:root {
    --primary-color: #4ECDC4;
    --secondary-color: #FF6B6B;
    --background-color: #f5f5f5;
    --text-color: #333;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, sans-serif;
    background-color: var(--background-color);
    color: var(--text-color);
    line-height: 1.6;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 2rem;
    text-align: center;
}

h1 {
    font-size: 3rem;
    margin-bottom: 1rem;
    color: var(--primary-color);
}

.auth-buttons {
    margin-top: 2rem;
}

.btn {
    display: inline-block;
    padding: 0.75rem 1.5rem;
    margin: 0.5rem;
    text-decoration: none;
    border-radius: 5px;
    font-weight: 500;
    transition: background-color 0.3s;
}

.btn-primary {
    background-color: var(--primary-color);
    color: white;
}

.btn-primary:hover {
    background-color: #3dbdb5;
}

.btn-secondary {
    background-color: var(--secondary-color);
    color: white;
}

.btn-secondary:hover {
    background-color: #e55a5a;
}

.oauth-buttons {
    margin-top: 2rem;
}

.btn-oauth {
    display: block;
    width: 100%;
    max-width: 300px;
    margin: 0.5rem auto;
    padding: 0.75rem 1.5rem;
    text-align: center;
}

.btn-herald {
    background-color: #6366f1;
    color: white;
}

.btn-herald:hover {
    background-color: #4f46e5;
}

.btn-scout {
    background-color: #10b981;
    color: white;
}

.btn-scout:hover {
    background-color: #059669;
}

.divider {
    margin: 2rem 0;
    text-align: center;
    position: relative;
}

.divider::before,
.divider::after {
    content: '';
    position: absolute;
    top: 50%;
    width: 45%;
    height: 1px;
    background-color: #ddd;
}

.divider::before {
    left: 0;
}

.divider::after {
    right: 0;
}

.divider span {
    background-color: var(--background-color);
    padding: 0 1rem;
    color: #666;
}

.login-form {
    max-width: 300px;
    margin: 0 auto;
}

.form-group {
    margin-bottom: 1rem;
    text-align: left;
}

.form-group label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 500;
}

.form-group input {
    width: 100%;
    padding: 0.75rem;
    border: 1px solid #ddd;
    border-radius: 5px;
    font-size: 1rem;
}

.register-link {
    margin-top: 1.5rem;
    color: #666;
}

.register-link a {
    color: var(--primary-color);
    text-decoration: none;
}

.register-link a:hover {
    text-decoration: underline;
}

.main-nav {
    display: flex;
    justify-content: space-around;
    background: white;
    padding: 0.75rem 1rem;
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
    position: sticky;
    top: 0;
    z-index: 100;
}

.nav-item {
    display: flex;
    flex-direction: column;
    align-items: center;
    text-decoration: none;
    color: #666;
    padding: 0.5rem 1rem;
    border-radius: 8px;
    transition: all 0.2s;
}

.nav-item:hover {
    background-color: #f0f0f0;
    color: var(--primary-color);
}

.nav-item.active {
    color: var(--primary-color);
    background-color: rgba(78, 205, 196, 0.1);
}

.nav-icon {
    font-size: 1.5rem;
    margin-bottom: 0.25rem;
}

.nav-label {
    font-size: 0.75rem;
    font-weight: 500;
}

.nav-dropdown {
    position: relative;
}

.nav-dropdown-menu {
    display: none;
    position: absolute;
    top: 100%;
    right: 0;
    background: white;
    border-radius: 8px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.15);
    min-width: 150px;
    padding: 0.5rem 0;
    z-index: 200;
}

.nav-dropdown:hover .nav-dropdown-menu {
    display: block;
}

.nav-dropdown-menu a {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.5rem 1rem;
    text-decoration: none;
    color: #666;
    font-size: 0.85rem;
    white-space: nowrap;
}

.nav-dropdown-menu a:hover {
    background-color: #f0f0f0;
    color: var(--primary-color);
}

.main-content {
    max-width: 1200px;
    margin: 0 auto;
    padding: 2rem;
}

.quick-actions {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
    gap: 1rem;
    margin-top: 2rem;
}

.quick-action-btn {
    display: flex;
    flex-direction: column;
    align-items: center;
    padding: 1.5rem;
    background: white;
    border-radius: 10px;
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
    text-decoration: none;
    color: var(--text-color);
    transition: transform 0.2s, box-shadow 0.2s;
}

.quick-action-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 8px rgba(0,0,0,0.15);
}

.quick-action-icon {
    font-size: 2rem;
    margin-bottom: 0.5rem;
}

.tabs {
    display: flex;
    gap: 0.5rem;
    margin-bottom: 1.5rem;
    background: white;
    padding: 0.5rem;
    border-radius: 10px;
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
}

