/* ===== 全局重置与基础样式 ===== */
*, *::before, *::after {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    --primary: #eab308;
    --primary-dark: #ca8a04;
    --bg-dark: #0a1628;
    --bg-dark-2: #111e3a;
    --bg-dark-card: rgba(17, 30, 58, 0.7);
    --bg-light: #f8fafc;
    --bg-light-2: #e2e8f0;
    --text-dark: #0f172a;
    --text-light: #f1f5f9;
    --text-muted: #94a3b8;
    --glass-bg: rgba(255, 255, 255, 0.06);
    --glass-border: rgba(255, 255, 255, 0.12);
    --shadow: 0 8px 32px rgba(0, 0, 0, 0.3);
    --radius: 16px;
    --radius-sm: 10px;
    --transition: 0.35s cubic-bezier(0.4, 0, 0.2, 1);
    --font: 'Segoe UI', system-ui, -apple-system, sans-serif;
}

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

body {
    font-family: var(--font);
    background: var(--bg-dark);
    color: var(--text-light);
    line-height: 1.65;
    overflow-x: hidden;
    transition: background var(--transition), color var(--transition);
}

/* 暗色模式默认（已为暗色） */
body.light-mode {
    background: var(--bg-light);
    color: var(--text-dark);
}

a {
    color: var(--primary);
    text-decoration: none;
    transition: color var(--transition);
}

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

img, svg {
    max-width: 100%;
    display: block;
}

ul, ol {
    list-style: none;
}

h1, h2, h3, h4 {
    line-height: 1.3;
    letter-spacing: 0.01em;
}

h1 {
    font-size: clamp(1.8rem, 5vw, 3.2rem);
}

h2 {
    font-size: clamp(1.5rem, 4vw, 2.4rem);
    margin-bottom: 1.2rem;
}

h3 {
    font-size: clamp(1.1rem, 2.5vw, 1.4rem);
    margin-bottom: 0.6rem;
}

p {
    margin-bottom: 1rem;
    color: var(--text-muted);
}

.light-mode p {
    color: #334155;
}

section {
    padding: 4rem 1.5rem;
    max-width: 1200px;
    margin: 0 auto;
}

/* ===== 滚动动画基类 ===== */
.fade-in {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.7s ease, transform 0.7s ease;
}

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

/* ===== 按钮 ===== */
.btn-primary, .btn-secondary {
    display: inline-block;
    padding: 0.85rem 2.2rem;
    border-radius: 50px;
    font-weight: 700;
    font-size: 1rem;
    text-align: center;
    transition: all var(--transition);
    border: 2px solid transparent;
    cursor: pointer;
}

.btn-primary {
    background: linear-gradient(135deg, var(--primary), #f59e0b);
    color: #0a1628;
    box-shadow: 0 4px 18px rgba(234, 179, 8, 0.35);
}

.btn-primary:hover {
    transform: translateY(-3px) scale(1.02);
    box-shadow: 0 8px 28px rgba(234, 179, 8, 0.5);
    background: linear-gradient(135deg, #fbbf24, var(--primary));
}

.btn-secondary {
    background: transparent;
    border-color: var(--primary);
    color: var(--primary);
}

.btn-secondary:hover {
    background: var(--primary);
    color: #0a1628;
    transform: translateY(-3px);
}

.light-mode .btn-secondary {
    color: var(--primary-dark);
    border-color: var(--primary-dark);
}

.light-mode .btn-secondary:hover {
    background: var(--primary-dark);
    color: #fff;
}

/* ===== Header & Navigation ===== */
header {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    z-index: 1000;
    background: rgba(10, 22, 40, 0.85);
    backdrop-filter: blur(14px) saturate(180%);
    -webkit-backdrop-filter: blur(14px) saturate(180%);
    border-bottom: 1px solid var(--glass-border);
    transition: background var(--transition);
}

.light-mode header {
    background: rgba(248, 250, 252, 0.85);
    border-bottom: 1px solid rgba(0, 0, 0, 0.08);
}

nav {
    display: flex;
    align-items: center;
    justify-content: space-between;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0.6rem 1.5rem;
    gap: 1rem;
}

.logo a {
    display: flex;
    align-items: center;
}

nav ul {
    display: flex;
    gap: 0.4rem;
    flex-wrap: wrap;
}

nav ul li a {
    padding: 0.5rem 0.9rem;
    border-radius: 30px;
    font-size: 0.9rem;
    font-weight: 500;
    color: var(--text-light);
    transition: all var(--transition);
    white-space: nowrap;
}

