/* Reset and Base Styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    --primary-color: #10a37f;
    --primary-hover: #0d8a6a;
    --secondary-color: #6366f1;
    --background: #212121;
    --surface: #2f2f2f;
    --surface-hover: #3a3a3a;
    --border: #404040;
    --text-primary: #ececec;
    --text-secondary: #b4b4b4;
    --success: #10b981;
    --error: #ef4444;
    --warning: #f59e0b;
    --dark-bg: #171717;
    --darker-bg: #0d0d0d;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Roboto', 'Oxygen', 'Ubuntu', 'Cantarell', sans-serif;
    line-height: 1.6;
    color: var(--text-primary);
    background-color: var(--dark-bg);
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* Navigation */
.navbar {
    background-color: var(--background);
    border-bottom: 1px solid var(--border);
    padding: 1rem 0;
    position: sticky;
    top: 0;
    z-index: 100;
}

.navbar .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.nav-brand h1 {
    font-size: 1.5rem;
    color: var(--text-primary);
    font-weight: 700;
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: 2rem;
}

.nav-menu a {
    text-decoration: none;
    color: var(--text-secondary);
    font-weight: 500;
    transition: color 0.3s;
}

.nav-menu a:hover,
.nav-menu a.active {
    color: var(--text-primary);
}

.hamburger {
    display: none;
    flex-direction: column;
    gap: 4px;
    cursor: pointer;
}

.hamburger span {
    width: 25px;
    height: 3px;
    background-color: var(--text-primary);
    transition: 0.3s;
}

/* Buttons */
.btn {
    padding: 0.75rem 1.5rem;
    border-radius: 0.5rem;
    font-weight: 600;
    text-decoration: none;
    display: inline-block;
    transition: all 0.3s;
    border: none;
    cursor: pointer;
    font-size: 1rem;
}

.btn-primary {
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 100%);
    color: white;
    position: relative;
    overflow: hidden;
}

.btn-primary::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(135deg, var(--secondary-color) 0%, var(--primary-color) 100%);
    transition: left 0.4s;
}

.btn-primary:hover::before {
    left: 0;
}

.btn-primary:hover {
    transform: translateY(-3px);
    box-shadow: 0 10px 25px rgba(99, 102, 241, 0.4);
}

.btn-primary * {
    position: relative;
    z-index: 1;
}

.btn-secondary {
    background-color: var(--surface);
    color: var(--text-primary);
    border: 2px solid var(--border);
}

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

.btn-outline {
    background-color: transparent;
    color: var(--text-secondary);
    border: 1px solid var(--border);
}

.btn-outline:hover {
    background-color: var(--surface);
}

.btn-full {
    width: 100%;
    text-align: center;
}

.btn-large {
    padding: 1rem 2rem;
    font-size: 1.125rem;
}

/* Hero Section */
.hero {
    padding: 6rem 0;
    background: var(--darker-bg);
    color: white;
    text-align: center;
    border-bottom: 1px solid var(--border);
}

.hero-title {
    font-size: 3.5rem;
    margin-bottom: 1rem;
    font-weight: 800;
    position: relative;
    z-index: 1;
    text-shadow: 0 2px 10px rgba(0,0,0,0.2);
    line-height: 1.2;
}

.hero-subtitle {
    font-size: 1.5rem;
    margin-bottom: 2.5rem;
    opacity: 0.95;
    position: relative;
    z-index: 1;
    text-shadow: 0 1px 5px rgba(0,0,0,0.15);
}

.hero-buttons {
    display: flex;
    gap: 1rem;
    justify-content: center;
    flex-wrap: wrap;
    position: relative;
    z-index: 1;
}

.hero-buttons .btn {
    padding: 1rem 2.5rem;
    font-size: 1.125rem;
    font-weight: 600;
    box-shadow: 0 10px 25px rgba(0,0,0,0.2);
}

.hero-buttons .btn-primary {
    background: white;
    color: var(--primary-color);
}

.hero-buttons .btn-primary:hover {
    background: #f9fafb;
    transform: translateY(-3px);
    box-shadow: 0 15px 35px rgba(0,0,0,0.25);
}

.hero-buttons .btn-secondary {
    background: rgba(255,255,255,0.2);
    color: white;
    border: 2px solid white;
    backdrop-filter: blur(10px);
}

.hero-buttons .btn-secondary:hover {
    background: rgba(255,255,255,0.3);
    transform: translateY(-3px);
}

/* Features Section */
.features {
    padding: 5rem 0;
    background-color: var(--dark-bg);
}

.section-title {
    text-align: center;
    font-size: 2.5rem;
    margin-bottom: 3rem;
    color: var(--text-primary);
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
}

