/* ===== DreamPilot v2 - Main Styles ===== */

/* --- Theme Variables --- */
:root {
    --sidebar-width: 260px;
    --sidebar-collapsed-width: 0px;
    --primary: #4D6BFE;
    --primary-hover: #5E7AFF;
    --primary-light: rgba(77, 107, 254, 0.12);
    --danger: #ef4444;
    --success: #22c55e;
    --warning: #f59e0b;
    --radius: 12px;
    --radius-sm: 8px;
    --radius-lg: 16px;
    --radius-xl: 20px;
    --transition: 0.15s ease;
    --transition-slow: 0.25s ease;
    --font-sans: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', sans-serif;
    --font-mono: 'SF Mono', 'Fira Code', 'Consolas', monospace;
}

[data-theme="dark"] {
    --bg-primary: #141414;
    --bg-secondary: #1e1e1e;
    --bg-tertiary: #2a2a2a;
    --bg-hover: rgba(77, 107, 254, 0.08);
    --bg-input: #2a2a2a;
    --text-primary: #e0e0e0;
    --text-secondary: #a0a0a0;
    --text-muted: #666666;
    --border-color: rgba(255, 255, 255, 0.1);
    --code-bg: #2a2a2a;
}

[data-theme="light"] {
    --bg-primary: #ffffff;
    --bg-secondary: #f5f5f5;
    --bg-tertiary: #eeeeee;
    --bg-hover: rgba(77, 107, 254, 0.06);
    --bg-input: #f0f0f0;
    --text-primary: #1a1a1a;
    --text-secondary: #555555;
    --text-muted: #999999;
    --border-color: rgba(0, 0, 0, 0.1);
    --code-bg: #1e1e1e;
}

/* --- Reset --- */
*, *::before, *::after { margin: 0; padding: 0; box-sizing: border-box; }

html, body {
    height: 100%;
    font-family: var(--font-sans);
    overflow: hidden;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    background: var(--bg-primary);
    color: var(--text-primary);
}

::-webkit-scrollbar { width: 6px; height: 6px; }
::-webkit-scrollbar-track { background: transparent; }
[data-theme="dark"] ::-webkit-scrollbar-thumb { background: rgba(255,255,255,0.12); }
[data-theme="dark"] ::-webkit-scrollbar-thumb:hover { background: rgba(255,255,255,0.24); }
[data-theme="light"] ::-webkit-scrollbar-thumb { background: rgba(0,0,0,0.12); }
[data-theme="light"] ::-webkit-scrollbar-thumb:hover { background: rgba(0,0,0,0.24); }

/* --- App Container --- */
.app-container {
    display: flex;
    height: 100vh;
    height: 100dvh;
    width: 100vw;
    background: var(--bg-primary);
}

/* --- Sidebar --- */
.sidebar {
    width: var(--sidebar-width);
    min-width: var(--sidebar-width);
    display: flex;
    flex-direction: column;
    z-index: 100;
    overflow: hidden;
    transition: width var(--transition-slow), opacity var(--transition-slow), transform var(--transition-slow);
    background: var(--bg-secondary);
    border-right: 1px solid var(--border-color);
}
.sidebar.collapsed {
    width: var(--sidebar-collapsed-width);
    min-width: var(--sidebar-collapsed-width);
    opacity: 0;
    pointer-events: none;
}

.sidebar-top { padding: 12px 12px 0; }
.sidebar-header {
    display: flex;
    align-items: center;
    gap: 8px;
    margin-bottom: 8px;
}

.sidebar-toggle-btn {
    width: 36px; height: 36px;
    display: flex; align-items: center; justify-content: center;
    border: none; border-radius: var(--radius-sm);
    cursor: pointer;
    transition: background var(--transition);
    background: transparent;
    flex-shrink: 0;
    color: var(--text-secondary);
}
.sidebar-toggle-btn:hover { background: var(--bg-hover); }

.new-chat-btn {
    flex: 1;
    display: flex; align-items: center; justify-content: center;
    gap: 8px;
    padding: 10px 16px;
    border: 1px solid var(--border-color);
    border-radius: var(--radius);
    cursor: pointer;
    font-size: 14px;
    font-weight: 500;
    transition: background var(--transition), border-color var(--transition);
    background: transparent;
    color: var(--text-primary);
}
.new-chat-btn:hover { background: var(--bg-hover); border-color: var(--primary); }

.sidebar-search { position: relative; margin-bottom: 8px; }
.sidebar-search .search-icon {
    position: absolute;
    left: 10px;
    top: 50%;
    transform: translateY(-50%);
    opacity: 0.4;
    pointer-events: none;
    color: var(--text-secondary);
}
.sidebar-search input {
    width: 100%;
    padding: 8px 12px 8px 32px;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-sm);
    font-size: 13px;
    outline: none;
    transition: border-color var(--transition);
    background: transparent;
    color: var(--text-primary);
}
.sidebar-search input:focus { border-color: var(--primary); }
.sidebar-search input::placeholder { color: var(--text-muted); }

.conversation-list {
    flex: 1;
    overflow-y: auto;
    padding: 0 8px;
}

.conv-group-label {
    position: sticky;
    top: 0;
    z-index: 5;
    padding: 10px 12px 4px;
    font-size: 11px;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    backdrop-filter: blur(8px);
    -webkit-backdrop-filter: blur(8px);
    color: var(--text-muted);
    background: rgba(30,30,30,0.85);
}
[data-theme="light"] .conv-group-label { background: rgba(245,245,245,0.85); }

