:root {
    /* Theme Colors */
    --bg-primary: rgb(20, 19, 19);
    --bg-secondary: rgb(31, 29, 29);
    --text-primary: rgb(242, 237, 230);
    --text-secondary: rgb(204, 200, 194);
    --text-tertiary: rgb(102, 95, 86);
    --accent: rgb(242, 237, 230);
    
    /* Typography */
    --font-primary: 'Manrope', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    --font-mono: 'DM Mono', 'SF Mono', Monaco, 'Cascadia Code', monospace;
    
    /* Layout */
    --container-max: min(1200px, 95vw);
    --container-padding: clamp(1rem, 3vw, 2rem);
    
    /* Spacing System */
    --space-xs: clamp(0.25rem, 1vw, 0.5rem);
    --space-sm: clamp(0.5rem, 2vw, 1rem);
    --space-md: clamp(1rem, 3vw, 1.5rem);
    --space-lg: clamp(1.5rem, 4vw, 2.5rem);
    --space-xl: clamp(2rem, 5vw, 3.5rem);
    
    /* Typography Scale */
    --text-xs: clamp(0.75rem, 2vw, 0.875rem);
    --text-sm: clamp(0.875rem, 2.5vw, 1rem);
    --text-base: clamp(1rem, 3vw, 1.125rem);
    --text-lg: clamp(1.125rem, 3.5vw, 1.25rem);
    --text-xl: clamp(1.25rem, 4vw, 1.5rem);
    --text-2xl: clamp(1.5rem, 5vw, 2rem);
    --text-3xl: clamp(2rem, 6vw, 3rem);
    
    /* Design System */
    --radius-sm: 0.5rem;
    --radius-md: 0.75rem;
    --radius-lg: 1rem;
    --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.2);
    --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.3);
    --shadow-lg: 0 10px 25px rgba(0, 0, 0, 0.4);
    
    /* Transitions */
    --transition-fast: 150ms cubic-bezier(0.4, 0, 0.2, 1);
    --transition-base: 300ms cubic-bezier(0.4, 0, 0.2, 1);
    --transition-slow: 500ms cubic-bezier(0.4, 0, 0.2, 1);
    --transition-spring: 400ms cubic-bezier(0.34, 1.56, 0.64, 1);
}

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

html {
    font-size: 16px;
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-primary);
    background: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.7;
    overflow-x: hidden;
    min-height: 100vh;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

/* Main Layout */
.app-container {
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    position: relative;
}

.chat-wrapper {
    flex: 1;
    display: flex;
    flex-direction: column;
    max-width: var(--container-max);
    margin: 0 auto;
    padding: var(--container-padding);
    width: 100%;
}

/* Header */
.chat-header {
    text-align: center;
    padding: var(--space-lg) 0;
    margin-bottom: var(--space-lg);
    position: relative;
}

.sticky-header {
    position: sticky;
    top: 0;
    background: var(--bg-primary);
    z-index: 100;
    backdrop-filter: blur(10px);
    border-bottom: 1px solid rgba(242, 237, 230, 0.1);
    padding-bottom: var(--space-sm);
}

.chat-header::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 50%;
    transform: translateX(-50%);
    width: min(200px, 50%);
    height: 1px;
    background: linear-gradient(90deg, transparent, var(--text-tertiary), transparent);
}

.chat-title {
    font-size: var(--text-3xl);
    font-weight: 300;
    color: var(--text-primary);
    margin-bottom: var(--space-xs);
    letter-spacing: -0.025em;
}

.chat-subtitle {
    font-family: var(--font-mono);
    font-size: var(--text-xs);
    font-weight: 400;
    text-transform: uppercase;
    letter-spacing: 0.15em;
    color: var(--text-tertiary);
    opacity: 0;
    animation: fadeInUp 0.8s 0.3s ease-out forwards;
}

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* Messages Area */
.messages-area {
    flex: 1;
    display: flex;
    flex-direction: column;
    min-height: 0;
}

