:root {
    --bg-color: #1a1a1d;
    --sidebar-bg: #121214;
    --input-bg: #1f1f22;
    --text-color: #e4e4e7;
    --text-light: rgba(228, 228, 231, 0.6);
    --user-msg-bg: #2a2a2f;
    --bot-msg-bg: #1a1a1d;
    --accent-color: #ffffff;
    --border-color: rgba(255, 255, 255, 0.05);
    --shadow-color: rgba(0, 0, 0, 0.5);
    --user-avatar-bg: #ffffff;
    --bot-avatar-bg: #2e2e33;
    --hover-bg: rgba(255, 255, 255, 0.1);
    --light-border: 1px solid rgba(255, 255, 255, 0.05);
    --subtle-radius: 6px;
}

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

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
    background: var(--bg-color);
    color: var(--text-color);
    height: 100vh;
    line-height: 1.6;
}

/* --- Sidebar --- */
.sidebar {
    width: 260px;
    background-color: var(--sidebar-bg);
    border-right: 1px solid var(--border-color);
    transition: all 0.3s ease;
    position: fixed;
    left: 0;
    top: 0;
    bottom: 0;
    z-index: 100;
    display: flex;
    flex-direction: column;
    height: 100%;
    box-shadow: 0 0 10px var(--shadow-color);
}

.new-chat-btn {
    background-color: var(--accent-color);
    color: #000000;
    border: none;
    border-radius: 6px;
    padding: 12px 16px;
    margin: 14px 10px;
    display: flex;
    align-items: center;
    gap: 10px;
    transition: all 0.2s ease;
    text-align: left;
    cursor: pointer;
    width: calc(100% - 80px);
    font-weight: 500;
    box-shadow: 0 4px 10px rgba(0, 0, 0, 0.4);
}

.new-chat-btn:hover {
    background-color: #e6e6e6;
    transform: translateY(-1px);
    box-shadow: 0 6px 14px rgba(0, 0, 0, 0.5);
}

.new-chat-btn:active {
    transform: translateY(0);
    background-color: #d9d9d9;
    box-shadow: 0 2px 6px rgba(0, 0, 0, 0.4);
}

.chat-history {
    flex: 1;
    overflow-y: auto;
    padding: 8px;
    scrollbar-width: thin;
    scrollbar-color: var(--border-color) transparent;
}

.chat-history::-webkit-scrollbar {
    width: 5px;
}

.chat-history::-webkit-scrollbar-track {
    background: transparent;
}

.chat-history::-webkit-scrollbar-thumb {
    background-color: var(--border-color);
    border-radius: 10px;
}

.chat-section-header {
    color: var(--text-light);
    font-size: 0.75rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    padding: 16px 12px 8px;
    margin-top: 4px;
}

.chat-section-header:first-child {
    margin-top: 0;
}

.chat-item {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 10px 12px;
    padding-right: 40px;
    width: 100%;
    background: transparent;
    border: none;
    border-radius: 6px;
    color: var(--text-light);
    cursor: pointer;
    text-align: left;
    transition: all 0.2s ease;
    position: relative;
    margin-bottom: 2px;
    font-size: 0.9rem;
}

.chat-item:hover {
    background-color: var(--hover-bg);
    color: var(--text-color);
}

.chat-item.active {
    background-color: var(--hover-bg);
    color: var(--text-color);
    border-left: 3px solid var(--accent-color);
}

.chat-item i {
    font-size: 0.9rem;
    opacity: 0.8;
}

.chat-title {
    flex: 1;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
    font-size: 0.85rem;
    min-width: 0;
    padding: 2px 4px;
    border-radius: var(--subtle-radius);
    line-height: 1.4;
    transition: color 0.2s ease;
}

.chat-title-edit-input {
    flex-grow: 1;
    background: var(--input-bg);
    border: 1px solid var(--accent-color);
    color: var(--text-color);
    padding: 2px 5px;
    border-radius: 4px;
    font-size: 0.85rem;
    margin-right: 5px;
    outline: none;
}

.chat-item-actions {
    position: absolute;
    right: 10px;
    top: 50%;
    transform: translateY(-50%);
    z-index: 10;
}

.chat-buttons {
    display: flex;
    gap: 4px;
    margin-left: auto;
    opacity: 0;
    transition: opacity 0.2s ease;
}

.chat-item:hover .chat-buttons {
    opacity: 1;
}

.chat-menu-btn {
    background: none;
    border: none;
    color: var(--text-color);
    cursor: pointer;
    padding: 4px;
    opacity: 0.7;
    transition: all 0.2s ease;
    border-radius: var(--subtle-radius);
}

.chat-menu-btn:hover {
    opacity: 1;
    background-color: var(--hover-bg);
}

.chat-dropdown-menu {
    position: absolute;
    right: 0;
    top: 32px;
    background-color: #1a1a1a;
    border: 1px solid #333;
    border-radius: 6px;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 1);
    overflow: hidden;
    width: 160px;
    z-index: 9999;
}