.conv-empty {
    text-align: center;
    padding: 40px 20px;
    opacity: 0.5;
    font-size: 13px;
    color: var(--text-secondary);
}

.conv-item {
    display: flex;
    align-items: center;
    padding: 10px 12px;
    border-radius: var(--radius-sm);
    cursor: pointer;
    font-size: 13px;
    transition: background var(--transition), transform var(--transition);
    position: relative;
    gap: 8px;
    transform: translateX(0);
    color: var(--text-primary);
}
.conv-item:hover { background: var(--bg-hover); transform: translateX(2px); }
.conv-item.active { background: var(--primary-light); }

.conv-item-icon {
    width: 28px; height: 28px;
    border-radius: 8px;
    display: flex; align-items: center; justify-content: center;
    flex-shrink: 0;
    background: var(--primary-light);
    color: var(--primary);
    font-size: 14px;
}
.conv-item-title {
    flex: 1;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
    min-width: 0;
}

.conv-generating-dot {
    width: 6px; height: 6px;
    border-radius: 50%;
    background: var(--primary);
    flex-shrink: 0;
    animation: conv-dot-pulse 1.2s ease-in-out infinite;
}
@keyframes conv-dot-pulse {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.3; }
}

.conv-item-actions { display: none; gap: 2px; }
.conv-item:hover .conv-item-actions { display: flex; }
.conv-item.active .conv-item-actions { display: flex; }
.conv-item-actions button {
    width: 26px; height: 26px;
    border: none; border-radius: 6px;
    cursor: pointer;
    display: flex; align-items: center; justify-content: center;
    background: transparent;
    opacity: 0.5;
    transition: opacity var(--transition), background var(--transition);
    color: var(--text-secondary);
}
.conv-item-actions button:hover { opacity: 1; background: var(--bg-hover); }

.sidebar-footer {
    display: flex;
    align-items: center;
    padding: 12px;
    gap: 4px;
    border-top: 1px solid var(--border-color);
}

.user-info {
    flex: 1;
    display: flex;
    align-items: center;
    gap: 8px;
    min-width: 0;
}

.user-avatar {
    width: 32px; height: 32px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 14px;
    font-weight: 600;
    flex-shrink: 0;
    background: var(--primary-light);
    color: var(--primary);
}

.user-name {
    font-size: 13px;
    font-weight: 500;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
    color: var(--text-primary);
}

.icon-btn {
    width: 36px; height: 36px;
    border: none; border-radius: var(--radius-sm);
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: opacity var(--transition), background var(--transition);
    background: transparent;
    opacity: 0.6;
    color: var(--text-secondary);
    flex-shrink: 0;
}
.icon-btn:hover { opacity: 1; background: var(--bg-hover); }

.sidebar-overlay {
    display: none;
    position: fixed;
    inset: 0;
    background: rgba(0,0,0,0.4);
    z-index: 99;
}
.sidebar-overlay.open { display: block; }

/* --- Main Content --- */
.main-content {
    flex: 1;
    display: flex;
    flex-direction: column;
    min-width: 0;
    min-height: 0;
    overflow: hidden;
    position: relative;
    background: var(--bg-primary);
}

.main-header {
    display: flex;
    align-items: center;
    padding: 8px 16px;
    gap: 8px;
    min-height: 48px;
    position: relative;
    z-index: 10;
    border-bottom: 1px solid var(--border-color);
    background: var(--bg-primary);
}

.mobile-menu-btn { display: none; }
.desktop-sidebar-toggle { display: none; }
.sidebar.collapsed ~ .main-content .desktop-sidebar-toggle { display: flex !important; }
.sidebar.collapsed ~ .main-content .mobile-menu-btn { display: none !important; }

.header-center {
    flex: 1;
    display: flex;
    align-items: center;
    justify-content: center;
}

.model-selector { position: relative; }

.model-selector-btn {
    display: flex;
    align-items: center;
    gap: 6px;
    padding: 6px 14px;
    border: 1px solid var(--border-color);
    border-radius: 20px;
    cursor: pointer;
    font-size: 14px;
    font-weight: 500;
    transition: background var(--transition), border-color var(--transition);
    background: transparent;
    color: var(--text-primary);
}
.model-selector-btn:hover { background: var(--bg-hover); border-color: var(--primary); }

.model-mode-indicator {
    font-size: 10px;
    padding: 1px 5px;
    border-radius: 4px;
    background: var(--primary);
    color: #fff;
    margin-right: 4px;
    font-weight: 600;
    line-height: 16px;
}
.model-name { font-size: 14px; font-weight: 500; }

.model-dropdown {
    position: absolute;
    top: calc(100% + 8px);
    left: 50%;
    transform: translateX(-50%);
    min-width: 260px;
    border-radius: var(--radius);
    padding: 6px;
    box-shadow: 0 8px 32px rgba(0,0,0,0.2);
    z-index: 200;
    display: none;
    background: var(--bg-secondary);
    border: 1px solid var(--border-color);
}
.model-dropdown.open { display: block; }

.model-group-label {
    padding: 8px 12px 4px;
    font-size: 11px;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    opacity: 0.5;
    color: var(--text-muted);
}