.messages-container {
    flex: 1;
    overflow-y: auto;
    padding: var(--space-md) 0;
    display: flex;
    flex-direction: column;
    gap: var(--space-lg);
    scroll-behavior: smooth;
}

/* Custom Scrollbar */
.messages-container::-webkit-scrollbar {
    width: 6px;
}

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

.messages-container::-webkit-scrollbar-thumb {
    background: var(--text-tertiary);
    border-radius: 3px;
    opacity: 0.6;
    transition: opacity var(--transition-base);
}

.messages-container::-webkit-scrollbar-thumb:hover {
    opacity: 1;
}

/* Message Styles */
.message {
    display: flex;
    flex-direction: column;
    opacity: 0;
    transform: translateY(30px) scale(0.95);
    animation: messageAppear var(--transition-spring) forwards;
}

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

.message-user {
    align-items: flex-end;
    margin-left: auto;
    max-width: min(70%, 600px);
}

.message-assistant {
    align-items: flex-start;
    margin-right: auto;
    max-width: min(85%, 700px);
}

.message-header {
    font-family: var(--font-mono);
    font-size: var(--text-xs);
    font-weight: 400;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    color: var(--text-tertiary);
    margin-bottom: var(--space-xs);
    opacity: 0.8;
    display: flex;
    align-items: center;
    gap: var(--space-xs);
}

.message-timestamp {
    opacity: 0.6;
}

.message-bubble {
    position: relative;
    padding: var(--space-md) var(--space-lg);
    border-radius: var(--radius-lg);
    backdrop-filter: blur(10px);
    transition: all var(--transition-base);
    word-wrap: break-word;
    overflow-wrap: break-word;
}

.message-user .message-bubble {
    background: linear-gradient(135deg, var(--bg-secondary) 0%, rgba(31, 29, 29, 0.9) 100%);
    border: 1px solid rgba(242, 237, 230, 0.1);
    border-bottom-right-radius: var(--radius-sm);
    box-shadow: var(--shadow-sm);
}

.message-assistant .message-bubble {
    background: linear-gradient(135deg, rgba(31, 29, 29, 0.8) 0%, rgba(20, 19, 19, 0.9) 100%);
    border: 1px solid rgba(242, 237, 230, 0.08);
    border-bottom-left-radius: var(--radius-sm);
    box-shadow: var(--shadow-md);
}

.message-bubble:hover {
    transform: translateY(-1px);
    box-shadow: var(--shadow-lg);
}

/* Message Content */
.message-content {
    font-size: var(--text-base);
    line-height: 1.7;
    color: var(--text-primary);
}

.message-content h1,
.message-content h2,
.message-content h3,
.message-content h4 {
    font-weight: 600;
    line-height: 1.3;
    margin: var(--space-md) 0 var(--space-sm) 0;
    color: var(--text-primary);
}

.message-content h1 {
    font-size: var(--text-2xl);
    border-bottom: 2px solid var(--text-tertiary);
    padding-bottom: var(--space-sm);
}

.message-content h2 {
    font-size: var(--text-xl);
    color: var(--text-secondary);
}

.message-content h3 {
    font-size: var(--text-lg);
    color: var(--text-secondary);
}

.message-content p {
    margin: var(--space-sm) 0;
}

.message-content p:first-child {
    margin-top: 0;
}

.message-content p:last-child {
    margin-bottom: 0;
}

.message-content strong {
    font-weight: 600;
    color: var(--accent);
}

.message-content em {
    font-style: italic;
    color: var(--text-secondary);
}

.message-content ul,
.message-content ol {
    margin: var(--space-sm) 0;
    padding-left: var(--space-lg);
}

.message-content li {
    margin: var(--space-xs) 0;
    color: var(--text-secondary);
}

