/* ====================================================
   AIRobo Studio — Minimalist Styles
   ==================================================== */

:root {
    --bg-color: #ffffff;
    --surface-color: #f9fafb; /* Light gray for cards/sections */
    --text-main: #111827; /* Dark gray, almost black */
    --text-muted: #4b5563; /* Medium gray */
    --primary: #2563eb; /* Vibrant blue */
    --primary-hover: #1d4ed8;
    --secondary: #f97316; /* Accent orange */
    --secondary-hover: #ea580c;
    --border-color: #e5e7eb;
    --radius: 8px;
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    --transition: all 0.2s ease;
}

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

body {
    font-family: 'Inter', system-ui, -apple-system, sans-serif;
    background-color: var(--bg-color);
    color: var(--text-main);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
}

.container {
    max-width: 1100px;
    margin: 0 auto;
    padding: 0 24px;
}

/* ====================================================
   Buttons
   ==================================================== */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    padding: 10px 20px;
    border-radius: var(--radius);
    font-weight: 500;
    font-size: 0.95rem;
    text-decoration: none;
    cursor: pointer;
    transition: var(--transition);
    border: 1px solid transparent;
}

.btn-large {
    padding: 14px 28px;
    font-size: 1.1rem;
    font-weight: 600;
    border-radius: 10px;
}

.btn-primary {
    background-color: var(--primary);
    color: #fff;
    box-shadow: var(--shadow-sm);
}

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

.btn-secondary {
    background-color: var(--secondary);
    color: #fff;
}

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

.btn-outline {
    background-color: transparent;
    color: var(--text-main);
    border-color: var(--border-color);
}

.btn-outline:hover {
    background-color: var(--surface-color);
    border-color: #d1d5db;
}

/* ====================================================
   Navigation
   ==================================================== */
.navbar {
    padding: 20px 0;
    border-bottom: 1px solid var(--border-color);
    background-color: rgba(255, 255, 255, 0.9);
    backdrop-filter: blur(8px);
    position: sticky;
    top: 0;
    z-index: 100;
}

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

.nav-brand {
    display: flex;
    align-items: center;
    gap: 12px;
    text-decoration: none;
    color: var(--text-main);
}

.nav-logo {
    height: 32px;
    width: auto;
    object-fit: contain;
}

.nav-title {
    font-weight: 700;
    font-size: 1.25rem;
    letter-spacing: -0.02em;
}

/* ====================================================
   Hero Section
   ==================================================== */
.hero {
    padding: 80px 0 60px;
    text-align: center;
    background: radial-gradient(circle at 50% 0%, #f3f4f6 0%, #ffffff 70%);
}

.hero-container {
    max-width: 800px;
}

.hero-title {
    font-size: 3.5rem;
    font-weight: 800;
    letter-spacing: -0.03em;
    line-height: 1.1;
    margin-bottom: 24px;
    color: var(--text-main);
}

.hero-subtitle {
    font-size: 1.25rem;
    color: var(--text-muted);
    margin-bottom: 40px;
    max-width: 600px;
    margin-inline: auto;
}

.hero-cta {
    margin-bottom: 60px;
}

.hero-visual {
    margin: 0 auto;
    max-width: 100%;
    border-radius: 12px;
    box-shadow: 0 20px 40px -10px rgba(0,0,0,0.1);
    overflow: hidden;
    border: 1px solid var(--border-color);
}

.hero-image {
    width: 100%;
    height: auto;
    display: block;
}

/* ====================================================
   Explanation Section (3 Columns)
   ==================================================== */
.explanation-section {
    padding: 80px 0;
    background-color: var(--bg-color);
}

.audience-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 24px;
}

.feature-card {
    background-color: var(--surface-color);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    padding: 32px 24px;
    text-align: left;
    transition: var(--transition);
}

.feature-card:hover {
    box-shadow: var(--shadow-md);
    transform: translateY(-2px);
}

.feature-icon {
    font-size: 2rem;
    margin-bottom: 16px;
}

.feature-title {
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: 8px;
}

.feature-goal {
    color: var(--primary);
    font-size: 0.95rem;
    margin-bottom: 16px;
}

.feature-list {
    list-style: none;
    color: var(--text-muted);
    font-size: 0.95rem;
}

.feature-list li {
    position: relative;
    padding-left: 20px;
    margin-bottom: 12px;
    line-height: 1.5;
}

.feature-list li::before {
    content: '•';
    position: absolute;
    left: 0;
    color: var(--primary);
    font-weight: bold;
}

/* ====================================================
   Community Section
   ==================================================== */
.community-section {
    padding: 60px 0;
    border-top: 1px solid var(--border-color);
    background-color: var(--surface-color);
}

.community-container {
    display: flex;
    justify-content: center;
}

.community-links {
    display: flex;
    flex-wrap: wrap;
    gap: 16px;
    justify-content: center;
}

/* ====================================================
   Newsletter Section
   ==================================================== */
.newsletter-section {
    padding: 100px 0;
    text-align: center;
    background-color: var(--bg-color);
}

.newsletter-container {
    max-width: 600px;
}

.newsletter-title {
    font-size: 2rem;
    font-weight: 700;
    margin-bottom: 12px;
    letter-spacing: -0.02em;
}

.newsletter-subtitle {
    color: var(--text-muted);
    margin-bottom: 32px;
    font-size: 1.1rem;
}

.newsletter-form {
    display: flex;
    gap: 12px;
    margin-bottom: 16px;
}

.newsletter-input {
    flex: 1;
    padding: 12px 16px;
    border: 1px solid var(--border-color);
    border-radius: var(--radius);
    font-family: inherit;
    font-size: 1rem;
    outline: none;
    transition: var(--transition);
}

.newsletter-input:focus {
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.1);
}

.spam-promise {
    font-size: 0.85rem;
    color: var(--text-muted);
}

/* ====================================================
   Footer
   ==================================================== */
.footer {
    padding: 40px 0;
    border-top: 1px solid var(--border-color);
    background-color: var(--surface-color);
}

.footer-container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 20px;
}

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

.copyright {
    color: var(--text-muted);
    font-size: 0.9rem;
}

.footer-links {
    display: flex;
    gap: 16px;
}

.footer-links a {
    color: var(--text-muted);
    text-decoration: none;
    font-size: 0.9rem;
    transition: var(--transition);
}

.footer-links a:hover {
    color: var(--text-main);
}

.footer-social {
    display: flex;
    gap: 16px;
}

.social-icon {
    color: var(--text-muted);
    transition: var(--transition);
}

.social-icon:hover {
    color: var(--text-main);
}

/* ====================================================
   Responsive Design
   ==================================================== */
@media (max-width: 768px) {
    .hero-title { font-size: 2.5rem; }
    .hero-subtitle { font-size: 1.1rem; }
    
    .audience-grid { grid-template-columns: 1fr; }
    
    .newsletter-form { flex-direction: column; }
    
    .footer-container {
        flex-direction: column;
        text-align: center;
    }
    
    .footer-links, .footer-social {
        justify-content: center;
    }
}