.chat-dropdown-menu::backdrop,
.chat-dropdown-menu * {
    backdrop-filter: none !important;
}

.dropdown-item {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 10px 14px;
    color: var(--text-color);
    background-color: #1a1a1a;
    border: none;
    width: 100%;
    text-align: left;
    cursor: pointer;
    transition: background-color 0.2s;
    font-size: 0.92rem;
}

.dropdown-item:hover {
    background-color: #2d2d2d;
}

.dropdown-item i {
    font-size: 0.9rem;
    width: 14px;
}

/* --- Main Content --- */
.main-content {
    background-color: var(--bg-color);
    flex-grow: 1;
    margin-left: 260px;
    display: flex;
    flex-direction: column;
    height: 100vh;
    width: calc(100% - 260px);
    position: relative;
}

.top-bar {
    border-bottom: 1px solid var(--border-color);
    padding: 12px 20px;
    display: flex;
    align-items: center;
    gap: 8px;
    background-color: var(--bg-color);
    flex-shrink: 0;
    position: sticky;
    top: 0;
    z-index: 50;
    box-shadow: 0 1px 5px rgba(0, 0, 0, 0.15);
}

.mobile-menu-btn {
    display: none;
}

.top-bar-action-btn {
    background: none;
    border: none;
    color: var(--text-color);
    cursor: pointer;
    padding: 8px;
    border-radius: 4px;
    font-size: 20px;
    transition: background-color 0.2s;
    flex-shrink: 0;
}

.top-bar-action-btn:hover {
    background-color: var(--hover-bg);
}

.server-url-input {
    background-color: var(--input-bg);
    border: 1px solid var(--border-color);
    color: var(--text-color);
    padding: 10px 14px;
    border-radius: 6px;
    outline: none;
    font-size: 0.9rem;
    transition: all 0.2s ease;
    flex-grow: 1;
    min-width: 100px;
}

.server-url-input:hover,
.server-url-input:focus {
    border-color: rgba(255, 255, 255, 0.3);
    box-shadow: 0 1px 4px rgba(0, 0, 0, 0.2);
}

.model-selector {
    background-color: var(--input-bg);
    border: 1px solid var(--border-color);
    color: var(--text-color);
    padding: 10px 14px;
    border-radius: 6px;
    outline: none;
    font-size: 0.92rem;
    cursor: pointer;
    transition: all 0.2s ease;
    appearance: none;
    -webkit-appearance: none;
    background-image: url('data:image/svg+xml;utf8,<svg xmlns="http://www.w3.org/2000/svg" width="12" height="12" viewBox="0 0 24 24" fill="none" stroke="white" stroke-width="2" stroke-linecap="round" stroke-linejoin="round"><path d="M6 9l6 6 6-6"/></svg>');
    background-repeat: no-repeat;
    background-position: right 12px center;
    padding-right: 30px;
    flex-shrink: 0;
    min-width: 150px;
}

.model-selector:hover,
.model-selector:focus {
    border-color: rgba(255, 255, 255, 0.3);
    box-shadow: 0 1px 4px rgba(0, 0, 0, 0.2);
}

.chat-container {
    flex: 1;
    position: relative;
    overflow: hidden;
}

.scroll-container {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    overflow-y: auto;
}

.scroll-container::-webkit-scrollbar {
    width: 8px;
    position: absolute;
    right: 0;
}

.scroll-container::-webkit-scrollbar-track {
    background: transparent;
}

.scroll-container::-webkit-scrollbar-thumb {
    background-color: var(--border-color);
    border-radius: 4px;
}

.messages {
    max-width: 900px;
    margin: 0 auto;
    width: 100%;
    display: flex;
    flex-direction: column;
    gap: 0;
}

.welcome-screen {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    min-height: 60vh;
    text-align: center;
    gap: 24px;
    margin: auto;
    max-width: 650px;
    padding: 20px;
}

.welcome-screen h2 {
    font-size: 2rem;
    font-weight: 600;
    color: white;
    margin-bottom: 10px;
}

.welcome-screen p {
    font-size: 1.1rem;
    color: var(--text-light);
    line-height: 1.5;
    max-width: 500px;
}

.welcome-screen .avatar {
    width: 60px;
    height: 60px;
    font-size: 2rem;
    background-color: var(--accent-color);
    border-radius: 50%;
    margin-bottom: 10px;
}

/* --- Messages & Content --- */
.message {
    display: flex;
    padding: 16px 20px;
    opacity: 0;
    transform: translateY(10px);
    animation: message-appear 0.3s ease forwards;
    width: 100%;
    box-sizing: border-box;
    position: relative;
}

@keyframes message-appear {
    from {
        opacity: 0;
        transform: translateY(10px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.avatar {
    display: none;
}

.message-timestamp {
    font-size: 12px;
    color: var(--text-light);
    opacity: 0.7;
    margin-bottom: 4px;
}