.model-option {
    display: flex;
    align-items: center;
    padding: 10px 12px;
    border-radius: var(--radius-sm);
    cursor: pointer;
    transition: background var(--transition);
    color: var(--text-primary);
}
.model-option:hover { background: var(--bg-hover); }
.model-option.active { background: var(--primary-light); }

.model-option-info { display: flex; flex-direction: column; gap: 2px; }
.model-option-name { font-size: 14px; font-weight: 500; }

.model-option-badge {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 32px;
    height: 24px;
    border-radius: 4px;
    font-size: 11px;
    font-weight: 700;
    flex-shrink: 0;
    background: var(--bg-hover);
    color: var(--text-secondary);
    margin-right: 8px;
}
.model-option-desc { font-size: 12px; opacity: 0.6; color: var(--text-secondary); }

.model-mode-tabs {
    display: flex;
    padding: 6px;
    gap: 4px;
    border-bottom: 1px solid var(--border-color);
}

.mode-tab {
    flex: 1;
    padding: 5px 12px;
    border: 1px solid transparent;
    border-radius: var(--radius-sm);
    background: transparent;
    cursor: pointer;
    font-size: 12px;
    font-weight: 500;
    transition: background var(--transition), color var(--transition), border-color var(--transition);
    color: var(--text-secondary);
}
.mode-tab:hover { background: var(--bg-hover); }
.mode-tab.active {
    background: var(--primary-light);
    color: var(--primary);
    border-color: var(--primary);
}

.model-dropdown-search {
    padding: 8px 12px;
    border-bottom: 1px solid var(--border-color);
}
.model-dropdown-search input {
    width: 100%;
    padding: 6px 12px;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-sm);
    font-size: 13px;
    background: transparent;
    outline: none;
    color: var(--text-primary);
}
.model-dropdown-search input:focus { border-color: var(--primary); }
.model-dropdown-content { max-height: 340px; overflow-y: auto; }

.header-actions { display: flex; gap: 2px; }

/* --- Chat Area --- */
.chat-area {
    flex: 1;
    min-height: 0;
    overflow-y: auto;
    display: flex;
    flex-direction: column;
    scroll-behavior: smooth;
    background: var(--bg-primary);
}

.welcome-screen {
    flex: 1;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 40px 20px;
}
.welcome-content { max-width: 640px; width: 100%; text-align: center; }
.welcome-logo { margin-bottom: 48px; }

.welcome-logo-icon {
    width: 64px; height: 64px;
    margin: 0 auto 20px;
    border-radius: 18px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--primary-light);
    color: var(--primary);
}
.welcome-logo h1 { font-size: 28px; font-weight: 700; margin-bottom: 8px; letter-spacing: -0.5px; }
.welcome-logo p { font-size: 15px; opacity: 0.5; color: var(--text-secondary); }

.quick-actions {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 10px;
    max-width: 520px;
    margin: 0 auto;
}

.quick-action-card {
    display: flex;
    flex-direction: column;
    align-items: flex-start;
    gap: 4px;
    padding: 16px;
    border: 1px solid var(--border-color);
    border-radius: var(--radius);
    cursor: pointer;
    transition: border-color var(--transition), background var(--transition), transform var(--transition), box-shadow var(--transition);
    background: transparent;
    text-align: left;
    color: var(--text-primary);
}
.quick-action-card:hover {
    border-color: var(--primary);
    background: var(--primary-light);
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(0,0,0,0.08);
}
.qa-icon { font-size: 22px; margin-bottom: 4px; }
.qa-text { font-size: 14px; font-weight: 600; }
.qa-desc { font-size: 12px; opacity: 0.5; color: var(--text-secondary); }

.messages-container {
    max-width: 800px;
    width: 100%;
    margin: 0 auto;
    padding: 20px 24px;
    background: var(--bg-primary);
}

.message { margin-bottom: 28px; }

.message-user {
    display: flex;
    justify-content: flex-end;
    flex-direction: column;
    align-items: flex-end;
}
.message-user .message-bubble {
    max-width: 70%;
    padding: 10px 16px;
    border-radius: 18px 18px 4px 18px;
    font-size: 14px;
    line-height: 1.6;
    word-break: break-word;
    background: linear-gradient(135deg, var(--primary), #5E7AFF);
    color: #fff;
    box-shadow: 0 2px 8px rgba(77, 107, 254, 0.25);
}

.message-assistant {
    display: flex;
    gap: 0;
    align-items: flex-start;
    flex-direction: column;
}
.message-assistant .message-content {
    flex: 1;
    min-width: 0;
    font-size: 15px;
    line-height: 1.75;
    word-break: break-word;
    overflow-wrap: break-word;
    white-space: normal;
}
.message-assistant .message-content .msg-text {
    width: 100%;
    overflow-wrap: break-word;
    white-space: normal;
}
.message-assistant .message-content .msg-text p {
    overflow-wrap: break-word;
    white-space: normal;
}
.message-assistant .message-content p { margin-bottom: 10px; }
.message-assistant .message-content p:last-child { margin-bottom: 0; }
.message-assistant .message-content ul, .message-assistant .message-content ol { padding-left: 20px; margin-bottom: 10px; }
.message-assistant .message-content li { margin-bottom: 4px; }
.message-assistant .message-content blockquote { border-left: 3px solid var(--primary); padding-left: 14px; margin: 10px 0; opacity: 0.8; }
.message-assistant .message-content table { border-collapse: collapse; margin: 10px 0; width: 100%; }
.message-assistant .message-content th, .message-assistant .message-content td { border: 1px solid var(--border-color); padding: 8px 14px; font-size: 13px; }
.message-assistant .message-content th { font-weight: 600; }
.message-assistant .message-content a { color: var(--primary); }
.message-assistant .message-content a:hover { text-decoration: underline; }

