/* RESET & VARIABLES */
:root {
    --bg-dark: #0f172a;
    --bg-darker: #020617;
    --surface: #1e293b;
    --surface-light: #334155;
    --primary: #6366f1;
    --primary-hover: #4f46e5;
    --secondary: #10b981;
    --text-main: #f8fafc;
    --text-muted: #94a3b8;
    --border: rgba(255, 255, 255, 0.1);
    --glass: rgba(30, 41, 59, 0.7);
    --glow: 0 0 40px rgba(99, 102, 241, 0.2);
}

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

body {
    font-family: 'Inter', sans-serif;
    background-color: var(--bg-dark);
    color: var(--text-main);
    line-height: 1.6;
    overflow-x: hidden;
}

/* TYPOGRAPHY */
h1, h2, h3, h4 {
    line-height: 1.2;
    font-weight: 800;
    letter-spacing: -0.02em;
}

.text-gradient {
    background: linear-gradient(to right, #818cf8, #c084fc);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

/* LAYOUT */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px;
}

/* NAVIGATION */
nav {
    position: fixed;
    top: 0;
    width: 100%;
    background: rgba(15, 23, 42, 0.8);
    backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--border);
    z-index: 100;
    padding: 16px 0;
}

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

.nav-logo {
    font-size: 1.5rem;
    font-weight: 900;
    color: white;
    text-decoration: none;
    letter-spacing: -1px;
}

.nav-logo span {
    color: var(--primary);
}

/* BUTTONS */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 16px 32px;
    border-radius: 12px;
    font-weight: 700;
    font-size: 1.1rem;
    text-decoration: none;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    border: none;
    cursor: pointer;
}

.btn-primary {
    background: var(--primary);
    color: white;
    box-shadow: 0 4px 20px rgba(99, 102, 241, 0.4);
}

.btn-primary:hover {
    background: var(--primary-hover);
    transform: translateY(-2px);
    box-shadow: 0 8px 30px rgba(99, 102, 241, 0.6);
}

.btn-success {
    background: var(--secondary);
    color: white;
    box-shadow: 0 4px 20px rgba(16, 185, 129, 0.3);
}

.btn-success:hover {
    background: #059669;
    transform: translateY(-2px);
    box-shadow: 0 8px 30px rgba(16, 185, 129, 0.5);
}

.btn-large {
    padding: 20px 48px;
    font-size: 1.25rem;
    width: 100%;
    max-width: 400px;
}

/* HERO SECTION */
.hero {
    padding: 160px 0 80px;
    text-align: center;
    position: relative;
    overflow: hidden;
}

.hero::before {
    content: '';
    position: absolute;
    top: -50%;
    left: 50%;
    transform: translateX(-50%);
    width: 800px;
    height: 800px;
    background: radial-gradient(circle, rgba(99, 102, 241, 0.15) 0%, rgba(15, 23, 42, 0) 70%);
    z-index: -1;
}

.hero-badge {
    display: inline-block;
    padding: 8px 16px;
    background: rgba(99, 102, 241, 0.1);
    border: 1px solid rgba(99, 102, 241, 0.3);
    color: #a5b4fc;
    border-radius: 999px;
    font-size: 0.875rem;
    font-weight: 600;
    margin-bottom: 24px;
    letter-spacing: 0.5px;
}

.hero h1 {
    font-size: clamp(2.5rem, 5vw, 4.5rem);
    margin-bottom: 24px;
    max-width: 900px;
    margin-left: auto;
    margin-right: auto;
}

.hero p {
    font-size: clamp(1.1rem, 2vw, 1.35rem);
    color: var(--text-muted);
    max-width: 700px;
    margin: 0 auto 40px;
}

/* OPT-IN SECTION */
.optin-section {
    padding: 60px 0;
    background: var(--bg-darker);
    border-top: 1px solid var(--border);
    border-bottom: 1px solid var(--border);
}

.optin-box {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 24px;
    padding: 48px;
    position: relative;
    box-shadow: var(--glow);
    max-width: 800px;
    margin: 0 auto;
    text-align: center;
}

.optin-form {
    display: flex;
    gap: 16px;
    margin: 32px auto 0;
    max-width: 500px;
}