.bot-message {
    background-color: var(--bot-msg-bg);
}

.bot-message .message-content {
    flex: 1;
    max-width: 750px;
    margin: 0 auto;
    position: relative;
    font-size: 15px;
    padding: 0;
}

.user-message {
    background-color: transparent;
    justify-content: flex-end;
}

.user-message .message-content {
    background-color: var(--user-msg-bg);
    border-radius: 10px;
    padding: 5px 10px;
    max-width: 750px;
    font-size: 15px;
    position: relative;
    min-width: 100px;
}

.user-message .message-content p {
    margin-top: 4px;
    margin-bottom: 4px;
}

.user-message .message-timestamp {
    text-align: right;
    margin-right: 4px;
    justify-content: flex-end;
}

.message-actions {
    position: static;
    opacity: 1;
    transform: none;
    margin-top: 10px;
    display: flex;
    gap: 10px;
}

.user-message .message-actions {
    justify-content: flex-end;
}

.message-content:hover .message-actions {
    opacity: 1;
}

.message-action-btn {
    background-color: rgba(255, 255, 255, 0.05);
    border: 1px solid var(--border-color);
    border-radius: 6px;
    padding: 5px 10px;
    opacity: 0.8;
    font-size: 13px;
    display: flex;
    align-items: center;
    gap: 6px;
    color: var(--text-light);
    cursor: pointer;
    transition: all 0.2s ease;
}

.message-action-btn:hover {
    opacity: 1;
    background-color: rgba(255, 255, 255, 0.1);
}

.message .message-actions .edit-message-btn,
.message .message-actions .regenerate-btn,
.message:not(:hover) .tts-btn {
    opacity: 0;
    transition: opacity 0.2s ease-in-out;
    pointer-events: none;
}

.message:hover .message-actions .edit-message-btn,
.message:hover .message-actions .regenerate-btn {
    opacity: 1;
    pointer-events: auto;
}

.user-edit-container {
    display: flex;
    flex-direction: column;
    gap: 8px;
    width: 100%;
    margin-top: 5px;
}

.edit-message-textarea {
    width: 100%;
    min-height: 80px;
    max-height: 400px;
    padding: 10px;
    border-radius: 8px;
    border: 1px solid #444;
    background-color: #2c2c2e;
    color: #f0f0f0;
    font-family: inherit;
    font-size: 0.95rem;
    resize: vertical;
    box-sizing: border-box;
}

.edit-message-textarea:focus {
    outline: none;
    border-color: #FFFFFF;
    box-shadow: 0 0 0 2px rgba(255, 255, 255, 0.25);
}

.edit-actions-container {
    display: flex;
    justify-content: flex-end;
    align-items: center;
    gap: 10px;
}

.edit-action-btn {
    display: flex;
    align-items: center;
    gap: 6px;
    padding: 6px 12px;
    border: none;
    border-radius: 6px;
    font-size: 0.85rem;
    font-weight: 500;
    cursor: pointer;
    transition: background-color 0.2s, color 0.2s, opacity 0.2s;
    color: #f0f0f0;
}

.edit-action-btn i {
    font-size: 0.9em;
}

.edit-action-btn.cancel-edit-btn {
    background-color: #d1d1d6;
    color: #000000;
}

.edit-action-btn.cancel-edit-btn:hover {
    background-color: #b9b9be;
}

.edit-action-btn.save-regenerate-btn {
    background-color: #444;
}

.edit-action-btn.save-regenerate-btn:hover {
    background-color: #555;
}

#typing-animation {
    padding: 16px 20px;
    background-color: var(--bot-msg-bg);
    display: none;
}

.typing-container {
    max-width: 750px;
    margin: 0;
    display: flex;
    align-items: center;
}

.typing-dots {
    display: flex;
    gap: 4px;
    margin-left: 0;
}

.typing-dot {
    width: 5px;
    height: 5px;
    background: var(--text-light);
    border-radius: 50%;
    animation: typing 1.4s infinite ease-in-out;
    opacity: 0.7;
}

.typing-dot:nth-child(2) {
    animation-delay: 0.2s;
}

.typing-dot:nth-child(3) {
    animation-delay: 0.4s;
}

@keyframes typing {
    0%,
    100% {
        transform: translateY(0);
    }
    50% {
        transform: translateY(-4px);
    }
}

/* --- Markdown & Content Formatting --- */
.message-content {
    line-height: 1.6;
}

.message-content h1,
.message-content h2,
.message-content h3,
.message-content h4,
.message-content h5,
.message-content h6 {
    margin: 1.5em 0 0.5em;
    font-weight: 600;
}

.message-content h1 {
    font-size: 2em;
}
.message-content h2 {
    font-size: 1.5em;
}
.message-content h3 {
    font-size: 1.17em;
}
.message-content h4 {
    font-size: 1em;
}

