:root {
    --z-toolbar: 1000;
    --z-modal-overlay: 2000;
    --z-chapter-title: 5;

    --radius-sm: 4px;
    --radius-md: 8px;
    --radius-lg: 12px;
    --radius-xl: 16px;

    --hl-yellow-bg: rgba(255, 235, 59, 0.4);
    --hl-yellow-border: #fbc02d;
    --hl-yellow-text: inherit;

    --hl-green-bg: rgba(76, 175, 80, 0.3);
    --hl-green-border: #43a047;
    --hl-green-text: inherit;

    --hl-blue-bg: rgba(33, 150, 243, 0.3);
    --hl-blue-border: #1e88e5;
    --hl-blue-text: inherit;

    --hl-red-bg: rgba(244, 67, 54, 0.3);
    --hl-red-border: #e53935;
    --hl-red-text: inherit;

    --icon-note-mask: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24'%3E%3Cpath d='M14 2H6a2 2 0 0 0-2 2v16a2 2 0 0 0 2 2h12a2 2 0 0 0 2-2V8l-6-6zm2 16H8v-2h8v2zm0-4H8v-2h8v2zm-3-5V3.5L18.5 9H13z'/%3E%3C/svg%3E");
}

[data-theme="dark"] {
    --hl-yellow-bg: rgba(255, 235, 59, 0.25);
    --hl-yellow-text: #fff;
    --hl-green-bg: rgba(76, 175, 80, 0.25);
    --hl-green-text: #fff;
    --hl-blue-bg: rgba(33, 150, 243, 0.25);
    --hl-blue-text: #fff;
    --hl-red-bg: rgba(244, 67, 54, 0.25);
    --hl-red-text: #fff;
}

[data-theme="sepia"] {
    --hl-yellow-bg: rgba(215, 165, 50, 0.3);
    --hl-yellow-border: #bfa050;
    --hl-green-bg: rgba(100, 130, 90, 0.25);
    --hl-green-border: #6b8e23;
    --hl-blue-bg: rgba(80, 110, 130, 0.25);
    --hl-blue-border: #5f9ea0;
    --hl-red-bg: rgba(200, 90, 80, 0.25);
    --hl-red-border: #cd5c5c;
}

[data-theme="midnight"] {
    --hl-yellow-bg: rgba(255, 215, 0, 0.2);
    --hl-yellow-text: #e0e6ed;
    --hl-green-bg: rgba(100, 255, 218, 0.15);
    --hl-green-text: #e0e6ed;
    --hl-blue-bg: rgba(130, 177, 255, 0.2);
    --hl-blue-text: #e0e6ed;
    --hl-red-bg: rgba(255, 138, 128, 0.2);
    --hl-red-text: #e0e6ed;
}

[data-theme="forest"] {
    --hl-yellow-bg: rgba(255, 235, 59, 0.5);
    --hl-yellow-border: #f9a825;
    --hl-green-bg: rgba(56, 142, 60, 0.25);
    --hl-green-border: #2e7d32;
    --hl-blue-bg: rgba(3, 169, 244, 0.25);
    --hl-blue-border: #0288d1;
    --hl-red-bg: rgba(239, 83, 80, 0.3);
    --hl-red-border: #c62828;
}

[data-theme="amoled"] {
    --hl-yellow-bg: rgba(255, 255, 0, 0.3);
    --hl-yellow-text: #fff;
    --hl-yellow-border: none;

    --hl-green-bg: rgba(0, 255, 64, 0.25);
    --hl-green-text: #fff;
    --hl-green-border: none;

    --hl-blue-bg: rgba(0, 140, 255, 0.3);
    --hl-blue-text: #fff;
    --hl-blue-border: none;

    --hl-red-bg: rgba(255, 30, 30, 0.3);
    --hl-red-text: #fff;
    --hl-red-border: none;
}

.highlight {
    cursor: pointer;
    border-radius: 2px;
    transition:
        background-color 0.2s,
        border-color 0.2s;
    color: inherit;
}

.highlight-yellow {
    background-color: var(--hl-yellow-bg);
    border-bottom: 2px solid var(--hl-yellow-border);
    color: var(--hl-yellow-text);
}

