:root {
    --primary-blue: #2563eb;
    --primary-hover: #1d4ed8;
    --bg-color: #f8fafc;
    --card-bg: #ffffff;
    --dark-text: #0f172a;
    --gray-text: #64748b;
    --light-border: #e2e8f0;
    --sidebar-bg: #ffffff;
    --shadow-sm: 0 1px 3px rgba(0,0,0,0.05);
    --shadow-md: 0 4px 6px -1px rgba(0,0,0,0.05), 0 2px 4px -1px rgba(0,0,0,0.03);
    --shadow-hover: 0 10px 15px -3px rgba(0,0,0,0.08), 0 4px 6px -2px rgba(0,0,0,0.04);
}

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

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
    line-height: 1.6;
    color: var(--dark-text);
    background-color: var(--bg-color);
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

.container {
    max-width: 1280px;
    margin: 0 auto;
    padding: 0 24px;
    width: 100%;
}

header {
    background: rgba(255, 255, 255, 0.8);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    position: sticky;
    top: 0;
    z-index: 1000;
    border-bottom: 1px solid var(--light-border);
}

nav {
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 72px;
    gap: 2rem;
}

.logo {
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--dark-text);
    text-decoration: none;
    display: flex;
    align-items: center;
    gap: 0.75rem;
    flex-shrink: 0;
}

.search-container {
    position: relative;
    flex: 1;
    max-width: 480px;
}

.search-input {
    width: 100%;
    padding: 0.6rem 1rem 0.6rem 2.5rem;
    border: 1px solid var(--light-border);
    border-radius: 8px;
    font-size: 0.95rem;
    font-family: inherit;
    transition: all 0.2s ease;
    background: var(--bg-color);
    color: var(--dark-text);
}

.search-input:focus {
    outline: none;
    border-color: var(--primary-blue);
    background: var(--card-bg);
    box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.1);
}

.search-icon {
    position: absolute;
    left: 0.8rem;
    top: 50%;
    transform: translateY(-50%);
    color: var(--gray-text);
}

.main-layout {
    display: grid;
    grid-template-columns: 260px 1fr;
    gap: 2.5rem;
    margin-top: 2rem;
    flex: 1;
}

.sidebar {
    background: var(--sidebar-bg);
    padding: 1.5rem;
    border-radius: 12px;
    border: 1px solid var(--light-border);
    box-shadow: var(--shadow-sm);
    height: fit-content;
    position: sticky;
    top: 96px;
}

.sidebar h3 {
    font-size: 0.85rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--gray-text);
    margin-bottom: 1rem;
}

.sidebar ul {
    list-style: none;
}

.sidebar li {
    margin-bottom: 0.25rem;
}

.sidebar .divider {
    font-size: 0.75rem;
    text-transform: uppercase;
    color: var(--gray-text);
    font-weight: 600;
    margin: 1.25rem 0 0.5rem 0.5rem;
}

.sidebar a {
    color: var(--dark-text);
    text-decoration: none;
    font-size: 0.95rem;
    display: block;
    padding: 0.6rem 0.75rem;
    border-radius: 6px;
    transition: all 0.2s ease;
    font-weight: 500;
}

.sidebar a:hover {
    background: var(--bg-color);
    color: var(--primary-blue);
}

.sidebar a.active {
    background: var(--primary-blue);
    color: white;
}

.view-section {
    animation: fadeIn 0.3s ease-in-out;
}

.hidden {
    display: none !important;
}

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

.view-header {
    margin-bottom: 2rem;
    padding-bottom: 1rem;
    border-bottom: 1px solid var(--light-border);
}

.view-header h2 {
    font-size: 1.8rem;
    color: var(--dark-text);
    margin-bottom: 0.5rem;
}

.view-header p {
    color: var(--gray-text);
    font-size: 1.05rem;
}

.hero {
    text-align: center;
    padding: 3rem 0;
}

.hero h1 {
    font-size: 3rem;
    font-weight: 800;
    letter-spacing: -0.02em;
    color: var(--dark-text);
    margin-bottom: 1rem;
}

