/* ===== CSS 变量 & 重置 ===== */
:root {
    --bg-body: #f5f7fe;
    --bg-card: #ffffff;
    --text-primary: #1e1e2f;
    --text-secondary: #4a4a6a;
    --text-muted: #7b7b9e;
    --accent-1: #6366f1;
    --accent-2: #8b5cf6;
    --accent-3: #06b6d4;
    --gradient-main: linear-gradient(135deg, #6366f1, #8b5cf6, #06b6d4);
    --shadow-sm: 0 4px 12px rgba(99, 102, 241, 0.08);
    --shadow-md: 0 8px 30px rgba(99, 102, 241, 0.15);
    --shadow-lg: 0 20px 60px rgba(99, 102, 241, 0.2);
    --radius-sm: 12px;
    --radius-md: 20px;
    --radius-lg: 28px;
    --transition: 0.25s cubic-bezier(0.4, 0, 0.2, 1);
    --font: 'Inter', system-ui, -apple-system, sans-serif;
}
* { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
    font-family: var(--font);
    background: var(--bg-body);
    color: var(--text-primary);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
}
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px;
}
.section {
    padding: 80px 0;
}
.section-header {
    text-align: center;
    margin-bottom: 48px;
}
.section-badge {
    display: inline-block;
    background: linear-gradient(135deg, rgba(99,102,241,0.12), rgba(139,92,246,0.12));
    color: var(--accent-1);
    font-weight: 600;
    font-size: 0.85rem;
    padding: 6px 18px;
    border-radius: 50px;
    letter-spacing: 0.3px;
    margin-bottom: 16px;
}
.section-header h2 {
    font-size: 2.4rem;
    font-weight: 700;
    margin-bottom: 12px;
    background: var(--gradient-main);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}
.section-header p {
    color: var(--text-secondary);
    font-size: 1.1rem;
    max-width: 600px;
    margin: 0 auto;
}

/* ===== 导航 ===== */
.navbar {
    position: fixed;
    width: 100%;
    top: 0;
    left: 0;
    z-index: 1000;
    background: rgba(255,255,255,0.75);
    backdrop-filter: blur(18px) saturate(180%);
    -webkit-backdrop-filter: blur(18px) saturate(180%);
    border-bottom: 1px solid rgba(99,102,241,0.08);
    transition: var(--transition);
}
.navbar.scrolled {
    background: rgba(255,255,255,0.92);
    box-shadow: 0 4px 20px rgba(0,0,0,0.04);
}
.nav-container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 68px;
}
.logo {
    display: flex;
    align-items: center;
    gap: 10px;
    text-decoration: none;
    color: var(--text-primary);
    font-weight: 700;
    font-size: 1.4rem;
}
.logo-icon i {
    font-size: 1.8rem;
    background: var(--gradient-main);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}
.logo-text { letter-spacing: -0.5px; }
.nav-links {
    display: flex;
    gap: 32px;
    align-items: center;
}
.nav-links a {
    text-decoration: none;
    color: var(--text-secondary);
    font-weight: 500;
    font-size: 0.95rem;
    transition: var(--transition);
    position: relative;
}
.nav-links a::after {
    content: '';
    position: absolute;
    bottom: -4px;
    left: 0;
    width: 0;
    height: 2.5px;
    background: var(--gradient-main);
    border-radius: 4px;
    transition: var(--transition);
}
.nav-links a:hover, .nav-links a.active { color: var(--accent-1); }
.nav-links a:hover::after, .nav-links a.active::after { width: 100%; }

/* 汉堡菜单 */
.hamburger {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 8px;
}
.bar {
    width: 28px;
    height: 3px;
    background: var(--text-primary);
    border-radius: 4px;
    transition: var(--transition);
}