.highlight-green {
    background-color: var(--hl-green-bg);
    border-bottom: 2px solid var(--hl-green-border);
    color: var(--hl-green-text);
}

.highlight-blue {
    background-color: var(--hl-blue-bg);
    border-bottom: 2px solid var(--hl-blue-border);
    color: var(--hl-blue-text);
}

.highlight-red {
    background-color: var(--hl-red-bg);
    border-bottom: 2px solid var(--hl-red-border);
    color: var(--hl-red-text);
}

.highlight.has-note-icon::after {
    content: "";
    display: inline-block;
    width: 12px;
    height: 12px;
    margin-left: 3px;
    vertical-align: -1px;
    background-color: var(--accent-color);
    opacity: 1;
    -webkit-mask: var(--icon-note-mask) no-repeat center / contain;
    mask: var(--icon-note-mask) no-repeat center / contain;
}

.icon-btn {
    background: transparent;
    border: none;
    cursor: pointer;
    color: var(--text-color);
    opacity: 0.7;
    padding: 6px;
    border-radius: var(--radius-sm);
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all 0.2s;
    flex-shrink: 0;
}

.icon-btn svg {
    width: 18px;
    height: 18px;
}

.icon-btn:hover {
    background-color: var(--hover-bg);
    opacity: 1;
    transform: translateY(-1px);
}

.icon-btn.delete-btn:hover {
    color: #e53935;
    background-color: rgba(229, 57, 53, 0.1);
}

.icon-btn.copy-btn {
    margin-top: -2px;
}

.icon-btn.copy-btn .icon-check {
    display: none;
    color: #43a047;
}

.icon-btn.copy-btn.copied .icon-copy {
    display: none;
}

.icon-btn.copy-btn.copied .icon-check {
    display: block;
}

.icon-btn.note-btn:hover {
    color: var(--accent-color);
}

#highlight-toolbar {
    position: absolute;
    z-index: var(--z-toolbar);
    display: none;
    background-color: var(--menu-bg);
    backdrop-filter: blur(8px);
    -webkit-backdrop-filter: blur(8px);
    border: 1px solid var(--border-color);
    box-shadow: 0 8px 20px -4px var(--shadow-color);
    padding: 6px 10px;
    border-radius: var(--radius-lg);
    gap: 12px;
    align-items: center;
    flex-direction: row;
    animation: popIn 0.2s cubic-bezier(0.175, 0.885, 0.32, 1.275);
    -webkit-user-select: none;
    user-select: none;
}

#highlight-toolbar .icon-btn.delete-btn {
    display: none;
}

#highlight-toolbar.edit-mode .icon-btn.delete-btn {
    display: flex;
}

.hl-group {
    display: flex;
    align-items: center;
    gap: 6px;
}

.hl-divider {
    width: 1px;
    height: 18px;
    background-color: var(--border-color);
    opacity: 0.6;
}

.hl-btn-color {
    width: 20px;
    height: 20px;
    border-radius: 50%;
    border: 1px solid rgba(0, 0, 0, 0.1);
    cursor: pointer;
    transition:
        transform 0.15s ease,
        box-shadow 0.15s ease;
    padding: 0;
}

.hl-btn-color:hover {
    transform: scale(1.15);
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
}

.hl-btn-yellow {
    background-color: #fbc02d;
}

.hl-btn-green {
    background-color: #43a047;
}

.hl-btn-blue {
    background-color: #1e88e5;
}

.hl-btn-red {
    background-color: #e53935;
}

.modal-overlay {
    position: fixed;
    inset: 0;
    background: rgba(0, 0, 0, 0.4);
    backdrop-filter: blur(2px);
    -webkit-backdrop-filter: blur(2px);
    z-index: var(--z-modal-overlay);
    display: flex;
    align-items: center;
    justify-content: center;
    opacity: 0;
    visibility: hidden;
    transition:
        opacity 0.2s ease,
        visibility 0.2s;
}