.message-assistant .message-content pre {
    margin: 12px 0;
    border-radius: var(--radius);
    overflow: hidden;
    background: var(--code-bg);
    border: 1px solid var(--border-color);
}
.message-assistant .message-content pre code {
    display: block;
    padding: 16px;
    font-size: 13px;
    line-height: 1.5;
    overflow-x: auto;
    white-space: pre-wrap;
    word-break: break-word;
    word-wrap: break-word;
    font-family: var(--font-mono);
}
.message-assistant .message-content :not(pre) > code {
    padding: 2px 6px;
    border-radius: 4px;
    font-size: 13px;
    font-family: var(--font-mono);
    background: var(--code-bg);
    color: var(--primary);
}

.code-block-wrapper {
    position: relative;
    margin: 12px 0;
    border-radius: var(--radius);
    overflow: hidden;
    border: 1px solid var(--border-color);
}
.code-block-wrapper pre {
    overflow-x: auto;
    white-space: pre-wrap;
    word-break: break-word;
    word-wrap: break-word;
}
.code-block-wrapper pre code {
    white-space: pre-wrap;
    word-break: break-word;
    word-wrap: break-word;
}
.code-block-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 8px 16px;
    font-size: 12px;
    background: var(--bg-tertiary);
    color: var(--text-secondary);
}
.code-block-copy {
    background: none;
    border: none;
    cursor: pointer;
    font-size: 12px;
    padding: 2px 10px;
    border-radius: 4px;
    transition: opacity var(--transition), background var(--transition);
    opacity: 0.6;
    color: var(--text-secondary);
}
.code-block-copy:hover { opacity: 1; background: var(--bg-hover); }

/* === Mode Badge ========== */
.message-mode-badge {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 1px 8px;
    border-radius: 4px;
    font-size: 11px;
    font-weight: 700;
    letter-spacing: 0.3px;
    background: var(--primary);
    color: #fff;
    margin-bottom: 8px;
    width: fit-content;
}

.typing-indicator {
    display: flex;
    gap: 4px;
    padding: 8px 0;
    align-items: center;
}
.typing-indicator span {
    width: 6px; height: 6px;
    border-radius: 50%;
    background: var(--text-muted);
    animation: typingBounce 1.4s ease-in-out infinite;
}
.typing-indicator span:nth-child(2) { animation-delay: 0.2s; }
.typing-indicator span:nth-child(3) { animation-delay: 0.4s; }
@keyframes typingBounce {
    0%, 60%, 100% { transform: translateY(0); }
    30% { transform: translateY(-6px); }
}

/* --- Message Actions --- */
.message-actions {
    display: flex;
    align-items: center;
    gap: 2px;
    opacity: 0;
    transition: opacity var(--transition);
    margin-top: 6px;
    padding: 0 2px;
}
.message:hover .message-actions,
.message-user:hover .message-actions { opacity: 1; }

.msg-action-btn {
    width: 30px; height: 30px;
    border: none; border-radius: 6px;
    cursor: pointer;
    display: flex; align-items: center; justify-content: center;
    transition: background var(--transition), color var(--transition), transform var(--transition);
    background: transparent;
    color: var(--text-muted);
    padding: 0;
}
.msg-action-btn:hover { background: var(--bg-hover); color: var(--text-primary); transform: scale(1.1); }
.msg-action-btn.feedback-btn.active { color: var(--primary); }
.msg-action-btn.feedback-btn.active[data-feedback-type="dislike"] { color: var(--danger); }
.msg-action-btn.msg-action-delete:hover { background: rgba(239,68,68,0.12); color: #ef4444; }

.fork-switcher {
    display: inline-flex;
    align-items: center;
    gap: 4px;
    margin-left: 4px;
}
.fork-nav-btn {
    width: 24px; height: 24px;
    border: 1px solid var(--border-color);
    border-radius: 6px;
    cursor: pointer;
    display: flex; align-items: center; justify-content: center;
    transition: border-color var(--transition), color var(--transition);
    background: transparent;
    color: var(--text-muted);
    padding: 0;
}
.fork-nav-btn:hover:not(:disabled) { border-color: var(--primary); color: var(--primary); }
.fork-nav-btn:disabled { opacity: 0.3; cursor: not-allowed; }
.fork-indicator {
    font-size: 12px;
    color: var(--text-muted);
    padding: 0 4px;
    min-width: 32px;
    text-align: center;
}

/* --- Thinking Block --- */
.thinking-block {
    margin-bottom: 12px;
    border-radius: var(--radius);
    overflow: hidden;
    border: 1px solid var(--border-color);
    background: var(--bg-secondary);
}
.thinking-header {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 10px 14px;
    cursor: pointer;
    font-size: 13px;
    transition: opacity var(--transition);
    user-select: none;
    color: var(--text-secondary);
}
.thinking-header:hover { opacity: 0.8; }
.thinking-toggle { transition: transform 0.3s cubic-bezier(0.2, 0.9, 0.4, 1.1); }
.thinking-toggle.expanded { transform: rotate(90deg); }

