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

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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, sans-serif;
    background: #0f0f1a;
    color: #e0e0e0;
    line-height: 1.7;
    transition: background 0.3s, color 0.3s;
    overflow-x: hidden;
}

a {
    color: #e94560;
    text-decoration: none;
    transition: color 0.2s;
}

a:hover {
    text-decoration: underline;
    color: #ff6b81;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* ===== 滚动动画 ===== */
@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.section,
.hero,
footer {
    animation: fadeInUp 0.8s ease-out;
}

/* ===== Header / 导航 ===== */
header {
    background: rgba(26, 26, 46, 0.85);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    padding: 15px 0;
    position: sticky;
    top: 0;
    z-index: 100;
    border-bottom: 2px solid #e94560;
    transition: background 0.3s;
}

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

.logo {
    font-size: 1.8rem;
    font-weight: 700;
    color: #e94560;
    text-shadow: 0 0 20px rgba(233, 69, 96, 0.3);
    letter-spacing: 1px;
}

.nav-links {
    display: flex;
    gap: 25px;
    flex-wrap: wrap;
}

.nav-links a {
    color: #ccc;
    font-size: 0.95rem;
    padding: 5px 0;
    border-bottom: 2px solid transparent;
    transition: color 0.2s, border-color 0.2s;
    position: relative;
}

.nav-links a::after {
    content: '';
    position: absolute;
    bottom: -2px;
    left: 0;
    width: 0;
    height: 2px;
    background: #e94560;
    transition: width 0.3s;
}

.nav-links a:hover {
    color: #fff;
    text-decoration: none;
}

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

/* ===== Hero 区域 (渐变Banner) ===== */
.hero {
    background: linear-gradient(135deg, #1a1a2e 0%, #16213e 40%, #0f3460 70%, #1a1a2e 100%);
    background-size: 200% 200%;
    animation: gradientShift 12s ease infinite;
    padding: 120px 0;
    text-align: center;
    position: relative;
    overflow: hidden;
}

@keyframes gradientShift {
    0% { background-position: 0% 50%; }
    50% { background-position: 100% 50%; }
    100% { background-position: 0% 50%; }
}

.hero::before {
    content: '';
    position: absolute;
    top: -50%;
    left: -50%;
    width: 200%;
    height: 200%;
    background: radial-gradient(circle at 30% 50%, rgba(233, 69, 96, 0.08) 0%, transparent 50%);
    animation: pulseGlow 6s ease-in-out infinite;
    pointer-events: none;
}

@keyframes pulseGlow {
    0%, 100% { transform: scale(1); opacity: 0.6; }
    50% { transform: scale(1.2); opacity: 1; }
}

.hero h1 {
    font-size: 3rem;
    margin-bottom: 20px;
    color: #fff;
    text-shadow: 0 4px 20px rgba(0, 0, 0, 0.5);
    position: relative;
    z-index: 1;
}

.hero p {
    font-size: 1.2rem;
    max-width: 700px;
    margin: 0 auto 30px;
    color: #bbb;
    position: relative;
    z-index: 1;
}

.hero .btn {
    background: linear-gradient(135deg, #e94560, #c73e54);
    color: #fff;
    padding: 14px 40px;
    border-radius: 30px;
    font-size: 1.1rem;
    display: inline-block;
    transition: transform 0.3s, box-shadow 0.3s, background 0.3s;
    box-shadow: 0 4px 15px rgba(233, 69, 96, 0.3);
    position: relative;
    z-index: 1;
}

.hero .btn:hover {
    transform: translateY(-4px) scale(1.02);
    box-shadow: 0 8px 30px rgba(233, 69, 96, 0.5);
    background: linear-gradient(135deg, #ff6b81, #e94560);
    text-decoration: none;
}

/* ===== 通用 Section ===== */
.section {
    padding: 80px 0;
    border-bottom: 1px solid #222;
}

.section h2 {
    font-size: 2rem;
    margin-bottom: 40px;
    color: #fff;
    text-align: center;
    position: relative;
}

.section h2::after {
    content: '';
    display: block;
    width: 60px;
    height: 3px;
    background: #e94560;
    margin: 12px auto 0;
    border-radius: 2px;
}

.section h3 {
    font-size: 1.4rem;
    margin-bottom: 15px;
    color: #e94560;
}

/* ===== Grid 卡片布局 (圆角卡片 + hover动画) ===== */
.grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 30px;
}

.card {
    background: rgba(30, 30, 50, 0.75);
    backdrop-filter: blur(8px);
    -webkit-backdrop-filter: blur(8px);
    padding: 30px;
    border-radius: 16px;
    transition: transform 0.3s, box-shadow 0.3s, background 0.3s;
    border: 1px solid rgba(255, 255, 255, 0.05);
}

.card:hover {
    transform: translateY(-8px) scale(1.01);
    box-shadow: 0 16px 40px rgba(0, 0, 0, 0.5);
    background: rgba(40, 40, 65, 0.85);
    border-color: rgba(233, 69, 96, 0.2);
}

.card p {
    color: #aaa;
    font-size: 0.95rem;
    line-height: 1.7;
}

/* ===== Workflow 步骤 ===== */
.workflow-steps {
    display: flex;
    flex-wrap: wrap;
    gap: 20px;
    justify-content: center;
}