.modal-overlay.active {
    opacity: 1;
    visibility: visible;
}

.modal {
    background: var(--bg-color);
    color: var(--text-color);
    width: 90%;
    max-width: 420px;
    padding: 24px;
    border-radius: var(--radius-xl);
    box-shadow: 0 20px 50px rgba(0, 0, 0, 0.15);
    border: 1px solid var(--border-color);
    display: flex;
    flex-direction: column;
    gap: 16px;
    transform: scale(0.95) translateY(10px);
    opacity: 0;
    transition:
        transform 0.15s cubic-bezier(0.175, 0.885, 0.32, 1.275),
        opacity 0.05s;
}

.modal-overlay.active .modal {
    transform: scale(1) translateY(0);
    opacity: 1;
}

.modal h3 {
    margin: 0;
    font-size: 1.1rem;
    font-weight: 600;
    opacity: 0.9;
}

.modal textarea {
    background: var(--input-bg);
    color: var(--text-color);
    border: 1px solid var(--border-color);
    padding: 16px;
    border-radius: var(--radius-lg);
    resize: vertical;
    min-height: 120px;
    font-family: inherit;
    font-size: 15px;
    line-height: 1.6;
    outline: none;
    appearance: none;
    box-shadow: inset 0 2px 4px rgba(0, 0, 0, 0.03);
    transition:
        border-color 0.2s ease,
        box-shadow 0.2s ease,
        background-color 0.2s;
    scrollbar-width: thin;
    scrollbar-color: var(--border-color) transparent;
}

.modal textarea:hover {
    background-color: var(--menu-bg);
}

.modal textarea:focus {
    border-color: var(--accent-color);
    background-color: var(--bg-color);
    box-shadow:
        0 0 0 4px var(--hover-bg),
        0 4px 12px rgba(0, 0, 0, 0.05);
}

.modal textarea::placeholder {
    color: var(--text-color);
    opacity: 0.4;
    font-weight: 400;
}

.modal textarea::-webkit-scrollbar {
    width: 8px;
}

.modal textarea::-webkit-scrollbar-track {
    background: transparent;
}

.modal textarea::-webkit-scrollbar-thumb {
    background-color: var(--border-color);
    border-radius: 4px;
    border: 2px solid transparent;
    background-clip: content-box;
}

.modal textarea::-webkit-scrollbar-thumb:hover {
    background-color: var(--text-color);
}

.modal textarea::-webkit-resizer {
    background-color: transparent;
    background-image: linear-gradient(
        135deg,
        transparent 80%,
        var(--text-color) 80%
    );
    opacity: 0.3;
    background-size: 100% 100%;
    border-radius: 0 0 12px 0;
}

.modal-actions {
    display: flex;
    justify-content: flex-end;
    gap: 10px;
}

.modal .ui-button {
    padding: 8px 16px;
    font-size: 14px;
    border: none;
    border-radius: var(--radius-md);
    cursor: pointer;
    font-weight: 600;
    transition:
        transform 0.1s,
        opacity 0.2s;
}

.modal .ui-button:active {
    transform: scale(0.96);
}

.btn-secondary {
    background: transparent;
    color: var(--text-color);
    opacity: 0.7;
    border: 1px solid transparent;
}

.btn-secondary:hover {
    background: var(--hover-bg);
    opacity: 1;
}

.btn-primary {
    background: var(--text-color);
    color: var(--bg-color);
    box-shadow: 0 4px 12px var(--shadow-color);
}

.btn-primary:hover {
    opacity: 0.9;
    box-shadow: 0 6px 16px var(--shadow-color);
}

.overview-modal {
    max-width: 600px;
    height: 80vh;
    padding: 0;
    overflow: hidden;
}

.overview-modal .modal-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 16px 24px;
    border-bottom: 1px solid var(--border-color);
    background: var(--menu-bg);
    flex-shrink: 0;
}

.overview-controls {
    padding: 12px 24px;
    border-bottom: 1px solid var(--border-color);
    background: var(--menu-bg);
    display: flex;
    gap: 16px;
    align-items: center;
    flex-shrink: 0;
    z-index: 10;
}

.search-wrapper {
    position: relative;
    flex: 1;
    display: flex;
    align-items: center;
    background: var(--input-bg);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    transition:
        border-color 0.2s,
        box-shadow 0.2s;
    min-width: 0;
    overflow: hidden;
}

.search-wrapper:focus-within {
    border-color: var(--accent-color);
    box-shadow: 0 0 0 2px var(--hover-bg);
}