.tab {
    flex: 1;
    padding: 0.75rem;
    border: none;
    background: transparent;
    border-radius: 8px;
    cursor: pointer;
    font-weight: 500;
    color: #666;
    transition: all 0.2s;
}

.tab:hover {
    background: #f0f0f0;
}

.tab.active {
    background: var(--primary-color);
    color: white;
}

.modal {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0,0,0,0.5);
    display: flex;
    justify-content: center;
    align-items: center;
    z-index: 1000;
}

.modal-content {
    background: white;
    padding: 2rem;
    border-radius: 15px;
    width: 90%;
    max-width: 400px;
    box-shadow: 0 10px 40px rgba(0,0,0,0.2);
}

.modal-content h2 {
    margin-bottom: 1.5rem;
    color: var(--text-color);
}

.modal-actions {
    display: flex;
    gap: 1rem;
    margin-top: 1.5rem;
}

.modal-actions .btn {
    flex: 1;
}

.radio-group {
    display: flex;
    gap: 1rem;
}

.radio-label {
    flex: 1;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 1rem;
    background: #f5f5f5;
    border-radius: 10px;
    cursor: pointer;
    transition: all 0.2s;
}

.radio-label:has(input:checked) {
    background: rgba(78, 205, 196, 0.15);
    border: 2px solid var(--primary-color);
}

.radio-label input {
    display: none;
}

.transaction-right {
    display: flex;
    flex-direction: column;
    align-items: flex-end;
    gap: 0.5rem;
}

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

.btn-small {
    padding: 0.4rem 0.8rem;
    border: 1px solid #ddd;
    background: white;
    border-radius: 5px;
    font-size: 0.8rem;
    cursor: pointer;
    transition: all 0.2s;
}

.btn-small:hover {
    background: #f0f0f0;
}

.transaction-tag {
    font-size: 0.75rem;
    padding: 0.25rem 0.5rem;
    border-radius: 10px;
}

.transaction-tag.settled {
    background: #d4edda;
    color: #155724;
}

.debt-item-link {
    text-decoration: none;
    color: inherit;
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem;
    border-bottom: 1px solid #eee;
    transition: background 0.2s;
}

.debt-item-link:hover {
    background: #f9f9f9;
}

.person-header {
    margin-bottom: 1.5rem;
}

.back-link {
    color: var(--primary-color);
    text-decoration: none;
    font-size: 0.9rem;
    display: inline-block;
    margin-bottom: 0.5rem;
}

.back-link:hover {
    text-decoration: underline;
}

.person-direction {
    color: #666;
    margin-top: 0.25rem;
}

.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 1rem;
    margin-bottom: 2rem;
}

.stat-card {
    background: white;
    padding: 1.5rem;
    border-radius: 10px;
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
    text-align: center;
    transition: box-shadow 0.2s, transform 0.2s;
}

.stat-card[onclick]:hover {
    box-shadow: 0 4px 12px rgba(0,0,0,0.15);
    transform: translateY(-2px);
}

.stat-card h3 {
    color: #666;
    font-size: 0.9rem;
    margin-bottom: 0.5rem;
}

.stat-value {
    font-size: 2rem;
    font-weight: bold;
    color: var(--primary-color);
}

.stat-card.income .stat-value {
    color: #27AE60;
}

.stat-card.expense .stat-value {
    color: #E74C3C;
}

.income-amount {
    color: #27AE60;
    font-weight: bold;
}

.expense-amount {
    color: #E74C3C;
    font-weight: bold;
}

.transactions-list {
    background: white;
    border-radius: 10px;
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
}

.transaction-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem;
    border-bottom: 1px solid #eee;
}

.transaction-item:last-child {
    border-bottom: none;
}

.transaction-info {
    display: flex;
    flex-direction: column;
}

.transaction-desc {
    font-weight: 500;
}

.transaction-date {
    font-size: 0.85rem;
    color: #666;
}

.transaction-amount {
    font-weight: bold;
    color: var(--secondary-color);
}

.loading, .empty {
    padding: 2rem;
    text-align: center;
    color: #666;
}

.form {
    max-width: 500px;
    background: white;
    padding: 2rem;
    border-radius: 10px;
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
}

.form-group {
    margin-bottom: 1.5rem;
}

.form-group label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 500;
}

.form-group input,
.form-group select,
.form-group textarea {
    width: 100%;
    padding: 0.75rem;
    border: 1px solid #ddd;
    border-radius: 5px;
    font-size: 1rem;
}

.form-group textarea {
    resize: vertical;
}

.source-row {
    display: flex;
    gap: 0.5rem;
    align-items: center;
}

.source-row select {
    flex: 1;
}

.btn-link {
    display: inline-block;
    padding: 0.75rem 1rem;
    background: var(--primary-color);
    color: white;
    text-decoration: none;
    border-radius: 5px;
    font-size: 0.9rem;
    white-space: nowrap;
}

.btn-link:hover {
    background: #3dbdb5;
}