:root {
    --background-color: #ffffff;
    --text-color: #212529;
    --header-color: #343a40;
    --input-border-color: #ced4da;
    --input-background-color: #fff;
    --button-border-color: #ced4da;
    --button-background-color: #f8f9fa;
    --button-hover-background-color: #e9ecef;
    --button-active-background-color: #0056b3;
    --button-active-color: #fff;
    --book-section-background-color: #fff;
    --book-title-background-color: #f8f9fa;
    --book-year-color: #6c757d;
    --fold-indicator-color: #6c757d;
    --category-header-color: #495057;
    --border-color: #dee2e6;
    --dot-leader-color: #ced4da;
    --highlight-color: #B8860B;
    --composer-color: #6c757d;
    --shadow-color: rgba(0, 0, 0, 0.05);
}

[data-theme='dark'] {
    --background-color: #121212;
    --text-color: #e0e0e0;
    --header-color: #e0e0e0;
    --input-border-color: #444;
    --input-background-color: #222;
    --button-border-color: #444;
    --button-background-color: #2c2c2c;
    --button-hover-background-color: #3a3a3a;
    --button-active-background-color: #0056b3;
    --button-active-color: #fff;
    --book-section-background-color: #1e1e1e;
    --book-title-background-color: #2c2c2c;
    --book-year-color: #aaa;
    --fold-indicator-color: #aaa;
    --category-header-color: #ccc;
    --border-color: #333;
    --dot-leader-color: #555;
    --highlight-color: #ffeb3b;
    --composer-color: #aaa;
    --shadow-color: rgba(255, 255, 255, 0.05);
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
    margin: 0;
    background-color: var(--background-color);
    color: var(--text-color);
    transition: background-color 0.3s, color 0.3s;
}

/* Support for transparent status bars on mobile */
@supports (padding-top: env(safe-area-inset-top)) {
    body {
        padding-top: env(safe-area-inset-top);
        padding-left: env(safe-area-inset-left);
        padding-right: env(safe-area-inset-right);
        padding-bottom: env(safe-area-inset-bottom);
    }
}

/* PWA installed mode - full screen with status bar overlay */
.pwa-installed {
    padding-top: env(safe-area-inset-top, 20px);
}

/* Remove blue touch highlight on mobile */
* {
    -webkit-tap-highlight-color: transparent;
    -webkit-touch-callout: none;
    -webkit-user-select: none;
    -khtml-user-select: none;
    -moz-user-select: none;
    -ms-user-select: none;
    user-select: none;
}

/* Allow text selection for inputs and content areas */
input, textarea, .song-title, .song-subtitle, .song-composer, .book-name, .book-year {
    -webkit-user-select: text;
    -khtml-user-select: text;
    -moz-user-select: text;
    -ms-user-select: text;
    user-select: text;
}


/* Notification */
.notification {
    position: fixed;
    top: 1rem;
    right: 1rem;
    background: var(--book-section-background-color);
    border: 1px solid var(--border-color);
    border-radius: 4px;
    padding: 1rem;
    box-shadow: 0 2px 10px var(--shadow-color);
    z-index: 1001;
    max-width: 300px;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.notification.show {
    animation: slideIn 0.3s ease;
}

.notification.offline {
    border-left: 4px solid #ff9800;
}

.notification.updated {
    border-left: 4px solid #4caf50;
}

.notification.error {
    border-left: 4px solid #f44336;
}

#notification-message {
    flex: 1;
    font-size: 0.9rem;
}

#notification-close {
    background: none;
    border: none;
    font-size: 1.2rem;
    cursor: pointer;
    color: var(--text-color);
    padding: 0;
    width: 24px;
    height: 24px;
    display: flex;
    align-items: center;
    justify-content: center;
}

#notification-close:hover {
    background: var(--button-hover-background-color);
    border-radius: 50%;
}

@keyframes slideIn {
    from {
        transform: translateX(100%);
        opacity: 0;
    }
    to {
        transform: translateX(0);
        opacity: 1;
    }
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 2em;
}

header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 2em;
}

.header-buttons {
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

h1 {
    color: var(--header-color);
    margin: 0;
}

main {
    display: flex;
    flex-direction: column;
}

#search-container {
    position: relative;
    margin-bottom: 0.8em;
}

#search-input {
    padding: 0.8em;
    width: 100%;
    border: 1px solid var(--input-border-color);
    background-color: var(--input-background-color);
    color: var(--text-color);
    border-radius: 8px;
    box-sizing: border-box;
    font-size: 1em;
}

