/* CSS Variables */
:root {
    --bg-primary: #0f0f15;
    --bg-secondary: #16161f;
    --bg-tertiary: #1e1e2a;
    --bg-hover: #252535;
    --text-primary: #ffffff;
    --text-secondary: #a0a0b0;
    --text-muted: #6b6b7b;
    --accent-primary: #8b5cf6;
    --accent-secondary: #a78bfa;
    --accent-glow: rgba(139, 92, 246, 0.3);
    --success: #10b981;
    --error: #ef4444;
    --border-color: #2a2a3a;
    --code-bg: #1a1a24;
    --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
    --font-mono: 'JetBrains Mono', 'Fira Code', monospace;
    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 16px;
    --shadow-lg: 0 20px 40px rgba(0, 0, 0, 0.4);
}

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

html, body {
    height: 100%;
    overflow: hidden;
}

body {
    font-family: var(--font-sans);
    background: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.6;
}

/* App Container */
.app-container {
    display: flex;
    flex-direction: column;
    height: 100vh;
    max-width: 1200px;
    margin: 0 auto;
    background: var(--bg-primary);
}

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

.logo {
    display: flex;
    align-items: center;
    gap: 12px;
}

.logo-icon {
    width: 40px;
    height: 40px;
    background: linear-gradient(135deg, var(--accent-primary), var(--accent-secondary));
    border-radius: var(--radius-sm);
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: 0 4px 12px var(--accent-glow);
}

.logo-icon svg {
    width: 22px;
    height: 22px;
    color: white;
}

.logo h1 {
    font-size: 1.25rem;
    font-weight: 700;
    background: linear-gradient(135deg, var(--text-primary), var(--accent-secondary));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.badge {
    font-size: 0.7rem;
    font-weight: 600;
    padding: 4px 10px;
    background: var(--accent-primary);
    color: white;
    border-radius: 20px;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.model-selector {
    display: flex;
    align-items: center;
    gap: 10px;
}

.model-selector label {
    font-size: 0.85rem;
    color: var(--text-secondary);
}

.model-selector select {
    padding: 10px 16px;
    background: var(--bg-tertiary);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-sm);
    color: var(--text-primary);
    font-family: var(--font-sans);
    font-size: 0.85rem;
    cursor: pointer;
    transition: all 0.2s ease;
}

.model-selector select:hover {
    border-color: var(--accent-primary);
}

.model-selector select:focus {
    outline: none;
    border-color: var(--accent-primary);
    box-shadow: 0 0 0 3px var(--accent-glow);
}

/* Chat Container */
.chat-container {
    flex: 1;
    overflow-y: auto;
    padding: 24px;
    display: flex;
    flex-direction: column;
    gap: 20px;
}

.chat-container::-webkit-scrollbar {
    width: 6px;
}

.chat-container::-webkit-scrollbar-track {
    background: var(--bg-primary);
}

.chat-container::-webkit-scrollbar-thumb {
    background: var(--border-color);
    border-radius: 3px;
}

/* Welcome Message */
.welcome-message {
    text-align: center;
    padding: 60px 20px;
    animation: fadeIn 0.5s ease;
}

.welcome-icon {
    font-size: 4rem;
    margin-bottom: 20px;
    animation: float 3s ease-in-out infinite;
}

@keyframes float {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-10px); }
}

.welcome-message h2 {
    font-size: 1.75rem;
    font-weight: 700;
    margin-bottom: 12px;
    background: linear-gradient(135deg, var(--text-primary), var(--accent-secondary));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.welcome-message p {
    color: var(--text-secondary);
    max-width: 500px;
    margin: 0 auto 30px;
}

.suggestions {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 12px;
    max-width: 700px;
    margin: 0 auto;
}

.suggestion {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 14px 18px;
    background: var(--bg-tertiary);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    color: var(--text-primary);
    font-family: var(--font-sans);
    font-size: 0.9rem;
    cursor: pointer;
    transition: all 0.2s ease;
    text-align: left;
}

.suggestion:hover {
    background: var(--bg-hover);
    border-color: var(--accent-primary);
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.3);
}

.suggestion-icon {
    font-size: 1.2rem;
}

/* Message Styles */
.message {
    display: flex;
    gap: 14px;
    animation: slideIn 0.3s ease;
}

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

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

.message.user {
    flex-direction: row-reverse;
}

.message-avatar {
    width: 38px;
    height: 38px;
    border-radius: var(--radius-sm);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.1rem;
    flex-shrink: 0;
}