.light-mode nav ul li a {
    color: var(--text-dark);
}

nav ul li a:hover,
nav ul li a:focus-visible {
    background: rgba(234, 179, 8, 0.15);
    color: var(--primary);
}

#darkModeToggle, #mobileMenuBtn {
    background: var(--glass-bg);
    border: 1px solid var(--glass-border);
    color: var(--text-light);
    padding: 0.5rem 0.9rem;
    border-radius: 30px;
    font-size: 1.2rem;
    cursor: pointer;
    transition: all var(--transition);
    backdrop-filter: blur(4px);
}

.light-mode #darkModeToggle,
.light-mode #mobileMenuBtn {
    color: var(--text-dark);
    background: rgba(0, 0, 0, 0.05);
    border-color: rgba(0, 0, 0, 0.1);
}

#darkModeToggle:hover, #mobileMenuBtn:hover {
    background: var(--primary);
    color: #0a1628;
    border-color: var(--primary);
}

#mobileMenuBtn {
    display: none;
}

/* ===== Hero Section ===== */
#hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 3rem;
    flex-wrap: wrap;
    padding-top: 6rem;
    position: relative;
    background: radial-gradient(ellipse at 20% 50%, rgba(234, 179, 8, 0.08) 0%, transparent 60%),
                radial-gradient(ellipse at 80% 50%, rgba(59, 130, 246, 0.05) 0%, transparent 60%);
    overflow: hidden;
}

#hero::before {
    content: '';
    position: absolute;
    top: -30%;
    left: -10%;
    width: 60%;
    height: 80%;
    background: radial-gradient(circle, rgba(234, 179, 8, 0.06) 0%, transparent 70%);
    pointer-events: none;
}

.hero-content {
    flex: 1 1 450px;
    max-width: 600px;
    animation: fadeSlideUp 0.9s ease forwards;
}

.hero-content h1 {
    margin-bottom: 1.2rem;
    background: linear-gradient(135deg, var(--primary) 0%, #fbbf24 50%, #fff 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.light-mode .hero-content h1 {
    background: linear-gradient(135deg, #b45309, var(--primary-dark), #0f172a);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-content h1 span {
    display: block;
    font-size: 0.7em;
    margin-top: 0.2rem;
    -webkit-text-fill-color: var(--text-muted);
    color: var(--text-muted);
}

.hero-content p {
    font-size: 1.1rem;
    margin-bottom: 2rem;
    max-width: 520px;
}

.hero-actions {
    display: flex;
    gap: 1rem;
    flex-wrap: wrap;
}

.hero-visual {
    flex: 0 0 auto;
    animation: float 6s ease-in-out infinite;
}

@keyframes fadeSlideUp {
    0% { opacity: 0; transform: translateY(40px); }
    100% { opacity: 1; transform: translateY(0); }
}

@keyframes float {
    0%, 100% { transform: translateY(0px); }
    50% { transform: translateY(-18px); }
}

/* ===== About Section ===== */
#about {
    position: relative;
}

.about-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
    gap: 1.8rem;
}

.about-grid article {
    background: var(--bg-dark-card);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    border: 1px solid var(--glass-border);
    border-radius: var(--radius);
    padding: 2rem 1.5rem;
    transition: all var(--transition);
    box-shadow: var(--shadow);
}

.light-mode .about-grid article {
    background: rgba(255, 255, 255, 0.7);
    border-color: rgba(0, 0, 0, 0.08);
}

.about-grid article:hover {
    transform: translateY(-8px);
    box-shadow: 0 16px 48px rgba(0, 0, 0, 0.4);
    border-color: rgba(234, 179, 8, 0.3);
}

/* ===== Products Section ===== */
#products {
    position: relative;
}

.products-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 1.8rem;
}

.products-grid article {
    background: var(--glass-bg);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border: 1px solid var(--glass-border);
    border-radius: var(--radius);
    padding: 2rem 1.5rem;
    transition: all var(--transition);
    position: relative;
    overflow: hidden;
}

.light-mode .products-grid article {
    background: rgba(255, 255, 255, 0.6);
    border-color: rgba(0, 0, 0, 0.08);
}

.products-grid article::before {
    content: '';
    position: absolute;
    top: -50%;
    left: -50%;
    width: 200%;
    height: 200%;
    background: radial-gradient(circle at 30% 30%, rgba(234, 179, 8, 0.04), transparent 60%);
    opacity: 0;
    transition: opacity var(--transition);
}

.products-grid article:hover::before {
    opacity: 1;
}

.products-grid article:hover {
    transform: translateY(-6px) scale(1.01);
    border-color: rgba(234, 179, 8, 0.25);
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.5);
}