.search-icon {
    position: absolute;
    left: 12px;
    color: var(--text-color);
    opacity: 0.5;
    pointer-events: none;
}

.overview-controls input {
    flex: 1;
    width: 100%;
    padding: 10px 12px 10px 36px;
    border: none;
    background: transparent;
    color: var(--text-color);
    font-family: inherit;
    font-size: 14px;
    outline: none !important;
}

.sort-group {
    display: flex;
    background: var(--input-bg);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    padding: 3px;
    gap: 2px;
}

.sort-btn {
    border-radius: calc(var(--radius-md) - 3px);
    padding: 6px 10px;
    opacity: 0.5;
    transition: all 0.2s ease;
}

.sort-btn:hover {
    opacity: 0.8;
}

.sort-btn.active {
    background: var(--hover-bg);
    color: var(--text-color);
    opacity: 1;
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.05);
}

.overview-content {
    overflow-y: auto;
    height: 100%;
    padding: 0;
    overscroll-behavior: contain;
}

.overview-empty {
    padding: 40px;
    text-align: center;
    opacity: 0.6;
    font-style: italic;
}

.hl-chapter-group {
    border-bottom: 1px solid var(--border-color);
}

.hl-chapter-title {
    background: var(--menu-bg);
    padding: 12px 24px;
    font-weight: 700;
    font-size: 0.9rem;
    color: var(--text-color);
    opacity: 0.9;
    position: sticky;
    top: 0;
    z-index: var(--z-chapter-title);
    border-bottom: 1px solid var(--border-color);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.hl-chapter-link {
    font-size: 0.8rem;
    text-decoration: none;
    color: var(--accent-color);
    border: 1px solid var(--border-color);
    padding: 2px 8px;
    border-radius: 12px;
}

.hl-item {
    padding: 16px 24px;
    border-bottom: 1px solid var(--border-color);
    transition: background 0.1s;
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.hl-item:hover {
    background: var(--hover-bg);
}

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

.hl-top-row {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    gap: 12px;
}

.hl-actions {
    display: flex;
    gap: 4px;
    flex-shrink: 0;
    margin-top: -2px;
}

.hl-quote {
    font-family: var(--font-family);
    border-left: 3px solid transparent;
    padding-left: 10px;
    font-size: 0.95em;
    color: var(--text-color);
    line-height: 1.5;
    flex: 1;
}

.hl-quote.yellow {
    border-color: var(--hl-yellow-border);
}

.hl-quote.green {
    border-color: var(--hl-green-border);
}

.hl-quote.blue {
    border-color: var(--hl-blue-border);
}

.hl-quote.red {
    border-color: var(--hl-red-border);
}

.hl-user-note {
    font-size: 0.9em;
    background: var(--input-bg);
    padding: 8px 12px;
    border-radius: 6px;
    color: var(--text-color);
    margin-top: 4px;
    position: relative;
}

.hl-user-note::before {
    content: "NOTE:";
    font-size: 0.7em;
    font-weight: bold;
    opacity: 0.5;
    display: block;
    margin-bottom: 2px;
}

@keyframes popIn {
    from {
        opacity: 0;
        transform: translateY(10px) scale(0.9);
    }

    to {
        opacity: 1;
        transform: translateY(0) scale(1);
    }
}

@media (max-width: 768px) {
    .modal-overlay {
        align-items: flex-start;
        padding-top: 80px;
        overflow-y: auto;
    }

    .modal {
        max-height: calc(100vh - 100px);
        overflow-y: auto;
    }

    #overviewOverlay {
        padding: 0;
        align-items: stretch;
        background: var(--bg-color);
    }

    #overviewOverlay .overview-modal {
        width: 100%;
        max-width: none;
        height: 100%;
        max-height: none;
        border-radius: 0;
        border: none;
        box-shadow: none;
        transform: none !important;
        opacity: 1;
    }

    #overviewOverlay .modal-header {
        padding: 16px 20px;
        position: sticky;
        top: 0;
        z-index: 10;
    }

    .hl-item {
        padding: 20px;
    }
}

@media (max-width: 480px) {
    .overview-controls {
        flex-direction: column;
        padding: 12px 16px;
    }
}