.thinking-content {
    padding: 0 14px;
    font-size: 13px;
    line-height: 1.6;
    max-height: 0;
    overflow: hidden;
    opacity: 0;
    transition: max-height 0.4s cubic-bezier(0.2, 0.9, 0.4, 1.1),
                opacity 0.3s var(--transition),
                padding 0.3s var(--transition);
    color: var(--text-secondary);
}
.thinking-content.expanded { padding: 12px 14px; max-height: 3000px; opacity: 1; }

.thinking-progress {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 10px 14px;
    font-size: 13px;
    color: var(--text-secondary);
}
.thinking-progress-bar {
    flex: 1;
    height: 3px;
    border-radius: 2px;
    overflow: hidden;
    background: rgba(255,255,255,0.08);
}
[data-theme="light"] .thinking-progress-bar { background: rgba(0,0,0,0.08); }
.thinking-progress-bar-inner {
    height: 100%;
    width: 30%;
    background: var(--primary);
    border-radius: 2px;
    animation: thinkingProgress 2s ease-in-out infinite;
}
@keyframes thinkingProgress {
    0% { transform: translateX(-100%); }
    100% { transform: translateX(400%); }
}

/* --- Search Results --- */
.search-results-block { margin-bottom: 12px; border-radius: var(--radius); overflow: hidden; border: 1px solid var(--border-color); background: var(--bg-secondary); }
.search-results-header {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 10px 14px;
    cursor: pointer;
    font-size: 13px;
    user-select: none;
    color: var(--text-secondary);
}
.search-results-content { padding: 8px 14px; display: none; }
.search-results-content.expanded { display: block; }

.search-result-item {
    display: flex;
    gap: 8px;
    padding: 8px 0;
    border-bottom: 1px solid rgba(255,255,255,0.05);
    font-size: 13px;
}
[data-theme="light"] .search-result-item { border-bottom: 1px solid rgba(0,0,0,0.05); }
.search-result-item:last-child { border-bottom: none; }
.search-result-index { color: var(--primary); font-weight: 600; flex-shrink: 0; }
.search-result-title { font-weight: 500; }
.search-result-snippet { opacity: 0.7; margin-top: 2px; color: var(--text-secondary); }
.search-result-url { color: var(--primary); font-size: 12px; margin-top: 2px; }

/* --- Input Area --- */
.input-area {
    padding: 0 16px 12px;
    max-width: 800px;
    width: 100%;
    margin: 0 auto;
    flex-shrink: 0;
}

.input-container {
    border: 1px solid var(--border-color);
    border-radius: var(--radius-xl);
    padding: 0;
    transition: border-color var(--transition), outline var(--transition);
    overflow: hidden;
    background: var(--bg-primary);
}
.input-container:focus-within {
    border-color: var(--primary);
    outline: 2px solid rgba(77, 107, 254, 0.15);
    outline-offset: -2px;
}

.file-preview { padding: 8px 16px 0; }
.file-preview-item {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 4px 12px;
    border-radius: 20px;
    font-size: 12px;
    background: var(--bg-tertiary);
    color: var(--text-secondary);
    border: 1px solid var(--border-color);
}
.file-preview-remove {
    background: none;
    border: none;
    cursor: pointer;
    font-size: 16px;
    opacity: 0.5;
    padding: 0 2px;
    transition: opacity var(--transition);
    color: var(--text-secondary);
}
.file-preview-remove:hover { opacity: 1; }

.input-wrapper {
    display: flex;
    align-items: flex-end;
    padding: 4px 8px 4px 16px;
    gap: 4px;
}
.input-wrapper textarea {
    flex: 1;
    border: none;
    outline: none;
    resize: none;
    font-size: 15px;
    line-height: 1.5;
    max-height: 200px;
    min-height: 24px;
    padding: 10px 0;
    background: transparent;
    font-family: var(--font-sans);
    color: var(--text-primary);
}
.input-wrapper textarea::placeholder { color: var(--text-muted); }

.input-actions {
    display: flex;
    align-items: center;
    gap: 4px;
    padding-bottom: 4px;
}

.send-btn, .stop-btn {
    width: 36px; height: 36px;
    border: none;
    border-radius: 50%;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: transform var(--transition), box-shadow var(--transition), opacity var(--transition);
    flex-shrink: 0;
}
.send-btn {
    background: linear-gradient(135deg, var(--primary), #5E7AFF);
    color: #fff;
    box-shadow: 0 2px 8px rgba(77, 107, 254, 0.3);
}
.send-btn:hover:not(:disabled) { transform: scale(1.06); box-shadow: 0 4px 16px rgba(77, 107, 254, 0.4); }
.send-btn:disabled { opacity: 0.3; cursor: not-allowed; transform: none; box-shadow: none; }
.stop-btn { background: var(--danger); color: #fff; display: none; }
.stop-btn:hover { opacity: 0.85; transform: scale(1.06); }

.input-toolbar {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 4px 12px 8px 16px;
}
.toolbar-left { display: flex; gap: 4px; flex-wrap: wrap; }
.toolbar-right { display: flex; align-items: center; }

.feature-toggle {
    display: flex;
    align-items: center;
    gap: 4px;
    padding: 4px 10px;
    border: 1px solid var(--border-color);
    border-radius: 16px;
    cursor: pointer;
    font-size: 12px;
    transition: background var(--transition), border-color var(--transition), color var(--transition);
    background: transparent;
    color: var(--text-secondary);
}
.feature-toggle:hover { border-color: var(--primary); background: var(--primary-light); }
.feature-toggle.active {
    background: var(--primary-light);
    border-color: var(--primary);
    color: var(--primary);
}
.feature-toggle.active svg { color: var(--primary); }