.feature-card {
    background-color: var(--surface);
    padding: 2.5rem;
    border-radius: 1rem;
    border: 1px solid var(--border);
    transition: all 0.3s;
}

.feature-card:hover {
    transform: translateY(-5px);
    background-color: var(--surface-hover);
    border-color: var(--primary-color);
}

.feature-icon {
    font-size: 3rem;
    margin-bottom: 1rem;
}

.feature-card h3 {
    margin-bottom: 0.5rem;
    color: var(--text-primary);
}

.feature-card p {
    color: var(--text-secondary);
}

/* Models Section */
.models {
    padding: 5rem 0;
    background-color: var(--background);
}

.models-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 1.5rem;
}

.model-card {
    background: var(--surface);
    padding: 1.5rem;
    border-radius: 0.75rem;
    border: 1px solid var(--border);
    text-align: center;
    transition: all 0.3s;
    cursor: pointer;
}

.model-card:hover {
    background-color: var(--surface-hover);
    border-color: var(--primary-color);
    transform: translateY(-3px);
}

.model-card h3 {
    color: var(--text-primary);
    margin-bottom: 0.5rem;
    font-size: 1rem;
}

.model-card p {
    color: var(--text-secondary);
    font-size: 0.9rem;
}

/* CTA Section */
.cta {
    padding: 5rem 0;
    background-color: var(--surface);
    color: var(--text-primary);
    text-align: center;
    border-top: 1px solid var(--border);
}

.cta h2 {
    font-size: 2.5rem;
    margin-bottom: 1rem;
}

.cta p {
    font-size: 1.25rem;
    margin-bottom: 2rem;
    opacity: 0.9;
}

/* Footer */
.footer {
    background-color: var(--darker-bg);
    color: var(--text-secondary);
    padding: 3rem 0 1rem;
    border-top: 1px solid var(--border);
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 2rem;
    margin-bottom: 2rem;
}

.footer-section h3,
.footer-section h4 {
    margin-bottom: 1rem;
}

.footer-section ul {
    list-style: none;
}

.footer-section ul li {
    margin-bottom: 0.5rem;
}

.footer-section a {
    color: var(--text-secondary);
    text-decoration: none;
    transition: color 0.3s;
}

.footer-section a:hover {
    color: var(--text-primary);
}

.footer-bottom {
    border-top: 1px solid rgba(255,255,255,0.1);
    padding-top: 1rem;
    text-align: center;
    color: rgba(255,255,255,0.6);
}

/* Chat Interface */
.chat-container {
    display: flex;
    flex-direction: column;
    height: calc(100vh - 73px);
    background-color: var(--dark-bg);
}

.chat-sidebar {
    width: 100%;
    background-color: var(--background);
    border-bottom: 1px solid var(--border);
    padding: 1.5rem;
    overflow-x: auto;
    overflow-y: hidden;
}

.sidebar-header {
    margin-bottom: 1rem;
}

.sidebar-header h2 {
    font-size: 1.5rem;
    color: var(--text-primary);
}

.model-selector {
    display: flex;
    gap: 0.75rem;
    overflow-x: auto;
    padding-bottom: 0.5rem;
}

.model-dropdown {
    display: none; /* Hide dropdown, use horizontal buttons instead */
}

/* Horizontal Model Buttons */
.model-btn {
    flex-shrink: 0;
    padding: 0.75rem 1.5rem;
    background-color: var(--surface);
    border: 1px solid var(--border);
    border-radius: 0.75rem;
    color: var(--text-primary);
    font-size: 0.9rem;
    cursor: pointer;
    transition: all 0.2s;
    white-space: nowrap;
}

.model-btn:hover {
    background-color: var(--surface-hover);
    border-color: var(--primary-color);
}

.model-btn.active {
    background-color: var(--primary-color);
    border-color: var(--primary-color);
    color: white;
}

.sidebar-actions {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
    margin-bottom: 2rem;
}

.sidebar-info {
    background-color: var(--background);
    padding: 1rem;
    border-radius: 0.5rem;
    border: 1px solid var(--border);
}

.sidebar-info p {
    font-size: 0.9rem;
    margin-bottom: 0.5rem;
}

.sidebar-info p:last-child {
    margin-bottom: 0;
    color: var(--primary-color);
    font-weight: 600;
}

/* Chat Main Area */
.chat-main {
    flex: 1;
    display: flex;
    flex-direction: column;
    background-color: var(--dark-bg);
}

.chat-header {
    padding: 1rem 1.5rem;
    border-bottom: 1px solid var(--border);
    display: flex;
    justify-content: space-between;
    align-items: center;
    background-color: var(--background);
}

