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

:root {
    --color-primary: #6366f1;
    --color-primary-dark: #4f46e5;
    --color-primary-light: #818cf8;
    --color-text: #1f2937;
    --color-text-light: #6b7280;
    --color-background: #ffffff;
    --color-background-alt: #f9fafb;
    --color-border: #e5e7eb;
    --color-success: #10b981;
    --font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    --container-width: 1200px;
    --spacing-xs: 0.5rem;
    --spacing-sm: 1rem;
    --spacing-md: 1.5rem;
    --spacing-lg: 2rem;
    --spacing-xl: 3rem;
    --spacing-2xl: 5rem;
    --border-radius: 8px;
    --border-radius-lg: 12px;
    --shadow-sm: 0 1px 2px 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);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-family);
    font-size: 16px;
    line-height: 1.6;
    color: var(--color-text);
    background-color: var(--color-background);
}

.container {
    max-width: var(--container-width);
    margin: 0 auto;
    padding: 0 var(--spacing-md);
}

/* Typography */
h1, h2, h3, h4 {
    font-weight: 700;
    line-height: 1.2;
    color: var(--color-text);
}

h1 {
    font-size: clamp(2.5rem, 5vw, 3.5rem);
}

h2 {
    font-size: clamp(1.75rem, 3vw, 2.5rem);
    text-align: center;
    margin-bottom: var(--spacing-sm);
}

h3 {
    font-size: 1.25rem;
    margin-bottom: var(--spacing-xs);
}

p {
    color: var(--color-text-light);
}

.section-subtitle {
    text-align: center;
    font-size: 1.125rem;
    margin-bottom: var(--spacing-xl);
}

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 0.75rem 1.5rem;
    font-size: 1rem;
    font-weight: 600;
    text-decoration: none;
    border: none;
    border-radius: var(--border-radius);
    cursor: pointer;
    transition: all 0.2s ease;
}

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

.btn-primary:hover {
    background-color: var(--color-primary-dark);
    transform: translateY(-1px);
    box-shadow: var(--shadow-md);
}

.btn-small {
    padding: 0.5rem 1rem;
    font-size: 0.875rem;
    background-color: var(--color-primary);
    color: white;
}

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

/* Header */
.header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background-color: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--color-border);
    z-index: 1000;
}

.header .container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 72px;
}

.logo {
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--color-text);
}

.header nav {
    display: flex;
    align-items: center;
    gap: var(--spacing-lg);
}

.header nav a {
    color: var(--color-text-light);
    text-decoration: none;
    font-weight: 500;
    transition: color 0.2s ease;
}

.header nav a:hover {
    color: var(--color-text);
}

/* Hero Section */
.hero {
    padding: calc(72px + var(--spacing-2xl)) 0 var(--spacing-2xl);
    text-align: center;
    background: linear-gradient(180deg, var(--color-background-alt) 0%, var(--color-background) 100%);
}

.hero h1 {
    margin-bottom: var(--spacing-md);
}

.highlight {
    color: var(--color-primary);
}

.hero-subtitle {
    font-size: 1.25rem;
    max-width: 700px;
    margin: 0 auto var(--spacing-lg);
    color: var(--color-text-light);
}

.hero-cta {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: var(--spacing-sm);
}

.cta-note {
    font-size: 0.875rem;
    color: var(--color-text-light);
}

/* Problem Section */
.problem {
    padding: var(--spacing-2xl) 0;
    background-color: var(--color-text);
}

.problem-content {
    max-width: 700px;
    margin: 0 auto;
    text-align: center;
}

.problem h2 {
    color: white;
    margin-bottom: var(--spacing-md);
}

.problem p {
    color: rgba(255, 255, 255, 0.8);
    font-size: 1.125rem;
}

/* Features Section */
.features {
    padding: var(--spacing-2xl) 0;
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: var(--spacing-lg);
}

.feature-card {
    padding: var(--spacing-lg);
    border: 1px solid var(--color-border);
    border-radius: var(--border-radius-lg);
    transition: all 0.2s ease;
}

.feature-card:hover {
    border-color: var(--color-primary-light);
    box-shadow: var(--shadow-md);
}

.feature-icon {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 48px;
    height: 48px;
    background-color: var(--color-background-alt);
    border-radius: var(--border-radius);
    margin-bottom: var(--spacing-sm);
    color: var(--color-primary);
}

.feature-card h3 {
    color: var(--color-text);
}

.feature-card p {
    font-size: 0.9375rem;
}

/* How It Works Section */
.how-it-works {
    padding: var(--spacing-2xl) 0;
    background-color: var(--color-background-alt);
}

.steps {
    max-width: 700px;
    margin: 0 auto;
}

.step {
    display: flex;
    gap: var(--spacing-md);
    margin-bottom: var(--spacing-lg);
}

.step:last-child {
    margin-bottom: 0;
}

.step-number {
    flex-shrink: 0;
    display: flex;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
    background-color: var(--color-primary);
    color: white;
    font-weight: 700;
    border-radius: 50%;
}

.step-content h3 {
    margin-bottom: var(--spacing-xs);
}

/* Signup Section */
.signup {
    padding: var(--spacing-2xl) 0;
}

.signup-content {
    max-width: 600px;
    margin: 0 auto;
    text-align: center;
}

.signup h2 {
    margin-bottom: var(--spacing-sm);
}

.signup > .container > .signup-content > p {
    margin-bottom: var(--spacing-lg);
}

.signup-form {
    margin-top: var(--spacing-lg);
}

.form-group {
    display: flex;
    gap: var(--spacing-sm);
    max-width: 480px;
    margin: 0 auto;
}

.form-group input {
    flex: 1;
    padding: 0.875rem 1rem;
    font-size: 1rem;
    border: 1px solid var(--color-border);
    border-radius: var(--border-radius);
    outline: none;
    transition: border-color 0.2s ease;
}

.form-group input:focus {
    border-color: var(--color-primary);
}

.form-group input::placeholder {
    color: var(--color-text-light);
}

.form-note {
    margin-top: var(--spacing-sm);
    font-size: 0.875rem;
    color: var(--color-text-light);
}

.success-message {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-sm);
    padding: var(--spacing-md);
    background-color: #ecfdf5;
    border-radius: var(--border-radius);
    color: var(--color-success);
}

.success-message svg {
    flex-shrink: 0;
}

.success-message p {
    color: var(--color-success);
    font-weight: 500;
}

/* Footer */
.footer {
    padding: var(--spacing-lg) 0;
    border-top: 1px solid var(--color-border);
    text-align: center;
}

.footer p {
    font-size: 0.875rem;
}

/* Responsive */
@media (max-width: 768px) {
    .header nav {
        gap: var(--spacing-sm);
    }

    .header nav a:not(.btn) {
        display: none;
    }

    .form-group {
        flex-direction: column;
    }

    .form-group button {
        width: 100%;
    }

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

    .step {
        flex-direction: column;
        text-align: center;
    }

    .step-number {
        margin: 0 auto;
    }
}