.message.user .message-avatar {
    background: linear-gradient(135deg, #3b82f6, #1d4ed8);
}

.message.assistant .message-avatar {
    background: linear-gradient(135deg, var(--accent-primary), var(--accent-secondary));
}

.message-content {
    max-width: 75%;
    padding: 16px 20px;
    border-radius: var(--radius-lg);
    line-height: 1.7;
}

.message.user .message-content {
    background: linear-gradient(135deg, #3b82f6, #2563eb);
    color: white;
    border-bottom-right-radius: 4px;
}

.message.assistant .message-content {
    background: var(--bg-tertiary);
    border: 1px solid var(--border-color);
    border-bottom-left-radius: 4px;
}

/* Code Blocks */
.message-content pre {
    background: var(--code-bg);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-sm);
    padding: 16px;
    margin: 12px 0;
    overflow-x: auto;
    position: relative;
}

.message-content pre code {
    font-family: var(--font-mono);
    font-size: 0.85rem;
    color: #e2e8f0;
    line-height: 1.6;
}

.message-content code:not(pre code) {
    background: var(--code-bg);
    padding: 2px 8px;
    border-radius: 4px;
    font-family: var(--font-mono);
    font-size: 0.85em;
    color: var(--accent-secondary);
}

/* Copy Button */
.copy-btn {
    position: absolute;
    top: 8px;
    right: 8px;
    padding: 6px 12px;
    background: var(--bg-hover);
    border: 1px solid var(--border-color);
    border-radius: 6px;
    color: var(--text-secondary);
    font-size: 0.75rem;
    cursor: pointer;
    transition: all 0.2s ease;
    opacity: 0;
}

.message-content pre:hover .copy-btn {
    opacity: 1;
}

.copy-btn:hover {
    background: var(--accent-primary);
    color: white;
    border-color: var(--accent-primary);
}

/* Typing Indicator */
.typing-indicator {
    display: flex;
    gap: 6px;
    padding: 16px 20px;
}

.typing-indicator span {
    width: 8px;
    height: 8px;
    background: var(--accent-primary);
    border-radius: 50%;
    animation: bounce 1.4s infinite ease-in-out;
}

.typing-indicator span:nth-child(1) { animation-delay: -0.32s; }
.typing-indicator span:nth-child(2) { animation-delay: -0.16s; }
.typing-indicator span:nth-child(3) { animation-delay: 0s; }

@keyframes bounce {
    0%, 80%, 100% { transform: scale(0.8); opacity: 0.5; }
    40% { transform: scale(1); opacity: 1; }
}

/* Input Area */
.input-area {
    padding: 20px 24px;
    background: var(--bg-secondary);
    border-top: 1px solid var(--border-color);
    flex-shrink: 0;
}

.input-wrapper {
    display: flex;
    align-items: flex-end;
    gap: 12px;
    background: var(--bg-tertiary);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    padding: 12px 16px;
    transition: all 0.2s ease;
}

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

.input-wrapper textarea {
    flex: 1;
    background: transparent;
    border: none;
    color: var(--text-primary);
    font-family: var(--font-sans);
    font-size: 0.95rem;
    resize: none;
    max-height: 150px;
    line-height: 1.5;
}

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

.input-wrapper textarea:focus {
    outline: none;
}

#sendBtn {
    width: 44px;
    height: 44px;
    background: linear-gradient(135deg, var(--accent-primary), var(--accent-secondary));
    border: none;
    border-radius: var(--radius-sm);
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all 0.2s ease;
    flex-shrink: 0;
}

#sendBtn:hover {
    transform: scale(1.05);
    box-shadow: 0 4px 12px var(--accent-glow);
}

#sendBtn:disabled {
    opacity: 0.5;
    cursor: not-allowed;
    transform: none;
}

#sendBtn svg {
    width: 20px;
    height: 20px;
    color: white;
}

.disclaimer {
    text-align: center;
    font-size: 0.75rem;
    color: var(--text-muted);
    margin-top: 12px;
}

/* Responsive */
@media (max-width: 768px) {
    .header {
        flex-direction: column;
        gap: 16px;
        padding: 16px;
    }

    .model-selector {
        width: 100%;
    }

    .model-selector select {
        flex: 1;
    }

    .suggestions {
        grid-template-columns: 1fr;
    }

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

    .welcome-message {
        padding: 40px 16px;
    }

    .welcome-message h2 {
        font-size: 1.4rem;
    }
}