.step {
    background: rgba(30, 30, 50, 0.7);
    backdrop-filter: blur(6px);
    -webkit-backdrop-filter: blur(6px);
    padding: 25px;
    border-radius: 16px;
    flex: 1 1 200px;
    text-align: center;
    border-left: 4px solid #e94560;
    transition: transform 0.3s, box-shadow 0.3s;
}

.step:hover {
    transform: translateY(-6px);
    box-shadow: 0 12px 30px rgba(0, 0, 0, 0.4);
}

.step .num {
    font-size: 2rem;
    color: #e94560;
    font-weight: 700;
    display: block;
    margin-bottom: 8px;
}

/* ===== FAQ ===== */
.faq-item {
    margin-bottom: 15px;
    border: 1px solid #333;
    border-radius: 12px;
    overflow: hidden;
    background: rgba(26, 26, 46, 0.5);
    backdrop-filter: blur(4px);
    -webkit-backdrop-filter: blur(4px);
}

.faq-question {
    background: rgba(30, 30, 50, 0.8);
    padding: 18px 25px;
    cursor: pointer;
    font-weight: 600;
    display: flex;
    justify-content: space-between;
    align-items: center;
    user-select: none;
    transition: background 0.3s;
}

.faq-question:hover {
    background: rgba(40, 40, 65, 0.9);
}

.faq-question::after {
    content: '+';
    font-size: 1.5rem;
    color: #e94560;
    transition: transform 0.3s;
}

.faq-question.active::after {
    content: '−';
    transform: rotate(180deg);
}

.faq-answer {
    padding: 0 25px;
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.4s ease, padding 0.4s ease;
    background: rgba(21, 21, 42, 0.9);
}

.faq-answer.open {
    padding: 18px 25px;
    max-height: 400px;
}

/* ===== HowTo ===== */
.howto {
    padding: 40px;
    background: rgba(30, 30, 50, 0.7);
    backdrop-filter: blur(6px);
    -webkit-backdrop-filter: blur(6px);
    border-radius: 16px;
    margin-top: 30px;
    border: 1px solid rgba(255, 255, 255, 0.05);
}

.howto ol {
    padding-left: 20px;
    color: #ccc;
}

.howto li {
    margin-bottom: 12px;
    transition: color 0.2s;
}

.howto li:hover {
    color: #fff;
}

/* ===== Articles ===== */
.articles-list {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 20px;
}

.article-item {
    background: rgba(30, 30, 50, 0.7);
    backdrop-filter: blur(4px);
    -webkit-backdrop-filter: blur(4px);
    padding: 20px;
    border-radius: 12px;
    transition: transform 0.3s, box-shadow 0.3s;
    border: 1px solid transparent;
}

.article-item:hover {
    transform: translateY(-4px);
    box-shadow: 0 8px 20px rgba(0, 0, 0, 0.4);
    border-color: rgba(233, 69, 96, 0.2);
}

.article-item h4 {
    margin-bottom: 8px;
    color: #fff;
}

.article-item p {
    font-size: 0.9rem;
    color: #999;
}

/* ===== Footer ===== */
footer {
    background: rgba(10, 10, 21, 0.9);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    padding: 50px 0 30px;
    text-align: center;
    color: #888;
    font-size: 0.9rem;
    border-top: 1px solid #222;
}

footer .footer-links {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 20px;
    margin-bottom: 30px;
}

footer .footer-links a {
    color: #aaa;
    transition: color 0.2s;
}

footer .footer-links a:hover {
    color: #e94560;
    text-decoration: none;
}

/* ===== Back to Top ===== */
.back-to-top {
    position: fixed;
    bottom: 30px;
    right: 30px;
    background: linear-gradient(135deg, #e94560, #c73e54);
    color: #fff;
    width: 50px;
    height: 50px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    cursor: pointer;
    opacity: 0.8;
    transition: opacity 0.3s, transform 0.3s, box-shadow 0.3s;
    z-index: 200;
    box-shadow: 0 4px 15px rgba(233, 69, 96, 0.3);
}

.back-to-top:hover {
    opacity: 1;
    transform: translateY(-3px);
    box-shadow: 0 8px 25px rgba(233, 69, 96, 0.5);
}

/* ===== 辅助类 ===== */
.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    border: 0;
}

/* ===== 响应式布局 (手机自适应) ===== */
@media (max-width: 768px) {
    .hero {
        padding: 80px 0;
    }

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

    .hero p {
        font-size: 1rem;
    }

    .nav-links {
        gap: 12px;
        margin-top: 10px;
        justify-content: center;
    }

    .nav-links a {
        font-size: 0.85rem;
    }

    .section {
        padding: 50px 0;
    }

    .section h2 {
        font-size: 1.6rem;
    }

    .section h3 {
        font-size: 1.2rem;
    }

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

    .workflow-steps {
        flex-direction: column;
    }

    .step {
        flex: 1 1 auto;
    }

    .howto {
        padding: 25px;
    }

    .back-to-top {
        bottom: 20px;
        right: 20px;
        width: 44px;
        height: 44px;
        font-size: 1.2rem;
    }

    .logo {
        font-size: 1.5rem;
    }
}

@media (max-width: 480px) {
    .hero h1 {
        font-size: 1.6rem;
    }

    .hero p {
        font-size: 0.9rem;
    }

    .hero .btn {
        padding: 12px 30px;
        font-size: 1rem;
    }

    .container {
        padding: 0 15px;
    }

    .card {
        padding: 20px;
    }

    .faq-question {
        padding: 14px 18px;
        font-size: 0.9rem;
    }

    .faq-answer.open {
        padding: 14px 18px;
    }
}