.products-grid article a {
    display: inline-block;
    margin-top: 0.8rem;
    font-weight: 600;
    color: var(--primary);
    position: relative;
}

.products-grid article a::after {
    content: ' →';
    transition: margin var(--transition);
}

.products-grid article a:hover::after {
    margin-left: 6px;
}

/* ===== Features Section ===== */
#features {
    position: relative;
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
    gap: 1.8rem;
}

.features-grid article {
    background: linear-gradient(145deg, rgba(234, 179, 8, 0.06), transparent);
    border: 1px solid var(--glass-border);
    border-radius: var(--radius);
    padding: 2rem 1.5rem;
    text-align: center;
    transition: all var(--transition);
    backdrop-filter: blur(6px);
}

.light-mode .features-grid article {
    background: rgba(255, 255, 255, 0.5);
    border-color: rgba(0, 0, 0, 0.06);
}

.features-grid article:hover {
    background: linear-gradient(145deg, rgba(234, 179, 8, 0.12), rgba(234, 179, 8, 0.02));
    transform: scale(1.03);
    border-color: rgba(234, 179, 8, 0.3);
}

.features-grid article h3 {
    color: var(--primary);
}

/* ===== Resources Section ===== */
#resources {
    position: relative;
}

.resources-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
    gap: 1.8rem;
}

.resources-grid article {
    background: var(--bg-dark-card);
    backdrop-filter: blur(8px);
    border: 1px solid var(--glass-border);
    border-radius: var(--radius);
    padding: 1.8rem 1.5rem;
    transition: all var(--transition);
}

.light-mode .resources-grid article {
    background: rgba(255, 255, 255, 0.65);
    border-color: rgba(0, 0, 0, 0.06);
}

.resources-grid article:hover {
    transform: translateY(-5px);
    box-shadow: 0 12px 40px rgba(0, 0, 0, 0.35);
    border-color: rgba(234, 179, 8, 0.2);
}

.resources-grid article a {
    font-weight: 600;
}

/* ===== HowTo Section ===== */
#howto {
    position: relative;
}

#howto ol {
    counter-reset: step;
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 1.8rem;
}

#howto ol li {
    counter-increment: step;
    background: var(--glass-bg);
    backdrop-filter: blur(8px);
    border: 1px solid var(--glass-border);
    border-radius: var(--radius);
    padding: 2rem 1.5rem 1.5rem;
    position: relative;
    transition: all var(--transition);
}

.light-mode #howto ol li {
    background: rgba(255, 255, 255, 0.5);
    border-color: rgba(0, 0, 0, 0.06);
}

#howto ol li::before {
    content: counter(step);
    position: absolute;
    top: -12px;
    left: 20px;
    background: var(--primary);
    color: #0a1628;
    font-weight: 800;
    font-size: 1.1rem;
    width: 32px;
    height: 32px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 50%;
    box-shadow: 0 4px 12px rgba(234, 179, 8, 0.3);
}

#howto ol li:hover {
    transform: translateY(-4px);
    border-color: rgba(234, 179, 8, 0.2);
}

/* ===== FAQ Section ===== */
#faq {
    position: relative;
}

.faq-list {
    display: flex;
    flex-direction: column;
    gap: 0.8rem;
}

details {
    background: var(--bg-dark-card);
    backdrop-filter: blur(8px);
    border: 1px solid var(--glass-border);
    border-radius: var(--radius-sm);
    padding: 0.6rem 1.2rem;
    transition: all var(--transition);
    cursor: pointer;
}

.light-mode details {
    background: rgba(255, 255, 255, 0.55);
    border-color: rgba(0, 0, 0, 0.06);
}

details:hover {
    border-color: rgba(234, 179, 8, 0.2);
    box-shadow: 0 4px 16px rgba(0, 0, 0, 0.2);
}

details[open] {
    border-color: rgba(234, 179, 8, 0.3);
    padding-bottom: 1rem;
}

summary {
    font-weight: 600;
    padding: 0.6rem 0;
    list-style: none;
    display: flex;
    align-items: center;
    justify-content: space-between;
    cursor: pointer;
    color: var(--text-light);
}

.light-mode summary {
    color: var(--text-dark);
}

summary::-webkit-details-marker {
    display: none;
}

summary::after {
    content: '+';
    font-size: 1.4rem;
    font-weight: 300;
    color: var(--primary);
    transition: transform var(--transition);
}

details[open] summary::after {
    content: '−';
    transform: rotate(180deg);
}

details p {
    padding: 0.6rem 0 0.2rem;
    border-top: 1px solid var(--glass-border);
    margin-top: 0.4rem;
}

