:root {
    --bg-light: #ffffff;
    --bg-dark: #0a0a0a;
    --text-light: #000000;
    --text-dark: #ffffff;
    --accent: #ffd700;
    --accent-hover: #ffed4e;
    --border-light: #f0f0f0;
    --border-dark: #1a1a1a;
    --secondary-light: #f8f8f8;
    --secondary-dark: #121212;
    --shadow-light: 0 18px 60px rgba(0, 0, 0, 0.08);
    --shadow-dark: 0 18px 60px rgba(0, 0, 0, 0.36);
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "Helvetica Neue", sans-serif;
    background-color: var(--bg-light);
    color: var(--text-light);
    line-height: 1.65;
    overflow-x: hidden;
    position: relative;
    transition: background-color 0.3s ease, color 0.3s ease;
}

body::before {
    content: "";
    position: fixed;
    inset: 0;
    pointer-events: none;
    background:
        radial-gradient(circle at 50% 12%, rgba(255, 215, 0, 0.12), transparent 28%),
        radial-gradient(circle at 10% 28%, rgba(255, 215, 0, 0.06), transparent 22%),
        radial-gradient(circle at 88% 24%, rgba(255, 215, 0, 0.08), transparent 26%);
    opacity: 0.55;
    z-index: 0;
}

body.dark-mode {
    background-color: var(--bg-dark);
    color: var(--text-dark);
}

body.dark-mode::before {
    background:
        radial-gradient(circle at 50% 12%, rgba(255, 215, 0, 0.16), transparent 28%),
        radial-gradient(circle at 10% 28%, rgba(255, 215, 0, 0.08), transparent 22%),
        radial-gradient(circle at 88% 24%, rgba(255, 215, 0, 0.1), transparent 26%);
    opacity: 0.4;
}

a {
    color: inherit;
}

header,
main,
footer {
    position: relative;
    z-index: 1;
}

header {
    position: sticky;
    top: 0;
    z-index: 1000;
    background-color: rgba(255, 255, 255, 0.95);
    border-bottom: 1px solid var(--border-light);
    backdrop-filter: blur(10px);
}

body.dark-mode header {
    background-color: rgba(10, 10, 10, 0.95);
    border-bottom-color: var(--border-dark);
}

nav {
    max-width: 1200px;
    margin: 0 auto;
    padding: 1.5rem 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 1rem;
}

.brand {
    text-decoration: none;
    font-size: 1.5rem;
    font-weight: 700;
    letter-spacing: -0.5px;
    transition: transform 0.3s ease;
}

.brand:hover {
    transform: translateY(-1px);
}

.brand span {
    color: var(--accent);
}

.nav-links {
    display: flex;
    align-items: center;
    gap: 1.5rem;
    flex-wrap: wrap;
}

.nav-links a {
    color: var(--text-light);
    text-decoration: none;
    font-weight: 500;
    font-size: 0.95rem;
    transition: all 0.3s ease;
    position: relative;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

body.dark-mode .nav-links a {
    color: var(--text-dark);
}

.nav-links a::after {
    content: "";
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 0;
    height: 2px;
    background-color: var(--accent);
    transition: width 0.3s ease;
}

.nav-links a:hover::after,
.nav-links a:focus-visible::after {
    width: 100%;
}

.nav-links a:hover,
.nav-links a:focus-visible {
    color: var(--accent);
    outline: none;
}

.theme-toggle {
    background: none;
    border: 1px solid var(--text-light);
    color: var(--text-light);
    padding: 0.6rem 1.2rem;
    cursor: pointer;
    border-radius: 4px;
    font-size: 0.9rem;
    font-weight: 500;
    transition: all 0.3s ease;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

body.dark-mode .theme-toggle {
    border-color: var(--text-dark);
    color: var(--text-dark);
}

.theme-toggle:hover,
.theme-toggle:focus-visible {
    background-color: var(--accent);
    border-color: var(--accent);
    color: var(--text-light);
    outline: none;
}

main {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 2rem 2rem;
    position: relative;
}