.message-content p {
    margin: 1em 0;
}

.message-content ul,
.message-content ol {
    margin: 1em 0;
    padding-left: 2em;
}

.message-content li {
    margin: 0.5em 0;
}

.message-content a {
    color: var(--accent-color) !important;
    text-decoration: underline;
}

.message-content a:hover {
    color: #ffcc00;
}

.message-content blockquote {
    margin: 1em 0;
    padding-left: 1em;
    border-left: 4px solid var(--accent-color);
    color: rgba(255, 255, 255, 0.8);
}

.message-content table {
    width: 100%;
    margin: 1em 0;
    border-collapse: collapse;
}

.message-content th,
.message-content td {
    padding: 8px 12px;
    border: 1px solid var(--border-color);
}

.message-content th {
    background: rgba(255, 255, 255, 0.1);
    font-weight: 600;
}

.message-content img.user-uploaded-image {
    max-width: 300px;
    max-height: 300px;
    border-radius: 8px;
    margin-top: 8px;
    border: 1px solid var(--border-color);
    object-fit: contain;
}

.message-content img {
    max-width: 100%;
    height: auto;
    border-radius: 4px;
    margin-top: 8px;
}

/* --- Code Blocks --- */
.message-content pre {
    background: #1a1a1a;
    border-radius: 8px;
    margin: 1.2em 0;
    overflow: hidden;
    position: relative;
    padding-top: 36px !important;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.3);
    border: 1px solid rgba(255, 255, 255, 0.1);
}

.code-block-header {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 36px;
    background: #2d2d2d;
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0 12px;
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}

.code-language {
    color: rgba(255, 255, 255, 0.7);
    font-size: 11px;
    text-transform: uppercase;
    font-weight: 600;
    letter-spacing: 0.5px;
}

.code-copy-btn {
    background: rgba(255, 255, 255, 0.08);
    border: 1px solid rgba(255, 255, 255, 0.15);
    border-radius: 4px;
    color: rgba(255, 255, 255, 0.85);
    padding: 4px 10px;
    font-size: 12px;
    cursor: pointer;
    display: flex;
    align-items: center;
    gap: 6px;
    transition: all 0.2s ease;
    height: 26px;
}

.code-copy-btn:hover {
    background: rgba(255, 255, 255, 0.15);
    border-color: rgba(255, 255, 255, 0.25);
    transform: translateY(-1px);
}

.code-copy-btn:active {
    transform: translateY(0);
}

.code-copy-btn i {
    font-size: 12px;
}

.code-copy-btn.copied {
    background: var(--accent-color);
    border-color: var(--accent-color);
    color: black;
}

.message-content pre code {
    display: block;
    padding: 16px;
    overflow-x: auto;
    font-family: 'Fira Code', 'Consolas', 'Monaco', 'Andale Mono', monospace;
    font-size: 14px;
    line-height: 1.6;
    color: #e6e6e6;
    background: transparent;
    border: none;
    max-height: 500px;
}

.message-content pre code::-webkit-scrollbar {
    height: 8px;
    width: 8px;
}

.message-content pre code::-webkit-scrollbar-track {
    background: rgba(0, 0, 0, 0.2);
    border-radius: 4px;
}

.message-content pre code::-webkit-scrollbar-thumb {
    background: rgba(255, 255, 255, 0.2);
    border-radius: 4px;
}

.message-content pre code::-webkit-scrollbar-thumb:hover {
    background: rgba(255, 255, 255, 0.3);
}

.token.comment,
.token.prolog,
.token.doctype,
.token.cdata {
    color: #708090;
}

.token.operator,
.token.punctuation {
    color: #d4d4d4;
}

.token.tag,
.token.attr-name {
    color: #e6db74;
}

.token.attr-value,
.token.string {
    color: #a6e22e;
}

.token.keyword {
    color: #f92672;
}

.token.number {
    color: #ae81ff;
}

.token.boolean,
.token.constant {
    color: #66d9ef;
}

.token.function {
    color: #a6e22e;
}

.token.class-name {
    color: #66d9ef;
}

.token.selector {
    color: #a6e22e;
}

.token.operator.logical,
.token.operator.relational {
    color: #f92672;
}

.token.entity,
.token.url {
    color: #ae81ff;
}

.token.variable {
    color: #a6e22e;
}

.token.inserted {
    background-color: hsla(100, 100%, 50%, 0.1);
    text-decoration: none !important;
}

.token.deleted {
    background-color: hsla(0, 100%, 50%, 0.1);
    text-decoration: line-through !important;
}

/* --- Bottom Input Bar --- */
.bottom-bar {
    background-color: var(--bg-color);
    border-top: 1px solid var(--border-color);
    padding: 10px 20px;
    position: sticky;
    bottom: 0;
    box-shadow: 0 -2px 10px rgba(0, 0, 0, 0.1);
    z-index: 100;
}