/* ===== Hero ===== */
.hero {
    padding: 140px 0 80px;
    position: relative;
    overflow: hidden;
    background: linear-gradient(170deg, #f0f2ff 0%, #ffffff 100%);
}
.hero-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 48px;
    align-items: center;
}
.hero-badge {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    background: linear-gradient(135deg, rgba(99,102,241,0.15), rgba(6,182,212,0.1));
    color: var(--accent-1);
    padding: 8px 20px;
    border-radius: 50px;
    font-weight: 600;
    font-size: 0.9rem;
    margin-bottom: 20px;
}
.hero h1 {
    font-size: 3.2rem;
    font-weight: 800;
    line-height: 1.2;
    margin-bottom: 20px;
}
.gradient-text {
    background: var(--gradient-main);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}
.hero-desc {
    color: var(--text-secondary);
    font-size: 1.15rem;
    max-width: 520px;
    margin-bottom: 28px;
}
.hero-actions {
    display: flex;
    gap: 16px;
    flex-wrap: wrap;
    margin-bottom: 36px;
}
.btn {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    padding: 14px 32px;
    border-radius: 60px;
    font-weight: 600;
    font-size: 1rem;
    border: none;
    cursor: pointer;
    transition: var(--transition);
    text-decoration: none;
    background: transparent;
}
.btn-primary {
    background: var(--gradient-main);
    color: #fff;
    box-shadow: 0 8px 24px rgba(99,102,241,0.35);
}
.btn-primary:hover {
    transform: translateY(-2px) scale(1.02);
    box-shadow: 0 12px 32px rgba(99,102,241,0.45);
}
.btn-glow { animation: glow-pulse 2s infinite alternate; }
@keyframes glow-pulse {
    0% { box-shadow: 0 8px 24px rgba(99,102,241,0.3); }
    100% { box-shadow: 0 8px 40px rgba(99,102,241,0.55); }
}
.btn-outline {
    border: 2px solid var(--accent-1);
    color: var(--accent-1);
    background: transparent;
}
.btn-outline:hover {
    background: var(--accent-1);
    color: #fff;
    transform: translateY(-2px);
}
.hero-stats {
    display: flex;
    gap: 36px;
}
.stat-item {
    display: flex;
    flex-direction: column;
}
.stat-number {
    font-size: 1.6rem;
    font-weight: 800;
    background: var(--gradient-main);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}
.stat-label {
    font-size: 0.85rem;
    color: var(--text-muted);
    font-weight: 500;
}
.hero-visual {
    position: relative;
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 300px;
}
.floating-cards {
    position: relative;
    width: 100%;
    height: 320px;
}
.float-card {
    position: absolute;
    background: var(--bg-card);
    backdrop-filter: blur(8px);
    padding: 16px 24px;
    border-radius: 16px;
    box-shadow: var(--shadow-md);
    font-weight: 600;
    display: flex;
    align-items: center;
    gap: 12px;
    font-size: 1rem;
    animation: float 6s ease-in-out infinite;
    color: var(--text-primary);
    border: 1px solid rgba(99,102,241,0.1);
}
.float-card i { color: var(--accent-1); font-size: 1.3rem; }
.card-1 { top: 0; left: 10%; animation-delay: 0s; }
.card-2 { top: 30%; right: 5%; animation-delay: 1.2s; }
.card-3 { bottom: 20%; left: 15%; animation-delay: 2.4s; }
.card-4 { bottom: 0; right: 15%; animation-delay: 0.6s; }
@keyframes float {
    0%, 100% { transform: translateY(0px); }
    50% { transform: translateY(-16px); }
}
.hero-glow {
    position: absolute;
    width: 400px;
    height: 400px;
    background: radial-gradient(circle, rgba(99,102,241,0.2) 0%, transparent 70%);
    border-radius: 50%;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    z-index: 0;
    pointer-events: none;
}
.hero-wave {
    position: absolute;
    bottom: -2px;
    left: 0;
    width: 100%;
    line-height: 0;
}