.token-counter { font-size: 11px; opacity: 0.4; color: var(--text-muted); }
.input-disclaimer { text-align: center; font-size: 11px; opacity: 0.3; margin-top: 6px; color: var(--text-muted); }

/* --- Modals --- */
#systemPromptModal,
#systemPromptModal .modal,
#settingsModal,
#settingsModal .modal-overlay,
#settingsModal .modal {
    animation: none !important;
}
.modal-overlay {
    position: fixed;
    inset: 0;
    background: rgba(0,0,0,0.5);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 500;
    animation: modalFadeIn 0.2s var(--transition);
}
@keyframes modalFadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

.modal {
    background: var(--bg-secondary);
    border-radius: var(--radius-lg);
    box-shadow: 0 8px 40px rgba(0,0,0,0.3);
    width: 480px;
    max-width: calc(100vw - 32px);
    max-height: calc(100vh - 32px);
    display: flex;
    flex-direction: column;
    animation: modalSlideIn 0.25s var(--transition);
    border: 1px solid var(--border-color);
}
@keyframes modalSlideIn {
    from { transform: translateY(16px) scale(0.97); opacity: 0; }
    to { transform: translateY(0) scale(1); opacity: 1; }
}

.modal.modal-large { width: 620px; }

.modal-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 20px 24px 16px;
    border-bottom: 1px solid var(--border-color);
}
.modal-header h3 { font-size: 18px; font-weight: 600; }

.modal-close {
    width: 32px; height: 32px;
    border: none; border-radius: var(--radius-sm);
    cursor: pointer;
    display: flex; align-items: center; justify-content: center;
    background: transparent;
    font-size: 20px;
    transition: background var(--transition);
    color: var(--text-secondary);
}
.modal-close:hover { background: var(--bg-hover); }

.modal-body { padding: 20px 24px; overflow-y: auto; flex: 1; }

.modal-footer {
    display: flex;
    justify-content: flex-end;
    gap: 8px;
    padding: 16px 24px 20px;
    border-top: 1px solid var(--border-color);
}

/* Settings Modal */
.settings-section { margin-bottom: 20px; }
.settings-section h4 { font-size: 12px; font-weight: 600; margin-bottom: 12px; text-transform: uppercase; letter-spacing: 0.5px; opacity: 0.5; color: var(--text-muted); }
.setting-item { margin-bottom: 12px; }
.setting-item label { display: block; font-size: 13px; margin-bottom: 6px; opacity: 0.7; color: var(--text-secondary); }
.setting-item input, .setting-item select, .setting-item textarea {
    width: 100%;
    padding: 8px 12px;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-sm);
    font-size: 14px;
    outline: none;
    transition: border-color var(--transition);
    background: transparent;
    font-family: var(--font-sans);
    color: var(--text-primary);
}
.setting-item input:focus, .setting-item select:focus, .setting-item textarea:focus { border-color: var(--primary); }
.setting-item textarea { resize: vertical; min-height: 60px; }

/* Buttons */
.btn-primary {
    padding: 8px 20px;
    background: var(--primary);
    color: #fff;
    border: none;
    border-radius: var(--radius-sm);
    cursor: pointer;
    font-size: 14px;
    font-weight: 500;
    transition: opacity var(--transition), transform var(--transition);
}
.btn-primary:hover { opacity: 0.9; transform: translateY(-1px); }
.btn-primary:disabled { opacity: 0.4; cursor: not-allowed; transform: none; }

.btn-secondary {
    padding: 8px 20px;
    background: transparent;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-sm);
    cursor: pointer;
    font-size: 14px;
    transition: background var(--transition), border-color var(--transition);
    color: var(--text-primary);
}
.btn-secondary:hover { background: var(--bg-hover); border-color: var(--primary); }

.btn-text {
    background: none;
    border: none;
    cursor: pointer;
    font-size: 13px;
    padding: 4px 8px;
    border-radius: var(--radius-sm);
    transition: background var(--transition), color var(--transition);
    color: var(--text-secondary);
}
.btn-text:hover { background: var(--bg-hover); color: var(--primary); }

/* System Prompt Presets */
.system-prompt-info {
    padding: 12px;
    border-radius: var(--radius-sm);
    margin-bottom: 16px;
    font-size: 13px;
    opacity: 0.6;
    background: var(--primary-light);
    color: var(--text-secondary);
}
.system-prompt-info p { margin: 0; }
.system-prompt-presets { margin-bottom: 12px; }
.system-prompt-presets label { display: block; font-size: 13px; margin-bottom: 8px; opacity: 0.7; }
.preset-buttons { display: flex; flex-wrap: wrap; gap: 8px; }

.preset-btn {
    padding: 6px 14px;
    border: 1px solid var(--border-color);
    border-radius: 20px;
    cursor: pointer;
    font-size: 12px;
    transition: background var(--transition), border-color var(--transition), color var(--transition);
    background: transparent;
    color: var(--text-secondary);
}
.preset-btn:hover { border-color: var(--primary); background: var(--primary-light); color: var(--primary); }

