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

html {
    scroll-behavior: smooth;
    text-size-adjust: 100%;
}

input, button, textarea, select {
    font: inherit;
    color: inherit;
    background: transparent;
    border: none;
    outline: none;
}

button {
    cursor: pointer;
    user-select: none;
}

img, picture, svg, video {
    display: block;
    max-width: 100%;
    height: auto;
}

ul, ol {
    list-style: none;
}

a {
    text-decoration: none;
    color: inherit;
}

.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border: 0;
}

:root {
    --bg-primary: #f9f9f6;
    --bg-secondary: #ffffff;
    --bg-chat: #f9f9f6;
    --bg-sidebar: #f3f3ee;
    --bg-input: #ffffff;
    --bg-header: rgba(249, 249, 246, 0.85);
    
    --text-primary: #1d1d1b;
    --text-secondary: #5c5c54;
    --text-muted: #595952;
    
    --accent-primary: #6c5ce7;
    --accent-secondary: #574bcf;
    --accent-glow: rgba(108, 92, 231, 0.15);
    
    --bubble-bot-bg: #ffffff;
    --bubble-bot-text: #1d1d1b;
    --bubble-bot-border: rgba(0, 0, 0, 0.06);
    --bubble-user-bg: #e4e4db;
    --bubble-user-text: #1d1d1b;
    --bubble-suggestion-bg: rgba(108, 92, 231, 0.05);
    --bubble-suggestion-border: rgba(108, 92, 231, 0.22);
    --bubble-suggestion-hover: rgba(108, 92, 231, 0.1);
    
    --border-color: rgba(0, 0, 0, 0.06);
    --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.03);
    --shadow-md: 0 4px 20px rgba(0, 0, 0, 0.05);
    --shadow-lg: 0 8px 32px rgba(0, 0, 0, 0.08);
    
    --nav-bg: rgba(255, 255, 255, 0.7);
    --nav-active: #6c5ce7;
    --nav-inactive: #5c5c54;
    
    --scrollbar-track: #f9f9f6;
    --scrollbar-thumb: #e2e2d9;
    
    --code-bg: #f3f3ee;
    --code-text: #574bcf;
    --project-bg: #ffffff;

    --font-primary: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    --font-mono: 'JetBrains Mono', 'Fira Code', monospace;
    
    --radius-sm: 6px;
    --radius-md: 10px;
    --radius-lg: 16px;
    --radius-full: 9999px;

    --spacing-sm: 8px;
    --spacing-md: 16px;
    --spacing-lg: 24px;
    --spacing-xl: 32px;
    
    --transition-fast: 0.12s ease;
    --transition-normal: 0.22s cubic-bezier(0.4, 0, 0.2, 1);
    --transition-slow: 0.35s cubic-bezier(0.16, 1, 0.3, 1);
    
    --sidebar-width: 260px;
    --header-height: 60px;
    --chat-max-width: 760px;
}

:root[data-theme="dark"] {
    --bg-primary: #0a0a0d;
    --bg-secondary: #14141a;
    --bg-chat: #0a0a0d;
    --bg-sidebar: #14141a;
    --bg-input: #14141a;
    --bg-header: rgba(10, 10, 13, 0.85);
    
    --text-primary: #e3e3e9;
    --text-secondary: #9a9ab0;
    --text-muted: #5c5c70;
    
    --accent-primary: #7d5fff;
    --accent-secondary: #9b82ff;
    --accent-glow: rgba(125, 95, 255, 0.25);
    
    --bubble-bot-bg: #14141a;
    --bubble-bot-text: #e3e3e9;
    --bubble-bot-border: rgba(255, 255, 255, 0.06);
    --bubble-user-bg: #7d5fff;
    --bubble-user-text: #ffffff;
    --bubble-suggestion-bg: rgba(125, 95, 255, 0.08);
    --bubble-suggestion-border: rgba(125, 95, 255, 0.3);
    --bubble-suggestion-hover: rgba(125, 95, 255, 0.18);
    
    --border-color: rgba(255, 255, 255, 0.08);
    --scrollbar-track: #0a0a0d;
    --scrollbar-thumb: #23232f;
    --code-bg: #050507;
    --code-text: #e8e7ff;
    --project-bg: #0a0a0d;
}

body {
    font-family: var(--font-primary);
    background-color: var(--bg-primary);
    color: var(--text-primary);
    min-height: 100dvh;
    text-rendering: optimizeSpeed;
    line-height: 1.5;
    overflow-x: hidden;
    transition: background-color var(--transition-normal), color var(--transition-normal);
}

@media (min-width: 768px) {
    body {
        overflow: hidden;
    }
}

body.reading-mode {
    overflow: auto !important;
}

*:focus-visible {
    outline: 2px solid var(--accent-primary);
    outline-offset: 2px;
    border-radius: 2px;
}

.theme-transitioning,
.theme-transitioning * {
    transition: background-color var(--transition-normal) !important, 
                color var(--transition-normal) !important, 
                border-color var(--transition-normal) !important,
                box-shadow var(--transition-normal) !important;
}