.chat-status {
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.status-dot {
    width: 10px;
    height: 10px;
    border-radius: 50%;
    background-color: var(--success);
    animation: pulse 2s infinite;
}

@keyframes pulse {
    0%, 100% {
        opacity: 1;
    }
    50% {
        opacity: 0.5;
    }
}

.chat-messages {
    flex: 1;
    overflow-y: auto;
    padding: 2rem;
}

.welcome-message {
    text-align: center;
    max-width: 600px;
    margin: 4rem auto;
}

.welcome-message h2 {
    font-size: 2rem;
    margin-bottom: 1rem;
    color: var(--text-primary);
}

.welcome-message p {
    font-size: 1.125rem;
    color: var(--text-secondary);
    margin-bottom: 2rem;
}

.suggestions {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 1rem;
}

.suggestion-btn {
    padding: 1rem;
    border: 2px solid var(--border);
    border-radius: 0.75rem;
    background-color: var(--background);
    cursor: pointer;
    transition: all 0.3s;
    font-size: 0.9rem;
    color: var(--text-primary);
}

.suggestion-btn:hover {
    border-color: var(--primary-color);
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(0,0,0,0.1);
}

/* Message Bubbles */
.message {
    margin-bottom: 1.5rem;
    display: flex;
    gap: 1rem;
    animation: fadeIn 0.3s;
}

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

.message-avatar {
    width: 36px;
    height: 36px;
    border-radius: 0.5rem;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.125rem;
    flex-shrink: 0;
}

.user-message .message-avatar {
    background-color: var(--primary-color);
    color: white;
}

.ai-message .message-avatar {
    background-color: var(--surface);
    color: var(--text-primary);
}

.message-content {
    flex: 1;
    background-color: transparent;
    padding: 0 1rem;
    border-radius: 0;
    border: none;
}

.user-message .message-content {
    background-color: transparent;
    color: var(--text-primary);
}

.message-text {
    line-height: 1.6;
    white-space: pre-wrap;
    word-wrap: break-word;
}

.message-loading {
    display: flex;
    gap: 0.5rem;
    padding: 0.5rem 0;
}

.dot {
    width: 8px;
    height: 8px;
    border-radius: 50%;
    background-color: var(--text-secondary);
    animation: bounce 1.4s infinite ease-in-out both;
}

.dot:nth-child(1) {
    animation-delay: -0.32s;
}

.dot:nth-child(2) {
    animation-delay: -0.16s;
}

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

/* Chat Input */
.chat-input-container {
    padding: 1.5rem;
    border-top: 1px solid var(--border);
    background-color: var(--dark-bg);
}

.chat-input-wrapper {
    display: flex;
    gap: 1rem;
    max-width: 900px;
    margin: 0 auto;
}

.chat-input {
    flex: 1;
    padding: 1rem;
    background-color: var(--surface);
    color: var(--text-primary);
    border: 1px solid var(--border);
    border-radius: 0.75rem;
    font-size: 1rem;
    font-family: inherit;
    resize: none;
    max-height: 200px;
    transition: all 0.2s;
}

.chat-input:focus {
    outline: none;
    background-color: var(--surface-hover);
    border-color: var(--primary-color);
}

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

.send-btn {
    width: 44px;
    height: 44px;
    border-radius: 0.5rem;
    background-color: var(--primary-color);
    color: white;
    border: none;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all 0.2s;
    flex-shrink: 0;
}

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

.send-btn:disabled {
    background-color: var(--surface);
    cursor: not-allowed;
    opacity: 0.5;
}

.input-hint {
    text-align: center;
    font-size: 0.875rem;
    color: var(--text-secondary);
    margin-top: 0.5rem;
}

/* Responsive Design */
@media (max-width: 768px) {
    .nav-menu {
        display: none;
    }
    
    .hamburger {
        display: flex;
    }
    
    .hero-title {
        font-size: 2rem;
    }
    
    .hero-subtitle {
        font-size: 1rem;
    }
    
    .features-grid,
    .models-grid {
        grid-template-columns: 1fr;
    }
    
    .chat-container {
        flex-direction: column;
    }
    
    .chat-sidebar {
        width: 100%;
        max-height: 200px;
        border-right: none;
        border-bottom: 1px solid var(--border);
    }
    
    .suggestions {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 480px) {
    .hero {
        padding: 3rem 0;
    }
    
    .hero-title {
        font-size: 1.5rem;
    }
    
    .section-title {
        font-size: 1.75rem;
    }
    
    .chat-messages {
        padding: 1rem;
    }
}