#clear-search-btn {
    position: absolute;
    right: 7px;
    top: 50%;
    transform: translateY(-50%);
    display: none;
    width: 40px;
    height: 40px;
    font-size: 1.5em;
    padding: 0;
}

#search-history {
    display: none;
    position: absolute;
    width: 100%;
    background-color: var(--input-background-color);
    border: 1px solid var(--input-border-color);
    border-top: none;
    border-radius: 0 0 8px 8px;
    box-sizing: border-box;
    z-index: 10;
    box-shadow: 0 4px 6px var(--shadow-color);
}

.history-item {
    padding: 1em 0.8em;
    cursor: pointer;
    display: flex;
    justify-content: space-between;
    align-items: center;
    position: relative;
}

.remove-history-item {
    position: absolute;
    right: 3px;
    top: 50%;
    transform: translateY(-50%);
    width: 44px;
    height: 44px;
    font-size: 1.5em;
    padding: 0;
}

.remove-history-item:hover,
.remove-history-item:active {
    background-color: rgba(255, 0, 0, 0.1) !important;
    color: #d32f2f !important;
}

.history-item:hover,
.history-item:active {
    background-color: var(--button-hover-background-color);
}

#controls {
    display: flex;
    flex-direction: column;
    gap: 0.5em;
    margin-bottom: 0.8em;
}

#filter-controls {
    overflow-x: auto;
    overflow-y: visible;
    -webkit-overflow-scrolling: touch;
    padding-bottom: 0.5em;
    padding-top: 0.25em;
}

#category-buttons {
    display: flex;
    flex-wrap: nowrap;
    align-items: center;
    gap: 0.5em;
}

#bottom-controls {
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 0.5em;
    flex-wrap: wrap;
}

#sort-controls {
    display: flex;
    gap: 0.75em;
    align-items: center;
    margin-left: auto;
}

#sort-controls label {
    color: var(--text-color);
    font-weight: 500;
}

#sort-select {
    padding: 0.6em 2em 0.6em 1em;
    border: 1px solid var(--button-border-color);
    background-color: var(--button-background-color);
    color: var(--text-color);
    border-radius: 8px;
    cursor: pointer;
    font-size: 1em;
    font-family: inherit;
    transition: background-color 0.2s, border-color 0.2s;
    appearance: none;
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' viewBox='0 0 12 12'%3E%3Cpath fill='%23666' d='M6 9L1 4h10z'/%3E%3C/svg%3E");
    background-repeat: no-repeat;
    background-position: right 0.75em center;
}

#sort-select:hover {
    background-color: var(--button-hover-background-color);
}

#sort-select:focus {
    outline: 2px solid var(--button-active-background-color);
    outline-offset: 2px;
}

/* Chip-like filter buttons */
.filter-chip {
    padding: 0.65em 1em;
    border: 1px solid var(--button-border-color);
    background-color: var(--button-background-color);
    color: var(--text-color);
    border-radius: 20px;
    cursor: pointer;
    font-size: 0.9em;
    transition: all 0.2s ease;
    display: inline-flex;
    align-items: center;
    white-space: nowrap;
}

.filter-chip:hover {
    background-color: var(--button-hover-background-color);
    transform: translateY(-1px);
    box-shadow: 0 2px 4px var(--shadow-color);
}

.filter-chip.selected {
    background-color: var(--button-active-background-color);
    color: var(--button-active-color);
    border-color: var(--button-active-background-color);
    font-weight: 500;
}

#result-count {
    color: var(--book-year-color);
}

.book-section {
    margin-bottom: 0.8em;
    background: var(--book-section-background-color);
    border-radius: 12px;
    box-shadow: 0 2px 8px var(--shadow-color);
    overflow: hidden;
    position: relative;
}

.color-line {
    position: absolute;
    top: 0;
    left: 0;
    width: 10px;
    height: 100%;
}

.book-title {
    color: var(--text-color);
    background-color: var(--book-title-background-color);
    padding: 0.75em 0.75em 0.75em calc(0.75em + 10px);
    margin: 0;
    cursor: pointer;
    display: flex;
    justify-content: space-between;
    align-items: center;
    border-bottom: 1px solid var(--border-color);
    transition: background-color 0.2s;
}