/* ===== 生成器 ===== */
.generator-card {
    background: var(--bg-card);
    border-radius: var(--radius-md);
    padding: 48px;
    box-shadow: var(--shadow-md);
    max-width: 720px;
    margin: 0 auto;
    border: 1px solid rgba(99,102,241,0.08);
}
.brand-form {
    display: flex;
    flex-direction: column;
    gap: 24px;
}
.form-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 20px;
}
.form-group {
    display: flex;
    flex-direction: column;
    gap: 8px;
}
.form-group label {
    font-weight: 600;
    color: var(--text-primary);
    font-size: 0.95rem;
    display: flex;
    align-items: center;
    gap: 8px;
}
.form-group label i { color: var(--accent-1); width: 18px; }
.form-group input, .form-group select {
    padding: 14px 18px;
    border: 2px solid #e8ecf4;
    border-radius: var(--radius-sm);
    font-size: 1rem;
    font-family: var(--font);
    background: #fafbff;
    transition: var(--transition);
    outline: none;
    color: var(--text-primary);
}
.form-group input:focus, .form-group select:focus {
    border-color: var(--accent-1);
    box-shadow: 0 0 0 4px rgba(99,102,241,0.12);
    background: #fff;
}
.btn-generate {
    width: 100%;
    justify-content: center;
    padding: 18px;
    font-size: 1.1rem;
    margin-top: 8px;
}
.loading-area {
    text-align: center;
    padding: 40px 0 20px;
}
.loader-ring {
    width: 56px;
    height: 56px;
    border: 5px solid #e8ecf4;
    border-top: 5px solid var(--accent-1);
    border-radius: 50%;
    animation: spin 0.9s linear infinite;
    margin: 0 auto 16px;
}
@keyframes spin { to { transform: rotate(360deg); } }
.loading-area p { color: var(--text-secondary); font-weight: 500; }

/* ===== 品牌结果 ===== */
.brand-result {
    background: var(--bg-body);
}
.result-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
    gap: 24px;
    margin-top: 20px;
}
.result-card {
    background: var(--bg-card);
    border-radius: var(--radius-sm);
    padding: 24px;
    box-shadow: var(--shadow-sm);
    border: 1px solid rgba(99,102,241,0.06);
    transition: var(--transition);
}
.result-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-md); }
.result-card .card-icon {
    font-size: 2rem;
    color: var(--accent-1);
    margin-bottom: 12px;
}
.result-card h4 {
    font-size: 1.1rem;
    margin-bottom: 8px;
    color: var(--text-primary);
}
.result-card p {
    color: var(--text-secondary);
    font-size: 0.95rem;
    line-height: 1.5;
}
.result-card .color-swatch {
    display: inline-block;
    width: 28px;
    height: 28px;
    border-radius: 50%;
    margin: 4px 6px 4px 0;
    border: 2px solid rgba(0,0,0,0.05);
    vertical-align: middle;
}
.result-actions {
    display: flex;
    justify-content: center;
    gap: 20px;
    margin-top: 36px;
    flex-wrap: wrap;
}

/* ===== 案例展示 ===== */
.showcase-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 28px;
}
.showcase-card {
    background: var(--bg-card);
    border-radius: var(--radius-sm);
    padding: 28px;
    box-shadow: var(--shadow-sm);
    transition: var(--transition);
    border: 1px solid rgba(99,102,241,0.06);
    position: relative;
    overflow: hidden;
}
.showcase-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 4px;
    background: var(--gradient-main);
    opacity: 0.6;
}
.showcase-card:hover { transform: translateY(-6px); box-shadow: var(--shadow-lg); }
.showcase-card .brand-icon {
    font-size: 2.4rem;
    margin-bottom: 12px;
}
.showcase-card h3 { font-size: 1.35rem; margin-bottom: 4px; }
.showcase-card .industry-tag {
    font-size: 0.8rem;
    color: var(--accent-1);
    background: rgba(99,102,241,0.1);
    display: inline-block;
    padding: 4px 14px;
    border-radius: 50px;
    font-weight: 600;
    margin: 6px 0 12px;
}
.showcase-card p { color: var(--text-secondary); font-size: 0.95rem; }
.showcase-card .mini-palette {
    display: flex;
    gap: 8px;
    margin-top: 16px;
}
.mini-palette span {
    width: 28px;
    height: 28px;
    border-radius: 50%;
    border: 2px solid rgba(0,0,0,0.04);
}