.input-area-container {
    max-width: 700px;
    margin: 0 auto;
    background-color: var(--input-bg);
    border: 1px solid var(--border-color);
    border-radius: 15px;
    box-shadow: 0 2px 6px rgba(0, 0, 0, 0.15);
    transition: all 0.2s ease;
}

.input-area-container:focus-within {
    border-color: rgba(255, 255, 255, 0.5);
    box-shadow: 0 2px 10px rgba(255, 255, 255, 0.1);
}

#image-preview-container {
    padding: 10px 15px 5px;
    display: none;
    position: relative;
}

#image-preview {
    max-width: 100px;
    max-height: 100px;
    border-radius: 6px;
    border: 1px solid var(--border-color);
    object-fit: cover;
}

#remove-image-btn {
    position: absolute;
    top: 2px;
    right: 2px;
    background: rgba(0, 0, 0, 0.6);
    color: white;
    border: none;
    border-radius: 50%;
    width: 20px;
    height: 20px;
    font-size: 10px;
    line-height: 20px;
    text-align: center;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
}

#remove-image-btn:hover {
    background: rgba(0, 0, 0, 0.8);
}

.input-wrapper {
    display: flex;
    align-items: flex-end;
    padding: 10px 15px;
    gap: 10px;
}

.input-area {
    flex: 1;
    display: flex;
    align-items: center;
}

#message-input {
    width: 100%;
    background: transparent;
    border: none;
    color: var(--text-color);
    resize: none;
    font-size: 16px;
    outline: none;
    line-height: 1.5;
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
    padding: 8px 4px;
    max-height: 120px;
    min-height: 24px;
    transition: opacity 0.6s ease-in-out;
    opacity: 1;
}

#message-input::placeholder {
    color: #838383;
}

#message-input.hiding-placeholder {
    opacity: 0;
}

.input-actions {
    display: flex;
    align-items: flex-end;
    gap: 8px;
}

.attach-btn,
.send-btn {
    background-color: #ccc;
    border: none;
    border-radius: 50%;
    width: 36px;
    height: 36px;
    display: flex;
    justify-content: center;
    align-items: center;
    font-size: 16px;
    cursor: pointer;
    transition: 0.2s ease;
    flex-shrink: 0;
}

.attach-btn {
    background-color: transparent;
    color: var(--text-light);
}

.attach-btn:hover {
    background-color: var(--hover-bg);
    color: var(--text-color);
}

.send-btn {
    background-color: white;
    color: #333;
}

.send-btn:disabled {
    opacity: 0.5;
    cursor: not-allowed;
    box-shadow: none;
    background-color: #777;
}

.send-btn:not(:disabled):hover {
    background-color: rgba(255, 255, 255, 0.9);
    transform: translateY(-1px);
    box-shadow: 0 3px 6px rgba(0, 0, 0, 0.3);
}

.send-btn:not(:disabled):active {
    transform: translateY(0);
    box-shadow: 0 1px 2px rgba(0, 0, 0, 0.3);
}

/* --- Modals & Overlays --- */
.modal-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.7);
    display: none;
    justify-content: center;
    align-items: center;
    z-index: 1000;
    opacity: 0;
    transition: opacity 0.3s ease;
}

.modal-overlay.active {
    display: flex;
    opacity: 1;
}

.modal {
    background-color: #2c2c2e;
    color: #e0e0e0;
    padding: 25px 30px;
    border-radius: 10px;
    box-shadow: 0 5px 20px rgba(0, 0, 0, 0.4);
    max-width: 450px;
    width: 90%;
    text-align: center;
    transform: scale(0.9);
    transition: transform 0.3s ease, opacity 0.3s ease;
}

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

.modal h2 {
    margin-top: 0;
    margin-bottom: 15px;
    color: #ffcc00;
    font-size: 1.4em;
}

.modal h2 i {
    margin-right: 10px;
}

.modal p {
    margin-bottom: 10px;
    line-height: 1.5;
}

.modal p strong {
    color: #ffffff;
}

.modal .warning-text {
    font-weight: bold;
    color: #ff6b6b;
    margin-bottom: 25px;
    font-size: 0.9em;
}

.modal-actions {
    display: flex;
    justify-content: flex-end;
    gap: 15px;
    margin-top: 20px;
}

#delete-confirm-modal .modal-actions {
    justify-content: space-around;
}

.modal .btn {
    padding: 10px 20px;
    border: none;
    border-radius: 5px;
    cursor: pointer;
    font-size: 0.95em;
    font-weight: bold;
    display: inline-flex;
    align-items: center;
    gap: 8px;
    transition: background-color 0.2s ease, transform 0.1s ease;
}

.modal .btn:hover {
    opacity: 0.9;
    transform: translateY(-1px);
}

.modal .btn-primary {
    background-color: var(--accent-color);
    color: var(--bg-color);
}