.message-content li::marker {
    color: var(--text-tertiary);
}

/* Links with animated underline */
.message-content a {
    color: var(--text-tertiary);
    text-decoration: none;
    position: relative;
    font-weight: 500;
    transition: color var(--transition-base);
}

.message-content a:before {
    background-color: currentColor;
    bottom: -.1em;
    content: "";
    height: .0625em;
    left: 0;
    position: absolute;
    transform: scaleX(0) rotate(.001deg);
    transform-origin: right;
    transition: transform .735s cubic-bezier(.625,.05,0,1);
    width: 100%;
}

.message-content a:hover {
    color: var(--text-primary);
}

.message-content a:hover:before {
    transform: scaleX(1) rotate(.001deg);
    transform-origin: left;
}

/* Code and preformatted text */
.message-content code {
    background: var(--bg-primary);
    color: var(--text-secondary);
    padding: 0.25em 0.5em;
    border-radius: var(--radius-sm);
    font-family: var(--font-mono);
    font-size: 0.9em;
    border: 1px solid rgba(242, 237, 230, 0.1);
}

.message-content pre {
    background: var(--bg-primary);
    border: 1px solid rgba(242, 237, 230, 0.1);
    border-radius: var(--radius-md);
    padding: var(--space-md);
    overflow-x: auto;
    margin: var(--space-md) 0;
    font-family: var(--font-mono);
    font-size: var(--text-sm);
}

.message-content pre code {
    background: none;
    border: none;
    padding: 0;
}

.message-content blockquote {
    border-left: 4px solid var(--text-tertiary);
    padding-left: var(--space-md);
    margin: var(--space-md) 0;
    font-style: italic;
    color: var(--text-secondary);
    background: rgba(31, 29, 29, 0.3);
    border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
    padding: var(--space-sm) var(--space-md);
}

/* Image handling */
.message-content img {
    max-width: 100%;
    height: auto;
    border-radius: var(--radius-md);
    margin: var(--space-md) 0;
    box-shadow: var(--shadow-md);
    transition: transform var(--transition-base);
}

.message-content img:hover {
    transform: scale(1.02);
}

/* Welcome Message */
.welcome-section {
    text-align: center;
    padding: var(--space-xl);
    margin: var(--space-xl) 0;
    background: linear-gradient(135deg, rgba(31, 29, 29, 0.4) 0%, rgba(20, 19, 19, 0.6) 100%);
    border-radius: var(--radius-lg);
    border: 1px solid rgba(242, 237, 230, 0.05);
    backdrop-filter: blur(10px);
}

.welcome-title {
    font-size: var(--text-2xl);
    font-weight: 500;
    margin-bottom: var(--space-md);
    color: var(--text-primary);
    letter-spacing: -0.02em;
}

.welcome-description {
    font-size: var(--text-base);
    color: var(--text-secondary);
    line-height: 1.6;
    max-width: 600px;
    margin: 0 auto;
}

.welcome-suggestions {
    margin-top: var(--space-md);
    display: flex;
    flex-wrap: wrap;
    gap: var(--space-sm);
    justify-content: center;
    padding-bottom: var(--space-sm);
}

.suggestion-pill {
    background: rgba(31, 29, 29, 0.6);
    border: 1px solid rgba(242, 237, 230, 0.1);
    color: var(--text-secondary);
    padding: calc(var(--space-xs) * 0.8) calc(var(--space-md) * 0.8);
    border-radius: 999px;
    font-size: calc(var(--text-sm) * 0.9);
    font-family: var(--font-mono);
    text-transform: uppercase;
    letter-spacing: 0.05em;
    cursor: pointer;
    transition: all var(--transition-base);
}

.suggestion-pill:hover {
    background: var(--bg-secondary);
    border-color: var(--text-tertiary);
    color: var(--text-primary);
    transform: translateY(-2px);
}

/* Input Area */
.input-section {
    margin-top: var(--space-lg);
    padding-top: var(--space-lg);
    border-top: 1px solid rgba(242, 237, 230, 0.1);
    position: sticky;
    bottom: 0;
    background: linear-gradient(180deg, transparent 0%, var(--bg-primary) 20%);
    backdrop-filter: blur(10px);
}

