:root {
    --color-black: #080808;
    --color-white: #ffffff;
    --color-gray-100: #f5f5f5;
    --color-gray-200: #e5e5e5;
    --color-gray-500: #737373;
    --color-gray-800: #262626;
    
    --font-heading: 'Playfair Display', serif;
    --font-body: 'DM Sans', sans-serif;
    
    --spacing-sm: 1rem;
    --spacing-md: 2rem;
    --spacing-lg: 4rem;
    --spacing-xl: 6rem;
    
    --radius-sm: 4px;
    --radius-md: 8px;
    --radius-lg: 16px;
    
    --transition: all 0.3s ease;
}

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

body {
    font-family: var(--font-body);
    color: var(--color-black);
    background-color: var(--color-white);
    line-height: 1.6;
    font-size: 16px;
    -webkit-font-smoothing: antialiased;
}

/* Typography */
h1, h2, h3, .logo {
    font-family: var(--font-heading);
    font-weight: 700;
    color: var(--color-black);
    line-height: 1.2;
}

.text-white { color: var(--color-white) !important; }
.text-center { text-align: center; }

/* Layout Utilities */
.container {
    width: 100%;
    max-width: 1100px;
    margin: 0 auto;
    padding: 0 1.5rem;
}

.py-lg { padding-top: var(--spacing-lg); padding-bottom: var(--spacing-lg); }
.py-xl { padding-top: var(--spacing-xl); padding-bottom: var(--spacing-xl); }
.pb-lg { padding-bottom: var(--spacing-lg); }
.pt-xl { padding-top: var(--spacing-xl); }
.pt-lg { padding-top: var(--spacing-lg); }
.pb-md { padding-bottom: var(--spacing-md); }
.pt-md { padding-top: var(--spacing-md); }
.mt-lg { margin-top: var(--spacing-lg); }
.mt-xl { margin-top: var(--spacing-xl); }
.mb-xl { margin-bottom: var(--spacing-xl); }

.bg-light { background-color: var(--color-gray-100); }
.bg-dark { background-color: var(--color-black); color: var(--color-white); }

/* Components */
.button {
    display: inline-block;
    font-family: var(--font-body);
    font-weight: 500;
    text-decoration: none;
    cursor: pointer;
    border: none;
    transition: var(--transition);
    border-radius: var(--radius-sm);
}

.button-primary {
    background-color: var(--color-black);
    color: var(--color-white);
    padding: 1rem 2rem;
    font-size: 1rem;
}

.button-primary:hover {
    background-color: var(--color-gray-800);
}

.button-small {
    background-color: transparent;
    color: var(--color-black);
    border: 1px solid var(--color-gray-200);
    padding: 0.5rem 1rem;
    font-size: 0.875rem;
}

.button-small:hover {
    border-color: var(--color-black);
}

.input-field {
    font-family: var(--font-body);
    padding: 1rem;
    border: 1px solid var(--color-gray-200);
    border-radius: var(--radius-sm);
    font-size: 1rem;
    width: 100%;
    outline: none;
    transition: var(--transition);
}

.input-field:focus {
    border-color: var(--color-black);
}

.cta-form {
    display: flex;
    flex-direction: column;
    gap: 1rem;
    max-width: 400px;
    margin: 2rem auto 1rem;
}

/* Navbar */
.navbar {
    padding: 1.5rem 0;
    position: sticky;
    top: 0;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    z-index: 100;
    border-bottom: 1px solid var(--color-gray-100);
}

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

.logo {
    font-size: 1.5rem;
    letter-spacing: -0.5px;
}

/* Hero Section */
.hero-headline {
    font-size: 2.5rem;
    margin-bottom: 1.5rem;
    letter-spacing: -1px;
}

.hero-subheadline {
    font-size: 1.125rem;
    color: var(--color-gray-500);
    max-width: 600px;
    margin: 0 auto;
}

.note {
    font-size: 0.875rem;
    color: var(--color-gray-500);
}

/* Problem Section */
.problem-grid {
    display: flex;
    flex-direction: column;
    gap: 2rem;
}