.modal .btn-primary:hover {
    background-color: #e6e6e6;
}

.modal .btn-secondary {
    background-color: #555;
    color: white;
}

.modal .btn-secondary:hover {
    background-color: #666;
}

.modal .btn-danger {
    background-color: #e53935;
    color: white;
}

.modal .btn-danger:hover {
    background-color: #c62828;
}

/* --- App Settings Modal --- */
#app-settings-modal {
    max-width: 600px;
}

.app-settings-content {
    text-align: left;
    margin-bottom: 20px;
}

.app-settings-content .setting-item {
    margin-bottom: 15px;
}

.app-settings-content .setting-item label {
    display: block;
    font-weight: 500;
    margin-bottom: 5px;
}

.app-settings-content select,
.app-settings-content input[type="text"],
.app-settings-content input[type="password"],
.app-settings-content input[type="number"],
.app-settings-content textarea {
    background-color: var(--input-bg);
    border: 1px solid var(--border-color);
    color: var(--text-color);
    padding: 8px 12px;
    border-radius: 4px;
    outline: none;
    font-size: 0.9rem;
    width: 100%;
    box-sizing: border-box;
}

.app-settings-content textarea {
    min-height: 150px;
    resize: vertical;
    font-family: inherit;
}

.app-settings-content input[type="number"] {
    width: auto;
    min-width: 80px;
    flex-grow: 0;
}

.app-settings-content .setting-item-inline {
    display: flex;
    align-items: center;
    gap: 10px;
}

.app-settings-content .setting-item-inline label {
    margin-bottom: 0;
    flex-shrink: 0;
}

.api-key-input-container {
    position: relative;
    display: flex;
    align-items: center;
}

#gemini-api-key-input {
    padding-right: 40px;
}

#gemini-api-key-display {
    display: none;
    background-color: var(--input-bg);
    border: 1px solid var(--border-color);
    color: var(--text-color);
    padding: 8px 12px;
    border-radius: 4px;
    font-size: 0.9rem;
    width: 100%;
    box-sizing: border-box;
    font-family: monospace;
    letter-spacing: 1px;
    padding-right: 40px;
}

#api-key-toggle-btn {
    position: absolute;
    right: 1px;
    top: 1px;
    bottom: 1px;
    background: transparent;
    border: none;
    color: var(--text-light);
    cursor: pointer;
    padding: 0 12px;
    font-size: 1rem;
    outline: none;
}

#api-key-toggle-btn:hover {
    color: var(--text-color);
}

.api-key-helper-text {
    display: block;
    margin-top: 6px;
    font-size: 0.8rem;
    color: var(--text-light);
}

.api-key-helper-text a {
    color: var(--accent-color);
    text-decoration: none;
}

.api-key-helper-text a:hover {
    text-decoration: underline;
}

#system-prompt-input {
    resize: none;
    overflow-y: scroll !important;
}

#system-prompt-input::-webkit-scrollbar {
    width: 8px;
}

#system-prompt-input::-webkit-scrollbar-track {
    background: rgba(0, 0, 0, 0.2);
    border-radius: 4px;
}

#system-prompt-input::-webkit-scrollbar-thumb {
    background-color: rgba(255, 255, 255, 0.3);
    border-radius: 4px;
}

#system-prompt-input::-webkit-scrollbar-thumb:hover {
    background-color: rgba(255, 255, 255, 0.5);
}

/* --- Image Preview & Thumbnails --- */
.message-content .message-image-container {
    position: relative;
    width: 250px;
    height: 250px;
    border-radius: 12px;
    overflow: hidden;
    cursor: pointer;
    margin-top: 8px;
    border: 1px solid var(--border-color);
    background-color: var(--input-bg);
    transition: transform 0.25s cubic-bezier(0.25, 0.8, 0.25, 1), box-shadow 0.25s cubic-bezier(0.25, 0.8, 0.25, 1);
}

.message-content .message-image-container:hover {
    transform: scale(1.03);
    box-shadow: 0 6px 20px rgba(0, 0, 0, 0.2);
}

.message-content .message-image-thumbnail {
    width: 100%;
    height: 100%;
    object-fit: cover;
    display: block;
}

.image-preview-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.85);
    display: flex;
    justify-content: center;
    align-items: center;
    z-index: 10000;
    opacity: 0;
    visibility: hidden;
    backdrop-filter: blur(8px);
    transition: opacity 0.3s ease, visibility 0.3s ease;
}

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

.image-preview-overlay .image-preview-container {
    position: relative;
    display: flex;
    justify-content: center;
    align-items: center;
    transform: scale(0.9);
    transition: transform 0.3s cubic-bezier(0.175, 0.885, 0.32, 1.275);
}

.image-preview-overlay.active .image-preview-container {
    transform: scale(1);
}

.image-preview-overlay .image-preview-container::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-image: var(--bg-image);
    background-size: cover;
    background-position: center;
    transform: scale(1.1);
    filter: blur(30px) saturate(1.5);
    opacity: 0.7;
    z-index: -1;
}

