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

/* === THEME VARIABLES === */
:root {
    --primary-color: #0175c2;
    --primary-dark: #015a94;
    --accent-color: #13b9fd;
    --text-primary: #1a1a1a;
    --text-secondary: #666;
    --text-light: #888;
    --bg-primary: #ffffff;
    --bg-secondary: #f8fafc;
    --bg-card: #ffffff;
    --border-color: #e2e8f0;
    --shadow-light: 0 1px 3px rgba(0, 0, 0, 0.12), 0 1px 2px rgba(0, 0, 0, 0.24);
    --shadow-medium: 0 4px 6px rgba(0, 0, 0, 0.07), 0 1px 3px rgba(0, 0, 0, 0.1);
    --shadow-heavy: 0 10px 25px rgba(0, 0, 0, 0.1), 0 4px 10px rgba(0, 0, 0, 0.06);
    --gradient-primary: linear-gradient(135deg, #0175c2 0%, #13b9fd 100%);
    --gradient-secondary: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, sans-serif;
    line-height: 1.6;
    color: var(--text-primary);
    background: var(--bg-secondary);
    overflow-x: hidden;
}

/* === HEADER === */
header {
    background: var(--gradient-primary);
    color: white;
    padding: 2rem 0;
    position: relative;
    overflow: hidden;
}

header::before {
    content: '';
    position: absolute;
    top: -50%;
    right: -50%;
    width: 200%;
    height: 200%;
    background: radial-gradient(circle, rgba(255,255,255,0.1) 0%, transparent 70%);
    animation: float 6s ease-in-out infinite;
}

@keyframes float {
    0%, 100% { transform: translateY(0px) rotate(0deg); }
    50% { transform: translateY(-20px) rotate(5deg); }
}

.header-content {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 2rem;
    position: relative;
    z-index: 2;
}

.logo {
    display: flex;
    align-items: center;
    gap: 1rem;
    margin-bottom: 1.5rem;
}

.logo-icon {
    width: 80px;
    height: 80px;
    background: rgba(255, 255, 255, 0.15);
    border-radius: 20px;
    display: flex;
    align-items: center;
    justify-content: center;
    backdrop-filter: blur(15px);
    border: 2px solid rgba(255, 255, 255, 0.2);
}

.logo-icon img {
    width: 60px;
    height: 60px;
    border-radius: 12px;
}

.logo h1 {
    font-size: 2.5rem;
    font-weight: 700;
    margin: 0;
}

.subtitle {
    font-size: 1.2rem;
    opacity: 0.9;
    margin-bottom: 0.5rem;
}

.last-updated {
    font-size: 1rem;
    opacity: 0.8;
    background: rgba(255, 255, 255, 0.1);
    display: inline-block;
    padding: 0.5rem 1rem;
    border-radius: 20px;
    backdrop-filter: blur(5px);
}

/* === MAIN CONTENT === */
main {
    max-width: 1000px;
    margin: -2rem auto 0;
    padding: 0 2rem 4rem;
    position: relative;
    z-index: 3;
}

.intro {
    background: var(--bg-card);
    border-radius: 20px;
    padding: 2.5rem;
    margin-bottom: 3rem;
    box-shadow: var(--shadow-heavy);
    border: 1px solid var(--border-color);
    position: relative;
    overflow: hidden;
    text-align: center;
}

.intro::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: var(--gradient-primary);
}

.intro h2 {
    color: var(--primary-color);
    font-size: 1.8rem;
    margin-bottom: 1rem;
}

.intro p {
    font-size: 1.1rem;
    color: var(--text-secondary);
    max-width: 600px;
    margin: 0 auto;
    line-height: 1.7;
}

.content-section {
    background: var(--bg-card);
    border-radius: 12px;
    padding: 2rem;
    margin-bottom: 1.5rem;
    box-shadow: var(--shadow-light);
    border: 1px solid var(--border-color);
    transition: all 0.3s ease;
}

.content-section:hover {
    box-shadow: var(--shadow-medium);
}

.content-section h2 {
    color: var(--primary-color);
    font-size: 1.5rem;
    margin-bottom: 1rem;
    display: flex;
    align-items: center;
    gap: 0.8rem;
}

.content-section h3 {
    color: var(--primary-dark);
    font-size: 1.2rem;
    margin: 1.5rem 0 0.8rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.content-section p,
.content-section li {
    color: var(--text-secondary);
    line-height: 1.6;
}

.content-section ul,
.content-section ol {
    margin: 1rem 0;
    padding-left: 0;
    list-style: none;
}

.content-section li {
    margin: 0.8rem 0;
    padding-left: 2rem;
    position: relative;
}

.content-section ul li::before {
    content: '•';
    color: var(--accent-color);
    font-size: 1.5rem;
    position: absolute;
    left: 0.5rem;
    top: -0.1rem;
}

.content-section ol {
    counter-reset: item;
}

.content-section ol li::before {
    content: counter(item);
    counter-increment: item;
    background: var(--gradient-primary);
    color: white;
    width: 24px;
    height: 24px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 0.8rem;
    position: absolute;
    left: 0;
    top: 0.2rem;
}

.highlight-box {
    background: linear-gradient(135deg, rgba(1, 117, 194, 0.1), rgba(19, 185, 253, 0.1));
    border: 1px solid rgba(1, 117, 194, 0.2);
    border-radius: 12px;
    padding: 1.5rem;
    margin: 1.5rem 0;
    position: relative;
}


a {
    color: var(--primary-color);
    text-decoration: none;
    transition: all 0.3s ease;
    position: relative;
}

a:hover {
    color: var(--primary-dark);
}

a::after {
    content: '';
    position: absolute;
    bottom: -2px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--gradient-primary);
    transition: width 0.3s ease;
}

a:hover::after {
    width: 100%;
}

code {
    background: rgba(1, 117, 194, 0.1);
    color: var(--primary-dark);
    padding: 0.2rem 0.4rem;
    border-radius: 4px;
    font-family: 'Monaco', 'Menlo', 'Ubuntu Mono', monospace;
    font-size: 0.9rem;
}

footer {
    background: var(--text-primary);
    color: white;
    padding: 3rem 0 2rem;
    margin-top: 4rem;
}

.footer-content {
    max-width: 1000px;
    margin: 0 auto;
    padding: 0 2rem;
    text-align: center;
}

.footer-content p {
    opacity: 0.8;
    margin-bottom: 1rem;
}

.back-to-top {
    position: fixed;
    bottom: 2rem;
    right: 2rem;
    width: 50px;
    height: 50px;
    background: var(--gradient-primary);
    color: white;
    border: none;
    border-radius: 50%;
    cursor: pointer;
    box-shadow: var(--shadow-medium);
    transition: all 0.3s ease;
    opacity: 0;
    transform: translateY(100px);
    z-index: 1000;
}

.back-to-top.visible {
    opacity: 1;
    transform: translateY(0);
}

.back-to-top:hover {
    transform: translateY(-3px);
    box-shadow: var(--shadow-heavy);
}

@media (max-width: 768px) {
    .header-content {
        padding: 0 1rem;
        text-align: center;
    }

    .logo {
        justify-content: center;
    }

    .logo h1 {
        font-size: 2rem;
    }

    main {
        padding: 0 1rem 2rem;
    }

    .content-section,
    .intro {
        padding: 1.5rem;
    }

    .content-section h2 {
        font-size: 1.5rem;
    }

    .intro h2 {
        font-size: 1.7rem;
    }
}

.fade-in {
    opacity: 0;
    transform: translateY(30px);
    transition: all 0.6s ease;
}

.fade-in.visible {
    opacity: 1;
    transform: translateY(0);
}