.optin-input {
    flex: 1;
    background: var(--bg-dark);
    border: 1px solid var(--border);
    padding: 16px 24px;
    border-radius: 12px;
    color: white;
    font-family: inherit;
    font-size: 1rem;
    transition: border-color 0.2s;
}

.optin-input:focus {
    outline: none;
    border-color: var(--primary);
}

.optin-btn {
    white-space: nowrap;
}

#success-message {
    background: rgba(16, 185, 129, 0.1);
    border: 1px solid rgba(16, 185, 129, 0.3);
    color: #34d399;
    padding: 16px;
    border-radius: 12px;
    margin-top: 24px;
    font-weight: 500;
    display: none;
}

/* PROBLEMS GRID */
.problems {
    padding: 100px 0;
}

.section-header {
    text-align: center;
    margin-bottom: 64px;
}

.section-header h2 {
    font-size: 2.5rem;
    margin-bottom: 16px;
}

.problems-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 24px;
}

.problem-card {
    background: var(--surface);
    border: 1px solid var(--border);
    padding: 32px;
    border-radius: 16px;
    transition: transform 0.3s;
}

.problem-card:hover {
    transform: translateY(-5px);
    border-color: rgba(99, 102, 241, 0.3);
}

.problem-icon {
    font-size: 2rem;
    margin-bottom: 20px;
    display: inline-block;
    background: rgba(239, 68, 68, 0.1);
    padding: 12px;
    border-radius: 12px;
}

/* COST COMPARISON (THE FIX) */
.comparison {
    padding: 100px 0;
    background: var(--bg-darker);
    border-top: 1px solid var(--border);
}

.comparison-wrapper {
    display: flex;
    gap: 32px;
    max-width: 1000px;
    margin: 0 auto;
}

.comp-column {
    flex: 1;
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 24px;
    padding: 40px;
    position: relative;
    overflow: hidden;
}

.comp-column.ai-stack {
    background: linear-gradient(180deg, var(--surface) 0%, rgba(99, 102, 241, 0.1) 100%);
    border-color: rgba(99, 102, 241, 0.3);
    box-shadow: 0 20px 40px rgba(99, 102, 241, 0.1);
}

.comp-column.ai-stack::before {
    content: 'BEST VALUE';
    position: absolute;
    top: 24px;
    right: -32px;
    background: var(--secondary);
    color: white;
    padding: 6px 40px;
    font-size: 0.75rem;
    font-weight: 800;
    transform: rotate(45deg);
    letter-spacing: 1px;
}

.comp-header {
    text-align: center;
    margin-bottom: 40px;
    padding-bottom: 24px;
    border-bottom: 1px solid var(--border);
}

.comp-header h3 {
    font-size: 1.5rem;
    margin-bottom: 8px;
    color: var(--text-muted);
}

.comp-header .price {
    font-size: 3rem;
    font-weight: 900;
    color: white;
}

.comp-header .price span {
    font-size: 1rem;
    color: var(--text-muted);
    font-weight: 500;
}

.comp-list {
    list-style: none;
}

.comp-list li {
    display: flex;
    justify-content: space-between;
    padding: 16px 0;
    border-bottom: 1px dashed rgba(255, 255, 255, 0.05);
    font-size: 1.05rem;
}

.comp-list li:last-child {
    border-bottom: none;
}

.comp-column.traditional .comp-list li span:last-child {
    color: #ef4444;
    font-family: monospace;
    font-size: 1.1rem;
}

.comp-column.ai-stack .comp-list li span:last-child {
    color: var(--secondary);
    font-weight: 700;
}

.comp-column.ai-stack .comp-list li::before {
    content: '✓';
    color: var(--secondary);
    margin-right: 12px;
    font-weight: 900;
}

/* CTA SECTION */
.cta-bottom {
    padding: 100px 0;
    text-align: center;
}

/* FOOTER */
footer {
    padding: 40px 0;
    text-align: center;
    border-top: 1px solid var(--border);
    background: var(--bg-darker);
    color: var(--text-muted);
    font-size: 0.9rem;
}

@media (max-width: 768px) {
    .comparison-wrapper {
        flex-direction: column;
    }
    
    .optin-form {
        flex-direction: column;
    }
    
    .btn-large {
        width: 100%;
    }
}