.image-preview-image {
    max-width: 90vw;
    max-height: 85vh;
    border-radius: 8px;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.5);
    border: 1px solid rgba(255, 255, 255, 0.1);
    z-index: 1;
}

.image-preview-close-btn {
    position: absolute;
    top: -15px;
    right: -15px;
    width: 35px;
    height: 35px;
    background: var(--bg-color);
    color: var(--text-color);
    border: 1px solid var(--border-color);
    border-radius: 50%;
    font-size: 18px;
    font-weight: bold;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all 0.3s ease;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.3);
    line-height: 1;
    z-index: 2;
}

.image-preview-close-btn:hover {
    background: var(--accent-color);
    color: var(--bg-color);
    transform: rotate(180deg) scale(1.1);
}

/* --- Search --- */
.search-container {
    position: absolute;
    top: 14px;
    right: 10px;
    display: flex;
    align-items: center;
    height: 45px;
}

.search-btn {
    background: var(--input-bg);
    border: 1px solid var(--border-color);
    color: var(--text-light);
    cursor: pointer;
    padding: 8px;
    border-radius: 6px;
    transition: all 0.2s;
    opacity: 0.7;
    display: flex;
    align-items: center;
    justify-content: center;
    width: 45px;
    height: 100%;
}

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

.search-btn i {
    font-size: 14px;
}

.search-match-highlight {
    background-color: rgba(0, 255, 0, 0.2);
    border-radius: 2px;
    padding: 0 2px;
    transition: background-color 0.5s ease-out;
}

.search-match-highlight.fade {
    background-color: transparent;
}

.search-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.7);
    display: none;
    z-index: 1000;
}

.search-overlay.active {
    display: flex;
    align-items: flex-start;
    justify-content: center;
}

.search-modal {
    background: #202123;
    width: 90%;
    max-width: 600px;
    margin-top: 80px;
    border-radius: 8px;
    box-shadow: 0 8px 24px rgba(0, 0, 0, 0.2);
    overflow: hidden;
}

.search-header {
    padding: 8px;
    border-bottom: 1px solid #4d4d4f;
    display: flex;
    align-items: center;
    gap: 8px;
}

.search-input-container {
    flex: 1;
    display: flex;
    align-items: center;
    background: #40414f;
    border-radius: 6px;
    padding: 6px 12px;
    gap: 8px;
}

.search-input-container i {
    color: #8e8ea0;
}

#search-input {
    flex: 1;
    background: none;
    border: none;
    color: #fff;
    font-size: 14px;
    padding: 4px;
    outline: none;
}

.clear-search-btn,
.close-search-btn {
    background: none;
    border: none;
    color: #8e8ea0;
    cursor: pointer;
    padding: 6px;
    border-radius: 4px;
    transition: all 0.2s;
}

.clear-search-btn:hover,
.close-search-btn:hover {
    background: rgba(255, 255, 255, 0.1);
    color: #fff;
}

.search-results {
    max-height: 70vh;
    overflow-y: auto;
    padding: 8px;
}

.search-section {
    margin-bottom: 20px;
}

.search-section-header {
    font-size: 0.9em;
    color: #8e8ea0;
    text-transform: uppercase;
    margin: 8px 12px;
    font-weight: 500;
}

.search-result-item {
    display: flex;
    align-items: center;
    padding: 12px;
    cursor: pointer;
    border-radius: 8px;
    margin: 4px 0;
    transition: background-color 0.2s;
}

.search-result-item:hover {
    background-color: rgba(255, 255, 255, 0.1);
}

.search-result-item i {
    font-size: 20px;
    margin-right: 12px;
    color: #8e8ea0;
}

.search-result-content {
    flex: 1;
    overflow: hidden;
}

.search-result-title {
    font-weight: 500;
    margin-bottom: 4px;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.search-result-preview {
    font-size: 0.9em;
    color: #8e8ea0;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.search-highlight {
    background: rgba(255, 255, 255, 0.2);
    padding: 0 2px;
    border-radius: 2px;
}

/* --- Utility & State Classes --- */
.scroll-to-bottom-btn {
    position: fixed;
    bottom: 120px;
    right: 20px;
    background-color: var(--accent-color);
    color: black;
    width: 40px;
    height: 40px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    opacity: 0;
    transform: translateY(20px);
    transition: all 0.3s ease;
    z-index: 100;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.2);
}

.scroll-to-bottom-btn.visible {
    opacity: 1;
    transform: translateY(0);
}

.scroll-to-bottom-btn:hover {
    background-color: white;
    transform: translateY(-2px);
}

.connection-toast {
    position: fixed;
    top: 60px;
    left: 50%;
    transform: translateX(-50%);
    background: rgba(30, 30, 30, 0.92);
    color: #fff;
    padding: 14px 22px;
    font-size: 0.95em;
    font-weight: 500;
    z-index: 9999;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
    border-radius: 12px;
    box-shadow: 0 6px 18px rgba(0, 0, 0, 0.35);
    backdrop-filter: blur(6px);
    width: auto;
    min-width: 260px;
    max-width: 90%;
    transition: transform 0.4s ease, opacity 0.3s ease;
    opacity: 0;
}

