var(--accent); }
[data-status="inprogress"] h2 { color: var(--warning); }
[data-status="done"] h2 { color: var(--success); }

.tasks { min-height: 20px; }

.task {
    background: var(--card-bg);
    border: 1px solid var(--border);
    padding: 12px;
    border-radius: 6px;
    margin-bottom: 10px;
    cursor: grab;
    font-size: 0.9rem;
    transition: 0.1s;
}

.task:hover { border-color: #8b949e; }
.task.dragging { opacity: 0.4; transform: scale(0.95); }

button { cursor: pointer; border-radius: 6px; font-weight: 500; transition: 0.2s; }

.add-btn {
    width: 100%;
    background: transparent;
    border: 1px dashed var(--border);
    color: #8b949e;
    padding: 8px;
    margin-top: 5px;
}

.add-btn:hover { color: var(--accent); border-color: var(--accent); background: #1f242c; }

.danger-btn {
    background: transparent;
    border: 1px solid var(--border);
    color: var(--danger);
    padding: 6px 12px;
    font-size: 0.8rem;
}

.danger-btn:hover { background: var(--danger); color: white; border-color: var(--danger); }