#systemPromptInput {
    width: 100%;
    padding: 10px 14px;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-sm);
    font-size: 14px;
    font-family: var(--font-sans);
    resize: vertical;
    margin-bottom: 8px;
    background: var(--bg-input);
    color: var(--text-primary);
    outline: none;
}
#systemPromptInput:focus { border-color: var(--primary); }

.system-prompt-actions { display: flex; gap: 8px; }

/* --- Context Menu --- */
.context-menu {
    position: fixed;
    z-index: 400;
    border-radius: var(--radius);
    padding: 4px;
    min-width: 160px;
    box-shadow: 0 4px 20px rgba(0,0,0,0.25);
    background: var(--bg-secondary);
    border: 1px solid var(--border-color);
}
.context-menu-item {
    display: flex;
    align-items: center;
    gap: 8px;
    width: 100%;
    padding: 8px 12px;
    border: none;
    border-radius: var(--radius-sm);
    cursor: pointer;
    font-size: 13px;
    transition: background var(--transition);
    background: transparent;
    text-align: left;
    color: var(--text-primary);
    font-family: var(--font-sans);
}
.context-menu-item:hover { background: var(--bg-hover); }
.context-menu-item.danger { color: var(--danger); }

/* --- Images --- */
.image-bubble { margin: 8px 0; }
.image-grid { display: grid; gap: 12px; margin: 12px 0; }
.image-grid.single { grid-template-columns: 1fr; max-width: 512px; }
.image-grid.multi { grid-template-columns: repeat(2, 1fr); }

.image-container {
    border-radius: var(--radius);
    overflow: hidden;
    cursor: pointer;
    transition: transform var(--transition), box-shadow var(--transition);
    position: relative;
    border: 1px solid var(--border-color);
}
.image-container:hover { transform: scale(1.03); box-shadow: 0 4px 20px rgba(0,0,0,0.2); }
.image-container img { width: 100%; height: auto; display: block; }

.image-actions {
    position: absolute;
    top: 8px;
    right: 8px;
    display: flex;
    gap: 4px;
    opacity: 0;
    transition: opacity var(--transition);
}
.image-container:hover .image-actions { opacity: 1; }

.image-action-btn {
    width: 32px; height: 32px;
    border: none;
    border-radius: 6px;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    background: rgba(0,0,0,0.6);
    color: #fff;
    transition: background var(--transition), transform var(--transition);
}
.image-action-btn:hover { background: rgba(0,0,0,0.85); transform: scale(1.1); }

.image-info { padding: 8px 0; font-size: 12px; opacity: 0.5; color: var(--text-secondary); }
.image-prompt-text { font-style: italic; }

.image-loading {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 12px;
    padding: 40px;
    border: 1px dashed var(--border-color);
    border-radius: var(--radius);
}
.image-loading-spinner {
    width: 32px; height: 32px;
    border: 3px solid var(--border-color);
    border-top-color: var(--primary);
    border-radius: 50%;
    animation: spin 0.8s linear infinite;
}
@keyframes spin { to { transform: rotate(360deg); } }
.image-loading-text { font-size: 14px; opacity: 0.6; color: var(--text-secondary); }

/* --- Image Lightbox --- */
.image-lightbox {
    position: fixed;
    inset: 0;
    background: rgba(0,0,0,0.9);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 600;
    opacity: 0;
    visibility: hidden;
    transition: opacity 0.25s var(--transition), visibility 0.25s var(--transition);
}
.image-lightbox.active { opacity: 1; visibility: visible; }

.image-lightbox-content {
    position: relative;
    max-width: 90vw;
    max-height: 90vh;
}
.image-lightbox-content img { max-width: 100%; max-height: 90vh; object-fit: contain; border-radius: 8px; }

.image-lightbox-close {
    position: fixed;
    top: 16px;
    right: 16px;
    width: 40px; height: 40px;
    border: none;
    border-radius: 50%;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    background: rgba(0,0,0,0.5);
    color: #fff;
    font-size: 24px;
    transition: background var(--transition), transform var(--transition);
    z-index: 601;
}
.image-lightbox-close:hover { background: rgba(255,255,255,0.2); transform: scale(1.1); }

.image-lightbox-actions {
    position: fixed;
    bottom: 24px;
    left: 50%;
    transform: translateX(-50%);
    display: flex;
    gap: 8px;
    padding: 8px 16px;
    border-radius: var(--radius);
    background: rgba(0,0,0,0.6);
}
.image-lightbox-actions button {
    padding: 8px 16px;
    border: none;
    border-radius: 6px;
    cursor: pointer;
    font-size: 13px;
    transition: background var(--transition);
    background: rgba(255,255,255,0.1);
    color: #fff;
}
.image-lightbox-actions button:hover { background: rgba(255,255,255,0.2); }

.image-lightbox-info {
    position: fixed;
    top: 16px;
    left: 50%;
    transform: translateX(-50%);
    padding: 8px 20px;
    border-radius: var(--radius);
    font-size: 13px;
    max-width: 80vw;
    text-align: center;
    background: rgba(0,0,0,0.7);
    color: #fff;
}

/* --- Message Edit --- */
.message-edit-container { max-width: 70%; width: 100%; margin-top: 4px; }
.message-edit-textarea {
    width: 100%;
    padding: 10px 14px;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-sm);
    font-size: 14px;
    font-family: var(--font-sans);
    resize: none;
    background: var(--bg-input);
    color: var(--text-primary);
    outline: none;
}
.message-edit-textarea:focus { outline: 2px solid rgba(77, 107, 254, 0.3); outline-offset: -2px; }
.message-edit-actions { display: flex; justify-content: flex-end; gap: 8px; margin-top: 8px; }