.connection-toast:not(.hidden) {
    transform: translate(-50%, 0);
    opacity: 1;
}

.connection-toast.online {
    background: rgba(39, 174, 96, 0.92);
}

.connection-toast.offline {
    background: rgba(192, 57, 43, 0.92);
}

.copy-feedback {
    position: fixed;
    top: 20px;
    right: 20px;
    background: var(--accent-color);
    color: white;
    padding: 10px 20px;
    border-radius: 4px;
    opacity: 0;
    transform: translateY(-20px);
    transition: all 0.3s ease;
    pointer-events: none;
}

.copy-feedback.active {
    opacity: 1;
    transform: translateY(0);
}

.message-action-btn.copied {
    background-color: white;
    color: black;
    opacity: 1;
    animation: checkmark 0.3s ease-in-out;
}

.code-copy-button.copied i,
.message-action-btn.copied i {
    animation: checkmark 0.2s ease-in-out;
}

@keyframes checkmark {
    0% {
        transform: scale(0);
    }
    50% {
        transform: scale(1.2);
    }
    100% {
        transform: scale(1);
    }
}

/* --- Mobile Responsive Styles --- */
@media (max-width: 768px) {
    body,
    html {
        overflow: hidden !important;
    }

    .sidebar {
        left: -260px;
        transition: left 0.3s ease;
        z-index: 1000;
    }

    .sidebar.active {
        left: 0;
        box-shadow: 2px 0 5px rgba(0, 0, 0, 0.2);
    }

    .main-content {
        margin-left: 0;
        width: 100%;
        position: fixed !important;
        top: 0;
        left: 0;
        right: 0;
        bottom: 0;
        height: 100%;
        display: flex !important;
        flex-direction: column !important;
    }

    .top-bar,
    .bottom-bar {
        flex-shrink: 0;
        position: relative;
    }

    .chat-container {
        flex-grow: 1;
        overflow: hidden;
        min-height: 0;
    }

    .scroll-container {
        -webkit-overflow-scrolling: touch;
        position: absolute;
        top: 0;
        left: 0;
        right: 0;
        bottom: 0;
        overflow-y: auto;
    }

    .top-bar {
        padding: 8px 10px;
        gap: 6px;
    }

    .mobile-menu-btn,
    #app-settings-btn {
        display: block !important;
        font-size: 18px;
        padding: 8px;
    }

    .server-url-input {
        flex-grow: 1;
        min-width: 60px;
        font-size: 0.8rem;
        padding: 8px 10px;
    }

    .model-selector {
        flex-grow: 0.5;
        flex-shrink: 1;
        min-width: 100px;
        font-size: 0.8rem;
        padding: 8px 10px;
        padding-right: 28px;
        background-position: right 8px center;
    }

    .messages {
        max-width: 100%;
        padding: 0 8px;
    }

    .message {
        padding: 12px;
    }

    .bot-message .message-content,
    .user-message .message-content {
        font-size: 16px;
        line-height: 1.5;
    }

    .bot-message .message-content {
        padding: 0 12px;
        max-width: 100%;
        overflow-x: hidden;
        word-wrap: break-word;
    }
    
    .user-message {
        padding-right: 12px;
    }
    
    .message-timestamp {
        font-size: 13px;
    }

    .message-actions {
        top: -8px;
        right: 4px;
        opacity: 1 !important;
        visibility: visible !important;
    }
    
    .message-action-btn {
        padding: 4px;
        font-size: 12px;
    }

    .message-content pre {
        margin: 10px -8px;
        border-radius: 4px;
        max-width: calc(100vw - 32px);
        overflow-x: auto;
    }

    .message-content pre code {
        padding: 12px;
        font-size: 13px;
        white-space: pre-wrap;
    }

    .message-content img.user-uploaded-image,
    .message-content img {
        max-width: 100%;
        height: auto;
    }

    .message-content table {
        display: block;
        max-width: 100%;
        overflow-x: auto;
    }
    
    #typing-animation {
        padding: 12px 16px;
    }

    .typing-container {
        padding-left: 16px;
    }

    .bottom-bar {
        padding-bottom: calc(10px + env(safe-area-inset-bottom));
    }
    
    .input-area-container {
        margin: 0 8px;
        max-width: calc(100% - 16px);
    }

    #message-input {
        font-size: 16px;
        padding: 8px;
    }

    .overlay {
        display: none;
        position: fixed;
        top: 0;
        left: 0;
        right: 0;
        bottom: 0;
        background: rgba(0, 0, 0, 0.5);
        z-index: 999;
    }

    .overlay.active {
        display: block;
    }
    
    .connection-toast {
        top: 60px;
        font-size: 0.9em;
        padding: 12px 18px;
    }
}