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

:root {
    --color-primary: #4f46e5;
    --color-primary-dark: #4338ca;
    --color-text: #1f2937;
    --color-text-light: #6b7280;
    --color-bg: #ffffff;
    --color-bg-alt: #f9fafb;
    --color-border: #e5e7eb;
    --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    --max-width: 800px;
    --spacing-xs: 0.5rem;
    --spacing-sm: 1rem;
    --spacing-md: 1.5rem;
    --spacing-lg: 2rem;
    --spacing-xl: 3rem;
    --spacing-2xl: 4rem;
}

html {
    font-size: 16px;
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-sans);
    color: var(--color-text);
    background: var(--color-bg);
    line-height: 1.7;
    -webkit-font-smoothing: antialiased;
}

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

.header {
    background: var(--color-bg);
    border-bottom: 1px solid var(--color-border);
    padding: var(--spacing-sm) 0;
    position: sticky;
    top: 0;
    z-index: 100;
}

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

.logo {
    font-weight: 600;
    font-size: 1.1rem;
    color: var(--color-text);
    text-decoration: none;
}

.hero {
    background: linear-gradient(135deg, #3730a3 0%, #4f46e5 100%);
    color: white;
    padding: var(--spacing-2xl) 0;
    text-align: center;
}

.hero h1 {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: var(--spacing-sm);
    line-height: 1.2;
}

.hero-subtitle {
    font-size: 1.25rem;
    opacity: 0.9;
}

.section {
    padding: var(--spacing-xl) 0;
}

.answer-box {
    background: #eef2ff;
    border-left: 4px solid var(--color-primary);
    padding: var(--spacing-md);
    border-radius: 0 8px 8px 0;
    font-size: 1.1rem;
}

.answer-box p {
    margin: 0;
}

.answer-box a {
    color: var(--color-primary);
}

.content-section {
    margin-bottom: var(--spacing-2xl);
}

.content-section h2 {
    font-size: 1.75rem;
    font-weight: 700;
    margin-bottom: var(--spacing-md);
    color: var(--color-text);
}

.content-section h3 {
    font-size: 1.1rem;
    font-weight: 600;
    margin-top: var(--spacing-md);
    margin-bottom: var(--spacing-sm);
    color: var(--color-text);
}

.content-section p {
    margin-bottom: var(--spacing-md);
    color: var(--color-text);
}

.content-section a {
    color: var(--color-primary);
    text-decoration: underline;
    text-underline-offset: 2px;
}

/* Level Cards */
.level-cards {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: var(--spacing-sm);
    margin-top: var(--spacing-lg);
}

.level-card {
    background: var(--color-bg-alt);
    border: 1px solid var(--color-border);
    border-radius: 12px;
    padding: var(--spacing-md);
    text-align: center;
}

.level-badge {
    display: inline-block;
    font-size: 0.7rem;
    font-weight: 600;
    padding: 4px 10px;
    border-radius: 12px;
    margin-bottom: var(--spacing-sm);
    text-transform: uppercase;
}

.level-1 { background: #dcfce7; color: #166534; }
.level-2 { background: #fef3c7; color: #92400e; }
.level-3 { background: #dbeafe; color: #1e40af; }
.level-4 { background: #f3e8ff; color: #6b21a8; }

.level-card h3 {
    margin: 0 0 var(--spacing-xs);
    font-size: 1rem;
}

.level-card p {
    font-size: 0.85rem;
    color: var(--color-text-light);
    margin-bottom: var(--spacing-sm);
}

.level-time {
    font-size: 0.75rem;
    color: var(--color-text-light);
}

/* Learn Block */
.learn-block {
    background: var(--color-bg-alt);
    border-radius: 12px;
    padding: var(--spacing-md);
    margin: var(--spacing-md) 0;
}

.learn-block h3 {
    margin-top: 0;
}

.resource-list {
    list-style: none;
    padding: 0;
    margin: 0 0 var(--spacing-md);
}

.resource-list li {
    padding: var(--spacing-xs) 0;
    border-bottom: 1px solid var(--color-border);
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: var(--spacing-xs);
}

