:root {
    --color-bg: #f4f4f9;
    --color-sidebar-bg: #ffffff;
    --color-sidebar-text: #333;
    --color-sidebar-active: #1abc9c;
    --color-card-bg: #ffffff;
    --color-text: #333;
    --color-green: #27ae60;
    --color-red: #e74c3c;
    --color-border: #ddd;
    --border-radius: 10px;
    --transition: 0.25s ease;
    --font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    --shadow: 0 4px 12px rgba(0,0,0,0.08);
}

body {
    margin: 0;
    font-family: var(--font-family);
    background-color: var(--color-bg);
    color: var(--color-text);
}

h2 {
    margin-top: 0;
    font-weight: 600;
}

button {
    cursor: pointer;
    border: none;
    border-radius: var(--border-radius);
    padding: 4px 10px;
    font-size: 0.85rem;
    transition: var(--transition);
    background-color: #f0f0f0;
}

button:hover {
    background-color: #e0e0e0;
}

.container {
    display: flex;
    min-height: 100vh;
}

.sidebar {
    width: 180px;
    height: 100vh;
    background-color: var(--color-sidebar-bg);
    color: var(--color-sidebar-text);
    padding: 20px;
    box-sizing: border-box;
    font-weight: 500;
    position: sticky;
    top: 0;
    align-self: flex-start;
    border-right: 1px solid #ddd;
}

.sidebar h2 {
    font-size: 22px;
    margin-bottom: 20px;
}

.sidebar ul {
    list-style: none;
    padding: 0;
    margin: 0;
}

.sidebar ul li {
    margin-bottom: 12px;
}

.sidebar a {
    color: var(--color-sidebar-text);
    text-decoration: none;
    display: block;
    padding: 4px 0;
    transition: var(--transition);
    font-weight: 500;
    border-left: 3px solid transparent;
}

.sidebar a.active {
    padding-left: 1px;
}

.content {
    flex: 1;
    padding: 20px 30px;
    box-sizing: border-box;
}

.card {
    background-color: var(--color-card-bg);
    padding: 20px;
    margin-bottom: 20px;
    border-radius: var(--border-radius);
    box-shadow: var(--shadow);
    transition: transform 0.25s ease;
}

.card:hover {
    transform: translateY(-2px);
}

.overview-cards {
    display: flex;
    gap: 20px;
    flex-wrap: wrap;
}

.overview-cards .card {
    flex: 1;
    text-align: center;
    padding: 25px 20px;
}

.overview-cards .card p {
    font-size: 1.1rem;
    margin: 0;
    opacity: 0.7;
}

.overview-cards .card h3 {
    font-size: 2.5rem;
    margin: 10px 0 0 0;
    font-weight: 700;
}

ul {
    list-style: none;
    padding: 0;
    margin: 0;
}

li {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 10px 12px;
    margin-bottom: 8px;
    border-radius: var(--border-radius);
    background-color: #fff;
    transition: var(--transition);
}

li:hover {
    box-shadow: var(--shadow);
}

li.transaction-item.income {
    background-color: #eafaf1;
}

li.transaction-item.income span {
    color: var(--color-green);
}

li.done {
    background-color: #fff;
}

li.done .task-title {
    text-decoration: line-through;
    color: #999;
}

li.habit-item.done span.title::after {
    content: ' ✔';
    color: var(--color-green);
    font-weight: bold;
    margin-left: 5px;
}

li.transaction-item.expense {
    background-color: #fdeaea;
}

li.transaction-item.expense span {
    color: var(--color-red);
}

li .task-text, li .habit-text {
    flex: 1;
    text-align: right;
    margin-right: 10px;
}

li div {
    display: flex;
    gap: 8px;
    margin-left: auto;
}

li div button {
    padding: 4px 10px;
    font-size: 0.85rem;
}

.empty {
    text-align: center;
    color: #999;
    font-style: italic;
}

input, select, button {
    display: inline-block;
    vertical-align: middle;
    margin-bottom: 6px;
}

#todo input, #habits input, #budget input, #budget select {
    padding: 8px;
    border: 1px solid var(--color-border);
    border-radius: var(--border-radius);
    font-size: 0.9rem;
}

#todo button, #habits button, #budget button {
    padding: 8px 14px;
    border-radius: var(--border-radius);
    background-color: #f9f9f9;
    border: 1px solid var(--color-border);
    transition: var(--transition);
}

#todo button:hover, #habits button:hover, #budget button:hover {
    background-color: #f0f0f0;
}

#timer-display {
    font-size: 52px;
    text-align: left;
    margin-bottom: 12px;
    font-weight: 700;
}

#timer-container {
    display: flex;
    flex-direction: column;
    align-items: center;
}

#timer-controls button {
  padding: 8px 14px;
  border-radius: var(--border-radius);
  background-color: #f9f9f9;
  border: 1px solid var(--color-border);
  font-size: 0.85rem;
  transition: var(--transition);
}

#timer-controls button:hover {
  background-color: #f0f0f0;
}