.problem-card {
    background: var(--color-white);
    padding: 2rem;
    border-radius: var(--radius-lg);
    box-shadow: 0 4px 20px rgba(0,0,0,0.03);
}

.card-icon {
    color: var(--color-black);
    margin-bottom: 1rem;
}

.problem-card h3 {
    font-size: 1.25rem;
    margin-bottom: 0.5rem;
}

.problem-card p {
    color: var(--color-gray-500);
    margin-bottom: 1.5rem;
}

.chat-bubble {
    background: var(--color-gray-100);
    padding: 0.875rem 1.25rem;
    border-radius: 18px;
    font-size: 0.875rem;
    display: inline-block;
}

.user-bubble {
    border-bottom-left-radius: 4px;
}

/* Demo Section */
.section-headline {
    font-size: 2rem;
    margin-bottom: 2.5rem;
}

.chat-window {
    max-width: 400px;
    margin: 0 auto 2rem;
    background: var(--color-gray-100);
    border-radius: var(--radius-lg);
    overflow: hidden;
    text-align: left;
    box-shadow: 0 10px 30px rgba(0,0,0,0.05);
}

.chat-header {
    background: var(--color-white);
    padding: 1rem;
    display: flex;
    align-items: center;
    gap: 1rem;
    border-bottom: 1px solid var(--color-gray-200);
}

.avatar {
    width: 40px;
    height: 40px;
    background: var(--color-black);
    color: var(--color-white);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 700;
    font-size: 0.875rem;
}

.header-info {
    display: flex;
    flex-direction: column;
}

.header-info strong {
    font-size: 0.95rem;
}

.header-info span {
    font-size: 0.75rem;
    color: var(--color-gray-500);
}

.chat-messages {
    padding: 1.5rem;
    height: 400px;
    overflow-y: auto;
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.msg {
    max-width: 85%;
    padding: 0.75rem 1rem;
    border-radius: 18px;
    font-size: 0.95rem;
    animation: fadeIn 0.3s ease forwards;
    opacity: 0;
}

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

.msg-user {
    background: var(--color-white);
    border: 1px solid var(--color-gray-200);
    align-self: flex-start;
    border-bottom-left-radius: 4px;
}

.msg-ai {
    background: var(--color-black);
    color: var(--color-white);
    align-self: flex-end;
    border-bottom-right-radius: 4px;
}

.typing-indicator {
    display: flex;
    gap: 4px;
    padding: 1rem;
    background: var(--color-black);
    align-self: flex-end;
    border-radius: 18px;
    border-bottom-right-radius: 4px;
}

.dot {
    width: 6px;
    height: 6px;
    background: var(--color-white);
    border-radius: 50%;
    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); }
}

.demo-footer {
    color: var(--color-gray-500);
    font-size: 0.875rem;
}

/* Target Audience Section */
.icon-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 2rem;
    max-width: 800px;
    margin: 0 auto;
}

.icon-item {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 1rem;
}

.icon {
    font-size: 2.5rem;
    width: 80px;
    height: 80px;
    background: var(--color-gray-800);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
}

/* Final CTA */
.final-description {
    color: var(--color-gray-500);
    margin-bottom: 2rem;
}

/* Footer */
.footer {
    border-top: 1px solid var(--color-gray-200);
    padding: 2rem 0;
    text-align: center;
    color: var(--color-gray-500);
    font-size: 0.875rem;
}

/* Responsive - Desktop First */
@media (min-width: 768px) {
    .hero-headline { font-size: 4rem; }
    .hero-subheadline { font-size: 1.25rem; }
    
    .cta-form {
        flex-direction: row;
        max-width: 600px;
    }
    
    .problem-grid {
        flex-direction: row;
    }
    
    .problem-card {
        flex: 1;
    }
    
    .section-headline { font-size: 2.5rem; }
    
    .icon-grid {
        grid-template-columns: repeat(3, 1fr);
    }
}