::-webkit-scrollbar {
    width: 6px;
    height: 6px;
}

::-webkit-scrollbar-track {
    background: var(--scrollbar-track);
}

::-webkit-scrollbar-thumb {
    background: var(--scrollbar-thumb);
    border-radius: var(--radius-sm);
}

::-webkit-scrollbar-thumb:hover {
    background: var(--accent-primary);
}

.app-container {
    display: flex;
    width: 100vw;
    height: 100dvh;
    overflow: hidden;
    position: relative;
}

.chat-sidebar {
    width: var(--sidebar-width);
    height: 100%;
    background-color: var(--bg-sidebar);
    border-right: 1px solid var(--border-color);
    display: flex;
    flex-direction: column;
    flex-shrink: 0;
    transition: transform var(--transition-slow), background-color var(--transition-normal), border-color var(--transition-normal);
    z-index: 500;
}

.sidebar-header {
    height: var(--header-height);
    padding: 0 16px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    border-bottom: 1px solid var(--border-color);
}

.brand {
    display: flex;
    align-items: center;
    gap: 10px;
    font-weight: 700;
    font-size: 18px;
    letter-spacing: -0.02em;
}

.brand-logo {
    font-size: 20px;
}

.new-chat-btn {
    width: 36px;
    height: 36px;
    border-radius: var(--radius-md);
    background-color: transparent;
    display: flex;
    align-items: center;
    justify-content: center;
    border: 1px solid var(--border-color);
    color: var(--text-secondary);
    transition: background-color var(--transition-fast), border-color var(--transition-fast);
}

.new-chat-btn:hover {
    background-color: var(--border-color);
    color: var(--text-primary);
}

.sidebar-nav {
    flex: 1;
    overflow-y: auto;
    padding: 20px 12px;
}

.nav-section-title {
    font-size: 11px;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--text-muted);
    margin-bottom: 8px;
    padding-left: 8px;
}

.nav-list {
    display: flex;
    flex-direction: column;
    gap: 4px;
}

.sidebar-nav-item {
    width: 100%;
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 10px 12px;
    border-radius: var(--radius-md);
    font-size: 14px;
    font-weight: 500;
    color: var(--text-secondary);
    transition: background-color var(--transition-fast), color var(--transition-fast);
    text-align: left;
}

.sidebar-nav-item:hover {
    background-color: var(--border-color);
    color: var(--text-primary);
}

.sidebar-nav-item.active {
    background-color: var(--border-color);
    color: var(--text-primary);
    font-weight: 600;
}

.sidebar-footer {
    padding: 16px 12px;
    border-top: 1px solid var(--border-color);
    display: flex;
    flex-direction: column;
    gap: 16px;
}

.footer-links {
    display: flex;
    flex-direction: column;
    gap: 6px;
    padding-left: 8px;
}

.footer-link-item {
    font-size: 12px;
    color: var(--text-muted);
    transition: color var(--transition-fast);
}

.footer-link-item:hover {
    color: var(--accent-primary);
}

.profile-block {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 8px;
    border-radius: var(--radius-md);
    background-color: var(--border-color);
}

.profile-avatar {
    width: 36px;
    height: 36px;
    border-radius: var(--radius-full);
    background-color: var(--accent-primary);
    color: #ffffff;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 600;
    font-size: 14px;
}

.profile-info {
    flex: 1;
    overflow: hidden;
}

.profile-name {
    font-size: 13.5px;
    font-weight: 600;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.profile-plan {
    font-size: 11px;
    color: var(--text-muted);
}

.theme-toggle-compact {
    width: 32px;
    height: 32px;
    border-radius: var(--radius-md);
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--text-secondary);
    transition: background-color var(--transition-fast), color var(--transition-fast);
}

.theme-toggle-compact:hover {
    background-color: var(--border-color);
    color: var(--text-primary);
}

.chat-main {
    flex: 1;
    display: flex;
    flex-direction: column;
    height: 100%;
    overflow: hidden;
    position: relative;
    background-color: var(--bg-chat);
    transition: background-color var(--transition-normal);
}

.chat-header {
    height: var(--header-height);
    background-color: var(--bg-header);
    border-bottom: 1px solid var(--border-color);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0 16px;
    position: sticky;
    top: 0;
    z-index: 100;
    transition: background-color var(--transition-normal), border-color var(--transition-normal);
}

.sidebar-toggle {
    width: 36px;
    height: 36px;
    border-radius: var(--radius-md);
    display: none;
    align-items: center;
    justify-content: center;
    color: var(--text-secondary);
    transition: background-color var(--transition-fast);
}

.sidebar-toggle:hover {
    background-color: var(--border-color);
}

.header-center {
    display: flex;
    flex-direction: column;
    align-items: center;
    text-align: center;
}

.header-name {
    font-weight: 600;
    font-size: 15px;
    letter-spacing: -0.01em;
}

.header-status {
    font-size: 11px;
    color: var(--text-secondary);
    display: flex;
    align-items: center;
    gap: 4px;
}

