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

:root {
    --primary-color: #2563eb;
    --primary-hover: #1d4ed8;
    --danger-color: #dc2626;
    --danger-hover: #b91c1c;
    --success-color: #16a34a;
    --text-color: #1f2937;
    --text-muted: #6b7280;
    --bg-color: #f9fafb;
    --card-bg: #ffffff;
    --border-color: #e5e7eb;
    --highlight-color: #0066cc;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    background-color: var(--bg-color);
    color: var(--text-color);
    line-height: 1.5;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

/* Header */
header {
    background-color: var(--card-bg);
    border-bottom: 1px solid var(--border-color);
    padding: 0 1rem;
}

nav {
    max-width: 1200px;
    margin: 0 auto;
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 1rem 0;
}

nav h1 {
    font-size: 1.5rem;
    color: var(--primary-color);
}

nav ul {
    list-style: none;
    display: flex;
    gap: 1.5rem;
}

nav a {
    color: var(--text-muted);
    text-decoration: none;
    font-weight: 500;
    padding: 0.5rem 1rem;
    border-radius: 0.375rem;
    transition: all 0.2s;
}

nav a:hover {
    color: var(--text-color);
    background-color: var(--bg-color);
}

nav a.active {
    color: var(--primary-color);
    background-color: #eff6ff;
}

/* Main Content */
main {
    flex: 1;
    padding: 1.5rem;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
}

/* Sections */
section {
    background-color: var(--card-bg);
    border-radius: 0.5rem;
    border: 1px solid var(--border-color);
    padding: 1.5rem;
    margin-bottom: 1.5rem;
}

section h2 {
    font-size: 1.125rem;
    margin-bottom: 1rem;
    color: var(--text-color);
}

/* Filters */
.filters .filter-row {
    display: flex;
    flex-wrap: wrap;
    gap: 1rem;
    align-items: flex-end;
}

.filter-group {
    display: flex;
    flex-direction: column;
    gap: 0.375rem;
}

.filter-group label {
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--text-muted);
}

.filter-group.checkbox-group {
    flex-direction: row;
    align-items: center;
}

.filter-group.checkbox-group label {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    cursor: pointer;
}

/* Form Elements */
select, input[type="text"], input[type="number"], input[type="date"] {
    padding: 0.5rem 0.75rem;
    border: 1px solid var(--border-color);
    border-radius: 0.375rem;
    font-size: 0.875rem;
    background-color: var(--card-bg);
    min-width: 200px;
}

select:focus, input:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.1);
}

input[type="checkbox"] {
    width: 1rem;
    height: 1rem;
    cursor: pointer;
}

/* Buttons */
.btn {
    padding: 0.5rem 1rem;
    border: none;
    border-radius: 0.375rem;
    font-size: 0.875rem;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.2s;
}

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

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

.btn-secondary {
    background-color: var(--bg-color);
    color: var(--text-color);
    border: 1px solid var(--border-color);
}

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

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

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

.btn-sm {
    padding: 0.25rem 0.5rem;
    font-size: 0.75rem;
}

/* Table */
.table-container {
    overflow-x: auto;
}

table {
    width: 100%;
    border-collapse: collapse;
}

th, td {
    padding: 0.75rem 1rem;
    text-align: left;
    border-bottom: 1px solid var(--border-color);
}

th {
    background-color: var(--bg-color);
    font-weight: 600;
    font-size: 0.875rem;
    color: var(--text-muted);
}

th.sortable {
    cursor: pointer;
    user-select: none;
}

th.sortable:hover {
    background-color: var(--border-color);
}

th.sortable::after {
    content: '';
    margin-left: 0.5rem;
}

th.sort-asc::after {
    content: ' \2191';
}

th.sort-desc::after {
    content: ' \2193';
}

tbody tr:hover {
    background-color: var(--bg-color);
}

tr.never-sung td:first-child,
tr.never-sung td:nth-child(2) {
    color: var(--highlight-color);
}

.count-badge {
    font-size: 0.875rem;
    font-weight: normal;
    color: var(--text-muted);
}

/* History Page */
.add-entry .entry-form {
    display: flex;
    flex-wrap: wrap;
    gap: 1.5rem;
    align-items: flex-end;
}

.date-nav {
    display: flex;
    align-items: center;
    gap: 0.25rem;
}

.date-nav input {
    min-width: 150px;
}

.hint {
    font-size: 0.875rem;
    color: var(--text-muted);
    margin-bottom: 1rem;
}

.feedback {
    font-size: 0.875rem;
    padding: 0.5rem 1rem;
    border-radius: 0.375rem;
}

.feedback.success {
    background-color: #dcfce7;
    color: var(--success-color);
}

.feedback.error {
    background-color: #fee2e2;
    color: var(--danger-color);
}

.history-section h2 {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.history-actions {
    margin-bottom: 1rem;
}

.date-section {
    margin-bottom: 1.5rem;
}

.date-header {
    font-size: 1rem;
    color: var(--text-muted);
    padding-bottom: 0.5rem;
    border-bottom: 1px solid var(--border-color);
    margin-bottom: 0.5rem;
}

.hymn-list {
    list-style: none;
}

.hymn-list li {
    display: flex;
    align-items: center;
    padding: 0.5rem 0;
    gap: 1rem;
}

.hymn-list li:not(:last-child) {
    border-bottom: 1px solid var(--bg-color);
}

.hymn-number {
    font-weight: 600;
    min-width: 50px;
}

.hymn-title {
    flex: 1;
}

.empty-message {
    color: var(--text-muted);
    text-align: center;
    padding: 2rem;
}

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

.modal.hidden {
    display: none;
}

.modal-content {
    background-color: var(--card-bg);
    padding: 1.5rem;
    border-radius: 0.5rem;
    max-width: 400px;
    width: 90%;
}

.modal-content h3 {
    margin-bottom: 1rem;
}

.modal-content p {
    margin-bottom: 1rem;
    color: var(--text-muted);
}

.modal-content .form-group {
    margin-bottom: 1rem;
}

.modal-content .form-group label {
    display: block;
    margin-bottom: 0.375rem;
    font-weight: 500;
}

.modal-actions {
    display: flex;
    justify-content: flex-end;
    gap: 0.75rem;
}

/* Footer */
footer {
    background-color: var(--card-bg);
    border-top: 1px solid var(--border-color);
    padding: 1rem;
    text-align: center;
    color: var(--text-muted);
    font-size: 0.875rem;
}

/* Responsive */
@media (max-width: 768px) {
    nav {
        flex-direction: column;
        gap: 1rem;
    }

    .filters .filter-row {
        flex-direction: column;
    }

    select, input[type="text"], input[type="number"] {
        width: 100%;
        min-width: auto;
    }

    th, td {
        padding: 0.5rem;
        font-size: 0.875rem;
    }

    .add-entry .entry-form {
        flex-direction: column;
        align-items: stretch;
    }

    .hymn-list li {
        flex-wrap: wrap;
    }
}