.input-container {
    display: flex;
    gap: var(--space-md);
    align-items: flex-end;
    position: relative;
}

.input-wrapper {
    flex: 1;
    position: relative;
}

.chat-input {
    width: 100%;
    min-height: 3rem;
    max-height: 8rem;
    padding: var(--space-md) var(--space-lg);
    background: var(--bg-secondary);
    border: 2px solid transparent;
    border-radius: var(--radius-lg);
    color: var(--text-primary);
    font-family: var(--font-primary);
    font-size: var(--text-base);
    line-height: 1.5;
    resize: none;
    transition: all var(--transition-base);
    backdrop-filter: blur(10px);
}

.chat-input::placeholder {
    color: var(--text-tertiary);
}

.chat-input:focus {
    outline: none;
    border-color: rgba(242, 237, 230, 0.3);
    box-shadow: 0 0 0 4px rgba(242, 237, 230, 0.05);
    background: rgba(31, 29, 29, 0.8);
}

.send-button {
    height: 3rem;
    min-width: 4rem;
    background: linear-gradient(135deg, var(--accent) 0%, var(--text-secondary) 100%);
    color: var(--bg-primary);
    border: none;
    border-radius: var(--radius-lg);
    font-family: var(--font-mono);
    font-size: var(--text-sm);
    font-weight: 500;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    cursor: pointer;
    transition: all var(--transition-base);
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-xs);
}

.send-button:hover:not(:disabled) {
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

.send-button:active {
    transform: translateY(0);
}

.send-button:disabled {
    opacity: 0.5;
    cursor: not-allowed;
    transform: none;
}

/* Typing Indicator */
.typing-indicator {
    display: flex;
    align-items: center;
    gap: var(--space-sm);
    padding: var(--space-md);
    margin: var(--space-md) 0;
}

.typing-avatar {
    width: 2rem;
    height: 2rem;
    background: var(--bg-secondary);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-family: var(--font-mono);
    font-size: var(--text-xs);
    color: var(--text-tertiary);
}

.typing-content {
    display: flex;
    align-items: center;
    gap: var(--space-sm);
}

.typing-text {
    font-family: var(--font-mono);
    font-size: var(--text-xs);
    text-transform: uppercase;
    letter-spacing: 0.1em;
    color: var(--text-tertiary);
}

.typing-dots {
    display: flex;
    gap: 0.25rem;
}

.typing-dot {
    width: 6px;
    height: 6px;
    background: var(--text-tertiary);
    border-radius: 50%;
    animation: typingPulse 1.4s infinite ease-in-out;
}

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

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

@keyframes typingPulse {
    0%, 80%, 100% {
        opacity: 0.3;
        transform: scale(0.8);
    }
    40% {
        opacity: 1;
        transform: scale(1.2);
    }
}

/* Responsive Design */
@media (max-width: 768px) {
    :root {
        --container-padding: clamp(1rem, 4vw, 1.5rem);
    }

    .chat-wrapper {
        padding: var(--container-padding);
    }

    .message-user {
        max-width: 85%;
    }

    .message-assistant {
        max-width: 95%;
    }

    .input-container {
        flex-direction: column;
        gap: var(--space-sm);
    }

    .send-button {
        width: 100%;
        min-width: auto;
    }

    .welcome-suggestions {
        flex-direction: column;
        align-items: stretch;
    }

    .suggestion-pill {
        text-align: center;
    }
}

@media (max-width: 480px) {
    .message-bubble {
        padding: var(--space-sm) var(--space-md);
    }

    .chat-input {
        padding: var(--space-sm) var(--space-md);
    }
}

/* Accessibility */
@media (prefers-reduced-motion: reduce) {
    * {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }
}

/* Focus management */
.visually-hidden {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border: 0;
}