.hero p {
    font-size: 1.15rem;
    color: var(--gray-text);
    max-width: 700px;
    margin: 0 auto;
}

.cards-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 1.5rem;
    margin-bottom: 2.5rem;
}

.card {
    background: var(--card-bg);
    border-radius: 12px;
    padding: 1.5rem;
    border: 1px solid var(--light-border);
    box-shadow: var(--shadow-sm);
}

.card-icon {
    font-size: 2rem;
    margin-bottom: 1rem;
}

.card h3 {
    font-size: 1.2rem;
    margin-bottom: 0.5rem;
}

.card p {
    color: var(--gray-text);
    font-size: 0.95rem;
}

.quick-start-box {
    background: var(--card-bg);
    border-radius: 12px;
    padding: 2rem;
    border: 1px solid var(--primary-blue);
    box-shadow: var(--shadow-sm);
}

.quick-start-box h2 {
    margin-bottom: 1.5rem;
}

.roadmap-list {
    margin-left: 1.2rem;
    margin-bottom: 1.5rem;
}

.roadmap-list li {
    margin-bottom: 0.75rem;
    color: var(--dark-text);
}

.hint {
    color: var(--primary-blue);
    font-weight: 600;
}

.resources-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
    gap: 1.25rem;
}

.resource-card {
    background: var(--card-bg);
    border-radius: 10px;
    padding: 1.25rem;
    border: 1px solid var(--light-border);
    box-shadow: var(--shadow-sm);
    transition: all 0.2s ease;
    display: flex;
    flex-direction: column;
}

.resource-card:hover {
    transform: translateY(-3px);
    box-shadow: var(--shadow-hover);
    border-color: var(--primary-blue);
}

.resource-card h4 {
    font-size: 1.05rem;
    color: var(--dark-text);
    margin-bottom: 0.75rem;
    line-height: 1.4;
}

.resource-meta {
    margin-top: auto;
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding-top: 1rem;
    border-top: 1px solid var(--light-border);
}

.resource-domain {
    font-size: 0.8rem;
    color: var(--gray-text);
    display: flex;
    align-items: center;
    gap: 0.25rem;
}

.resource-link {
    font-size: 0.85rem;
    color: var(--primary-blue);
    text-decoration: none;
    font-weight: 600;
}

.resource-link:hover {
    color: var(--primary-hover);
    text-decoration: underline;
}

footer {
    text-align: center;
    padding: 3rem 0 2rem;
    margin-top: auto;
}

.footer-content {
    border-top: 1px solid var(--light-border);
    padding-top: 2rem;
    color: var(--dark-text);
    font-weight: 500;
}

.footer-content .sub-text {
    color: var(--gray-text);
    font-weight: 400;
    font-size: 0.9rem;
    margin-top: 0.25rem;
}

@media (max-width: 900px) {
    .main-layout {
        grid-template-columns: 1fr;
    }
    .sidebar {
        position: static;
    }
    nav {
        flex-direction: column;
        height: auto;
        padding: 1rem 0;
        gap: 1rem;
    }
    .search-container {
        max-width: 100%;
    }
}

.legal-container {
    max-width: 800px;
    margin: 40px auto;
    padding: 40px;
    background: var(--card-bg);
    border: 1px solid var(--light-border);
    border-radius: 12px;
    box-shadow: var(--shadow-sm);
}
.legal-container h1 { font-size: 2.2rem; margin-bottom: 1.5rem; color: var(--dark-text); }
.legal-container h2 { font-size: 1.4rem; margin-top: 2rem; margin-bottom: 1rem; color: var(--dark-text); border-left: 4px solid var(--primary-blue); padding-left: 15px; }
.legal-container p, .legal-container li { color: var(--gray-text); line-height: 1.8; margin-bottom: 1rem; }
.back-home { display: inline-block; margin-bottom: 20px; color: var(--primary-blue); text-decoration: none; font-weight: 600; }