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

.resource-list a, .resource-list span:first-child {
    font-weight: 500;
}

.resource-meta {
    font-size: 0.8rem;
    color: var(--color-text-light);
}

.action-list {
    list-style: none;
    padding: 0;
    margin: 0;
}

.action-list li {
    padding: var(--spacing-xs) 0;
    padding-left: 24px;
    position: relative;
}

.action-list li::before {
    content: '→';
    position: absolute;
    left: 0;
    color: var(--color-primary);
}

/* Milestone Box */
.milestone-box {
    background: #eef2ff;
    border: 2px dashed var(--color-primary);
    border-radius: 12px;
    padding: var(--spacing-md);
    margin-top: var(--spacing-md);
}

.milestone-label {
    display: block;
    font-weight: 600;
    color: var(--color-primary);
    margin-bottom: var(--spacing-xs);
}

.milestone-box p {
    margin: 0;
    font-size: 0.95rem;
}

/* Resources Grid */
.resources-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: var(--spacing-md);
    margin-top: var(--spacing-lg);
}

.resource-card {
    background: var(--color-bg-alt);
    border: 1px solid var(--color-border);
    border-radius: 12px;
    padding: var(--spacing-md);
}

.resource-type {
    display: inline-block;
    font-size: 0.75rem;
    color: var(--color-text-light);
    margin-bottom: var(--spacing-xs);
}

.resource-card h3 {
    margin: 0 0 var(--spacing-xs);
    font-size: 1rem;
}

.resource-card p {
    font-size: 0.9rem;
    color: var(--color-text-light);
    margin-bottom: var(--spacing-sm);
}

.resource-card a {
    font-size: 0.9rem;
    font-weight: 500;
}

/* FAQ */
.faq-list {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-sm);
}

.faq-item {
    background: var(--color-bg-alt);
    border: 1px solid var(--color-border);
    border-radius: 8px;
    overflow: hidden;
}

.faq-item summary {
    padding: var(--spacing-md);
    font-weight: 600;
    cursor: pointer;
    list-style: none;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.faq-item summary::-webkit-details-marker {
    display: none;
}

.faq-item summary::after {
    content: '+';
    font-size: 1.5rem;
    font-weight: 400;
    color: var(--color-text-light);
    transition: transform 0.2s;
}

.faq-item[open] summary::after {
    transform: rotate(45deg);
}

.faq-item p {
    padding: 0 var(--spacing-md) var(--spacing-md);
    margin: 0;
    color: var(--color-text-light);
}

/* CTA */
.cta-section {
    background: var(--color-bg-alt);
}

.cta-box {
    background: white;
    border: 2px solid var(--color-primary);
    border-radius: 16px;
    padding: var(--spacing-xl);
    text-align: center;
}

.cta-box h2 {
    font-size: 1.75rem;
    margin-bottom: var(--spacing-sm);
}

.cta-box p {
    color: var(--color-text-light);
    margin-bottom: var(--spacing-md);
    max-width: 500px;
    margin-left: auto;
    margin-right: auto;
}

.cta-button {
    display: inline-block;
    background: var(--color-primary);
    color: white;
    font-weight: 600;
    padding: var(--spacing-sm) var(--spacing-lg);
    border-radius: 8px;
    text-decoration: none;
    transition: background 0.2s;
}

.cta-button:hover {
    background: var(--color-primary-dark);
}

.cta-note {
    font-size: 0.85rem;
    color: var(--color-text-light);
    margin-top: var(--spacing-sm);
    margin-bottom: 0 !important;
}

.footer {
    background: var(--color-text);
    color: white;
    padding: var(--spacing-lg) 0;
    text-align: center;
    font-size: 0.9rem;
}

.footer a {
    color: #a5b4fc;
    text-decoration: none;
}

.footer a:hover {
    text-decoration: underline;
}

/* Responsive */
@media (max-width: 640px) {
    .hero h1 {
        font-size: 1.75rem;
    }

    .level-cards {
        grid-template-columns: repeat(2, 1fr);
    }

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

    .resource-list li {
        flex-direction: column;
        align-items: flex-start;
    }

    .cta-box {
        padding: var(--spacing-lg);
    }
}