.hero {
    min-height: 42vh;
    padding: 5rem 0 3.25rem;
    position: relative;
    text-align: center;
    display: flex;
    flex-direction: column;
    justify-content: center;
}

.hero::before {
    content: "";
    position: absolute;
    inset: 6% -8% auto;
    height: 68%;
    background:
        radial-gradient(circle at 50% 24%, rgba(255, 215, 0, 0.18), transparent 38%),
        radial-gradient(circle at 12% 58%, rgba(255, 215, 0, 0.08), transparent 30%),
        radial-gradient(circle at 88% 62%, rgba(255, 215, 0, 0.1), transparent 32%);
    filter: blur(10px);
    pointer-events: none;
}

.kicker {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    text-transform: uppercase;
    letter-spacing: 0.2em;
    font-size: 0.78rem;
    font-weight: 800;
    color: rgba(0, 0, 0, 0.55);
    margin: 0 auto 1rem;
}

body.dark-mode .kicker {
    color: rgba(255, 255, 255, 0.62);
}

.kicker::before {
    content: "";
    width: 2.75rem;
    height: 2px;
    background: var(--accent);
}

h1 {
    margin: 0;
    font-size: clamp(2.5rem, 5vw, 4.5rem);
    line-height: 1.02;
    letter-spacing: -0.06em;
}

.meta {
    margin: 1rem auto 0;
    color: rgba(0, 0, 0, 0.65);
    max-width: 44rem;
}

body.dark-mode .meta {
    color: rgba(255, 255, 255, 0.7);
}

.content {
    display: grid;
    gap: 1rem;
    margin-top: 0.5rem;
}

.content section {
    padding: 1.6rem 1.65rem;
    border: 1px solid var(--border-light);
    border-radius: 18px;
    background: linear-gradient(180deg, rgba(255, 255, 255, 0.88) 0%, rgba(248, 248, 248, 0.92) 100%);
    box-shadow: var(--shadow-light);
}

body.dark-mode .content section {
    border-color: var(--border-dark);
    background: linear-gradient(180deg, rgba(18, 18, 18, 0.96) 0%, rgba(16, 16, 16, 0.96) 100%);
    box-shadow: var(--shadow-dark);
}

h2 {
    margin: 0 0 0.85rem;
    font-size: 1.18rem;
    line-height: 1.2;
    letter-spacing: -0.04em;
}

p {
    margin: 0.65rem 0;
}

ul {
    margin: 0.75rem 0 0;
    padding-left: 1.2rem;
}

li {
    margin: 0.35rem 0;
}

.note {
    opacity: 0.76;
}

footer {
    background-color: var(--secondary-light);
    border-top: 1px solid var(--border-light);
    margin-top: 4rem;
    padding: 3rem 2rem;
}

body.dark-mode footer {
    background-color: var(--secondary-dark);
    border-top-color: var(--border-dark);
}

.footer-card {
    max-width: 1200px;
    margin: 0 auto;
    text-align: center;
}

.footer-links {
    display: flex;
    justify-content: center;
    gap: 1rem 1.5rem;
    margin-bottom: 2rem;
    flex-wrap: wrap;
}

.footer-links a {
    color: var(--text-light);
    text-decoration: none;
    font-size: 0.9rem;
    opacity: 0.82;
    transition: color 0.3s ease, opacity 0.3s ease;
}

body.dark-mode .footer-links a {
    color: var(--text-dark);
}

.footer-links a:hover,
.footer-links a:focus-visible {
    color: var(--accent);
    opacity: 1;
    outline: none;
}

.footer-copy {
    opacity: 0.7;
    margin: 0;
    font-size: 0.9rem;
}

@media (max-width: 900px) {
    nav {
        flex-wrap: wrap;
    }

    .nav-links {
        gap: 1rem;
    }
}

@media (max-width: 720px) {
    nav {
        padding: 1.25rem 1rem;
    }

    main {
        padding: 0 1rem 1.5rem;
    }

    .hero {
        min-height: auto;
        padding: 3.5rem 0 2.4rem;
    }

    .content section {
        padding: 1.3rem 1.15rem;
        border-radius: 16px;
    }

    footer {
        padding: 2.5rem 1rem;
    }
}