/* ===== 特色 ===== */
.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
    gap: 28px;
}
.feature-card {
    background: var(--bg-card);
    padding: 32px 24px;
    border-radius: var(--radius-sm);
    text-align: center;
    box-shadow: var(--shadow-sm);
    transition: var(--transition);
    border: 1px solid rgba(99,102,241,0.04);
}
.feature-card:hover { transform: translateY(-6px); box-shadow: var(--shadow-md); }
.feature-icon {
    width: 64px;
    height: 64px;
    background: linear-gradient(135deg, rgba(99,102,241,0.12), rgba(6,182,212,0.08));
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 16px;
    font-size: 1.8rem;
    color: var(--accent-1);
}
.feature-card h3 { font-size: 1.2rem; margin-bottom: 8px; }
.feature-card p { color: var(--text-secondary); font-size: 0.95rem; }

/* ===== FAQ ===== */
.faq-list {
    max-width: 720px;
    margin: 0 auto;
}
.faq-item {
    background: var(--bg-card);
    border-radius: var(--radius-sm);
    margin-bottom: 14px;
    box-shadow: var(--shadow-sm);
    overflow: hidden;
    border: 1px solid rgba(99,102,241,0.06);
}
.faq-question {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 20px 24px;
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition);
    font-size: 1.05rem;
}
.faq-question i { transition: var(--transition); color: var(--accent-1); }
.faq-item.active .faq-question i { transform: rotate(180deg); }
.faq-answer {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.35s ease, padding 0.3s;
    padding: 0 24px;
    color: var(--text-secondary);
    line-height: 1.7;
}
.faq-item.active .faq-answer {
    max-height: 240px;
    padding: 0 24px 20px;
}

/* ===== 页脚 ===== */
.footer {
    background: #1e1e2f;
    color: #c7c7e0;
    padding: 40px 0;
    margin-top: 40px;
}
.footer-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 20px;
}
.footer-brand { display: flex; align-items: center; gap: 12px; }
.footer-brand .logo-icon i { color: #a5b4fc; font-size: 1.6rem; }
.footer-brand .logo-text { color: #fff; font-weight: 700; }
.footer-brand p { font-size: 0.85rem; margin-left: 8px; color: #9ca3d0; }
.footer-links span { font-size: 0.9rem; }

/* ===== 响应式 ===== */
@media (max-width: 768px) {
    .nav-links {
        position: fixed;
        top: 68px;
        left: 0;
        width: 100%;
        background: rgba(255,255,255,0.98);
        backdrop-filter: blur(18px);
        flex-direction: column;
        padding: 24px;
        gap: 20px;
        transform: translateX(100%);
        transition: var(--transition);
        box-shadow: 0 12px 40px rgba(0,0,0,0.08);
        border-top: 1px solid rgba(99,102,241,0.1);
    }
    .nav-links.open { transform: translateX(0); }
    .hamburger { display: flex; }
    .hero-grid { grid-template-columns: 1fr; text-align: center; }
    .hero h1 { font-size: 2.2rem; }
    .hero-desc { margin: 0 auto 28px; }
    .hero-actions { justify-content: center; }
    .hero-stats { justify-content: center; }
    .hero-visual { min-height: 220px; }
    .floating-cards { height: 240px; }
    .float-card { font-size: 0.85rem; padding: 12px 18px; }
    .form-row { grid-template-columns: 1fr; }
    .generator-card { padding: 28px; }
    .section { padding: 60px 0; }
    .section-header h2 { font-size: 1.8rem; }
    .footer-content { flex-direction: column; text-align: center; }
}
@media (max-width: 480px) {
    .hero h1 { font-size: 1.8rem; }
    .hero-stats { flex-wrap: wrap; gap: 20px; }
    .btn { padding: 12px 24px; font-size: 0.9rem; }
    .container { padding: 0 16px; }
}