.edit-cancel-btn {
    padding: 6px 14px;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-sm);
    cursor: pointer;
    font-size: 13px;
    transition: background var(--transition);
    background: transparent;
    color: var(--text-primary);
}
.edit-cancel-btn:hover { background: var(--bg-hover); }

.edit-submit-btn {
    padding: 6px 14px;
    border: none;
    border-radius: var(--radius-sm);
    cursor: pointer;
    font-size: 13px;
    font-weight: 500;
    background: var(--primary);
    color: #fff;
    transition: opacity var(--transition);
}
.edit-submit-btn:hover { opacity: 0.9; }

/* --- Toast --- */
.toast-notification {
    position: fixed;
    bottom: 24px;
    left: 50%;
    transform: translateX(-50%) translateY(80px);
    padding: 10px 24px;
    border-radius: var(--radius);
    font-size: 14px;
    z-index: 700;
    opacity: 0;
    transition: transform 0.3s var(--transition), opacity 0.3s var(--transition);
    pointer-events: none;
    background: var(--bg-tertiary);
    color: var(--text-primary);
    border: 1px solid var(--border-color);
    box-shadow: 0 4px 16px rgba(0,0,0,0.15);
}
.toast-notification.toast-show { transform: translateX(-50%) translateY(0); opacity: 1; }

/* --- Login Page --- */
.login-page {
    min-height: 100vh;
    min-height: 100dvh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 20px;
    background: var(--bg-primary);
}
.login-page, .login-page * { box-sizing: border-box; }

.login-container {
    width: 380px;
    max-width: 100%;
}
.login-header {
    text-align: center;
    margin-bottom: 32px;
}
.login-logo { margin-bottom: 16px; display: flex; justify-content: center; }
.login-header h1 { font-size: 28px; font-weight: 700; letter-spacing: -0.5px; margin-bottom: 6px; }
.login-header p { font-size: 15px; opacity: 0.5; color: var(--text-secondary); }

.login-error {
    padding: 10px 14px;
    border-radius: var(--radius-sm);
    font-size: 13px;
    margin-bottom: 16px;
    background: rgba(239,68,68,0.1);
    color: var(--danger);
    border: 1px solid rgba(239,68,68,0.2);
}

.form-group { margin-bottom: 16px; }
.form-group label {
    display: block;
    font-size: 13px;
    font-weight: 500;
    margin-bottom: 6px;
    color: var(--text-secondary);
}
.form-group input {
    width: 100%;
    padding: 10px 14px;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-sm);
    font-size: 15px;
    outline: none;
    transition: border-color var(--transition);
    background: var(--bg-input);
    color: var(--text-primary);
}
.form-group input:focus { border-color: var(--primary); }
.form-group input::placeholder { color: var(--text-muted); }

.login-btn {
    width: 100%;
    padding: 12px;
    border: none;
    border-radius: var(--radius-sm);
    cursor: pointer;
    font-size: 15px;
    font-weight: 600;
    transition: opacity var(--transition), transform var(--transition);
    background: var(--primary);
    color: #fff;
}
.login-btn:hover { opacity: 0.9; transform: translateY(-1px); }
.login-btn:disabled { opacity: 0.5; cursor: not-allowed; transform: none; }

.register-link {
    text-align: center;
    margin-top: 24px;
    font-size: 14px;
    color: var(--text-secondary);
}
.register-link a { color: var(--primary); text-decoration: none; }
.register-link a:hover { text-decoration: underline; }
.login-notice {
    text-align: center;
    margin-top: 18px;
    font-size: 12px;
    color: var(--text-secondary);
    opacity: 0.45;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 6px;
}

/* --- Responsive --- */
@media (max-width: 768px) {
    .sidebar {
        position: fixed;
        top: 0;
        left: 0;
        bottom: 0;
        transform: translateX(-100%);
        z-index: 100;
        box-shadow: 4px 0 20px rgba(0,0,0,0.3);
        backdrop-filter: blur(12px);
        -webkit-backdrop-filter: blur(12px);
    }
    .sidebar.open {
        transform: translateX(0);
        width: var(--sidebar-width);
        min-width: var(--sidebar-width);
        opacity: 1;
        pointer-events: auto;
    }
    .sidebar.collapsed { transform: translateX(-100%); }
    .sidebar-overlay.open { display: block; }
    .mobile-menu-btn { display: flex; }
    .desktop-sidebar-toggle { display: none !important; }
    .sidebar-toggle-btn { display: none; }
    .input-area { padding: 0 8px 8px; }
    .quick-actions { grid-template-columns: 1fr; }
    .message-user .message-bubble { max-width: 85%; }
    .messages-container { padding: 12px; }
    .welcome-logo h1 { font-size: 22px; }
    .feature-toggle span { display: none; }
    .feature-toggle { padding: 8px; }
    .input-toolbar { padding: 4px 8px 6px 12px; }
    .message-edit-container { max-width: 85%; }
}

@media (max-width: 480px) {
    .main-header { padding: 6px 8px; }
    .header-actions .icon-btn { padding: 4px; }
    .model-selector-btn { padding: 4px 10px; font-size: 13px; }
}