/* ===== Contact Section ===== */
#contact {
    position: relative;
}

.contact-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 2rem;
}

.contact-grid div {
    background: var(--glass-bg);
    backdrop-filter: blur(10px);
    border: 1px solid var(--glass-border);
    border-radius: var(--radius);
    padding: 2rem 1.5rem;
    transition: all var(--transition);
}

.light-mode .contact-grid div {
    background: rgba(255, 255, 255, 0.5);
    border-color: rgba(0, 0, 0, 0.06);
}

.contact-grid div:hover {
    transform: translateY(-4px);
    border-color: rgba(234, 179, 8, 0.2);
}

.contact-grid h3 {
    color: var(--primary);
}

/* ===== Footer ===== */
footer {
    background: rgba(0, 0, 0, 0.3);
    backdrop-filter: blur(10px);
    border-top: 1px solid var(--glass-border);
    padding: 2.5rem 1.5rem 1.5rem;
    text-align: center;
}

.light-mode footer {
    background: rgba(255, 255, 255, 0.4);
    border-top: 1px solid rgba(0, 0, 0, 0.06);
}

.footer-content {
    max-width: 900px;
    margin: 0 auto;
}

.footer-links {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 1rem 2rem;
    margin-bottom: 1.2rem;
}

.footer-links a {
    font-size: 0.9rem;
    color: var(--text-muted);
    transition: color var(--transition);
}

.footer-links a:hover {
    color: var(--primary);
}

footer p {
    font-size: 0.85rem;
    color: var(--text-muted);
    margin-bottom: 0.3rem;
}

/* ===== Back to Top ===== */
#backToTop {
    position: fixed;
    bottom: 2rem;
    right: 2rem;
    width: 48px;
    height: 48px;
    border-radius: 50%;
    background: var(--primary);
    color: #0a1628;
    border: none;
    font-size: 1.5rem;
    font-weight: bold;
    cursor: pointer;
    box-shadow: 0 4px 20px rgba(234, 179, 8, 0.3);
    transition: all var(--transition);
    opacity: 0;
    transform: scale(0.8);
    pointer-events: none;
    z-index: 999;
}

#backToTop.show {
    opacity: 1;
    transform: scale(1);
    pointer-events: auto;
}

#backToTop:hover {
    transform: scale(1.1) translateY(-4px);
    box-shadow: 0 8px 30px rgba(234, 179, 8, 0.5);
}

/* ===== Responsive ===== */
@media (max-width: 768px) {
    section {
        padding: 3rem 1rem;
    }

    nav ul {
        display: none;
        flex-direction: column;
        position: absolute;
        top: 100%;
        left: 0;
        width: 100%;
        background: rgba(10, 22, 40, 0.96);
        backdrop-filter: blur(20px);
        padding: 1rem 1.5rem 1.5rem;
        border-bottom: 1px solid var(--glass-border);
        gap: 0.2rem;
    }

    .light-mode nav ul {
        background: rgba(248, 250, 252, 0.96);
    }

    nav ul.open {
        display: flex;
    }

    #mobileMenuBtn {
        display: inline-block;
    }

    #hero {
        flex-direction: column;
        text-align: center;
        padding-top: 5rem;
        gap: 1.5rem;
    }

    .hero-actions {
        justify-content: center;
    }

    .hero-visual svg {
        width: 280px;
        height: auto;
    }

    .about-grid,
    .products-grid,
    .features-grid,
    .resources-grid,
    #howto ol {
        grid-template-columns: 1fr;
    }

    #howto ol {
        gap: 1.5rem;
    }

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

    #backToTop {
        bottom: 1.2rem;
        right: 1.2rem;
        width: 42px;
        height: 42px;
        font-size: 1.2rem;
    }
}

@media (max-width: 480px) {
    nav {
        padding: 0.4rem 0.8rem;
    }

    .logo svg {
        width: 140px;
        height: auto;
    }

    .hero-content h1 {
        font-size: 1.6rem;
    }

    .hero-visual svg {
        width: 220px;
    }

    .btn-primary, .btn-secondary {
        padding: 0.7rem 1.6rem;
        font-size: 0.9rem;
    }
}

/* ===== 滚动动画辅助类 ===== */
@media (prefers-reduced-motion: reduce) {
    *, *::before, *::after {
        animation-duration: 0.01ms !important;
        transition-duration: 0.01ms !important;
    }
}