.book-title:hover {
    background-color: var(--button-hover-background-color);
}

.book-title-left {
    display: flex;
    flex-direction: column;
}

.book-name {
    font-weight: bold;
}

.book-year {
    font-size: 0.8em;
    font-weight: normal;
    color: var(--book-year-color);
}

.book-title-right {
    display: flex;
    align-items: center;
    gap: 0.2em;
}

.book-color {
    font-size: 0.8em;
    font-weight: normal;
    color: var(--book-year-color);
    text-align: end;
}

.fold-indicator {
    color: var(--fold-indicator-color);
    transition: transform 0.2s;
    display: flex;
    align-items: center;
    justify-content: center;
    width: 20px;
    height: 20px;
}

.fold-indicator svg {
    display: block;
}

.book-title.expanded .fold-indicator {
    transform: rotate(90deg);
}

.book-content {
    padding: 0 1.5em 1.5em 1.5em;
    background-color: var(--book-section-background-color);
}

.book-content.folded {
    display: none;
}

.category-section h3 {
    color: var(--category-header-color);
    margin-top: 1.5em;
    margin-bottom: 1em;
    font-size: 1.1em;
    border-bottom: 1px solid var(--border-color);
    padding-bottom: 0.5em;
}

.song-list {
    list-style: none;
    padding: 0;
}

.song-item {
    display: flex;
    flex-direction: column;
    padding: 0.75em 0;
    border-bottom: 1px solid var(--border-color);
}

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

.song-main-line {
    display: flex;
    justify-content: space-between;
    align-items: baseline;
}

.song-title-wrapper {
    display: flex;
    align-items: baseline;
}

.song-title {
    font-weight: 500;
}

.song-subtitle {
    font-size: 0.9em;
    color: #6c757d;
    padding-left: 0.5em;
}

.song-page {
    font-weight: bold;
    padding-left: 0.5em;
}

.dot-leader {
    flex-grow: 1;
    border-bottom: 1px dotted var(--dot-leader-color);
    margin: 0 0.5em;
    transform: translateY(-3px);
}

.song-composer {
    font-style: italic;
    color: var(--composer-color);
    font-size: 0.9em;
    padding-top: 0.2em;
}

.song-parts {
    padding-left: 1.5em;
    margin-top: 0.5em;
}

.part-item {
    display: flex;
    justify-content: space-between;
    align-items: baseline;
    font-size: 0.9em;
}

.highlight {
    color: var(--highlight-color);
    font-weight: bold;
    background-color: transparent;
}

.icon-btn {
    background: none;
    border: none;
    cursor: pointer;
    width: 44px;
    height: 44px;
    padding: 0;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--text-color);
    -webkit-tap-highlight-color: transparent;
}

.icon-btn:hover,
.icon-btn:active {
    background-color: var(--button-hover-background-color);
}

#theme-toggle .sun, #theme-toggle .moon {
    transition: display 0.3s;
}

#theme-toggle .sun {
    display: block;
}
#theme-toggle .moon {
    display: none;
}

[data-theme='dark'] #theme-toggle .sun {
    display: none;
}

[data-theme='dark'] #theme-toggle .moon {
    display: block;
}

#scroll-to-top-btn {
    position: fixed;
    bottom: 20px;
    right: 20px;
    display: none;
    background-color: var(--button-active-background-color);
    color: var(--button-active-color);
    border: none;
    border-radius: 50%;
    width: 48px;
    height: 48px;
    cursor: pointer;
    z-index: 100;
    box-shadow: 0 4px 12px rgba(0,0,0,0.15);
    transition: all 0.3s ease;
    padding: 0;
    display: flex;
    align-items: center;
    justify-content: center;
}

#scroll-to-top-btn:hover,
#scroll-to-top-btn:active {
    opacity: 0.8;
}

#scroll-to-top-btn svg {
    transition: transform 0.2s ease;
}

@media (max-width: 600px) {
    .container {
        padding: 1em;
    }

    header {
        margin-bottom: 1.5em;
    }

    h1 {
        font-size: 1.5em;
    }

    .book-title, .book-content {
        padding: 0.5em 0.5em 0.5em calc(0.5em + 10px)
    }

    .song-main-line {
        flex-wrap: wrap;
    }

    .dot-leader {
        display: none;
    }

    .song-page {
        margin-left: auto;
    }
}