.status-dot {
    width: 6px;
    height: 6px;
    border-radius: var(--radius-full);
    background-color: #2ed573;
    box-shadow: 0 0 6px rgba(46, 213, 115, 0.4);
}

.header-right .theme-toggle {
    width: 36px;
    height: 36px;
    border-radius: var(--radius-md);
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--text-secondary);
    transition: background-color var(--transition-fast);
}

.header-right .theme-toggle:hover {
    background-color: var(--border-color);
}

.chat-input-area {
    background-color: var(--bg-chat);
    border-top: 1px solid var(--border-color);
    padding: 12px 16px 24px 16px;
    z-index: 10;
    transition: background-color var(--transition-normal), border-color var(--transition-normal);
}

.message-form {
    max-width: var(--chat-max-width);
    margin: 0 auto;
}

.input-wrapper {
    background-color: var(--bg-input);
    border: 1px solid var(--border-color);
    border-radius: 20px;
    display: flex;
    align-items: flex-end;
    padding: 6px 6px 6px 14px;
    box-shadow: var(--shadow-sm);
    transition: border-color var(--transition-fast), box-shadow var(--transition-fast), background-color var(--transition-normal);
}

.input-wrapper:focus-within {
    border-color: var(--accent-primary);
    box-shadow: 0 0 0 3px var(--accent-glow);
}

textarea {
    flex: 1;
    border: none;
    resize: none;
    background: transparent;
    padding: 8px 0;
    max-height: 120px;
    line-height: 1.5;
    font-size: 14.5px;
    color: var(--text-primary);
    overflow-y: auto;
}

textarea::placeholder {
    color: var(--text-muted);
}

.send-btn {
    width: 32px;
    height: 32px;
    border-radius: 12px;
    background-color: var(--accent-primary);
    color: #ffffff;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: background-color var(--transition-fast), transform var(--transition-fast), opacity var(--transition-fast);
    flex-shrink: 0;
}

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

.send-btn:active {
    transform: scale(0.95);
}

.send-btn:disabled {
    background-color: transparent;
    color: var(--text-muted);
    cursor: not-allowed;
    transform: none;
}

body.reading-mode .chat-sidebar {
    display: none !important;
}

body.reading-mode .chat-main {
    flex: none !important;
    width: 100%;
    max-width: 800px;
    margin: 0 auto;
    border-left: 1px solid var(--border-color);
    border-right: 1px solid var(--border-color);
}

body.reading-mode .app-container {
    justify-content: center;
    background-color: var(--bg-primary);
}

@keyframes fadeInUp {
    from { opacity: 0; transform: translateY(16px); }
    to { opacity: 1; transform: translateY(0); }
}

.message {
    animation: fadeInUp 0.35s cubic-bezier(0.16, 1, 0.3, 1) both;
}

@keyframes slideInRight {
    from { transform: translateX(100%); }
    to { transform: translateX(0); }
}

@keyframes slideOutRight {
    from { transform: translateX(0); }
    to { transform: translateX(100%); }
}

.project-panel {
    animation: slideInRight 0.4s cubic-bezier(0.16, 1, 0.3, 1) both;
}

.project-panel.closing {
    animation: slideOutRight 0.35s cubic-bezier(0.16, 1, 0.3, 1) both;
}

@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

@keyframes fadeOut {
    from { opacity: 1; }
    to { opacity: 0; }
}

.project-overlay {
    animation: fadeIn 0.3s ease both;
}

.project-overlay.closing {
    animation: fadeOut 0.25s ease both;
}

@keyframes typingDot {
    0%, 60%, 100% { transform: translateY(0); opacity: 0.3; }
    30% { transform: translateY(-5px); opacity: 1; }
}

.typing-dot {
    animation: typingDot 1.4s infinite ease-in-out;
}

.typing-dot:nth-child(1) { animation-delay: 150ms; }
.typing-dot:nth-child(2) { animation-delay: 300ms; }
.typing-dot:nth-child(3) { animation-delay: 450ms; }

@keyframes cursorBlink {
    50% { opacity: 0; }
}

.typing-cursor {
    display: inline-block;
    width: 2px;
    height: 15px;
    background-color: var(--accent-primary);
    margin-left: 2px;
    vertical-align: middle;
    animation: cursorBlink 0.8s infinite;
}

@media (max-width: 767px) {
    .chat-header {
        padding: 0 var(--spacing-md);
    }
    
    .chat-input-area {
        padding: 12px var(--spacing-md) 24px var(--spacing-md);
    }

    .chat-sidebar {
        position: absolute;
        left: 0;
        top: 0;
        bottom: 0;
        transform: translateX(-100%);
    }

    body.sidebar-open .chat-sidebar {
        transform: translateX(0);
    }
    
    body.sidebar-open::after {
        content: '';
        position: fixed;
        inset: 0;
        background-color: rgba(0,0,0,0.4);
        z-index: 450;
        backdrop-filter: blur(2px);
    }

    .sidebar-toggle {
        display: flex;
    }
}

@media (min-width: 768px) {
    .chat-header {
        padding: 0 24px;
    }
    
    .chat-input-area {
        padding: 16px 24px 32px 24px;
    }
}