/* ========================================
   软著通 - AI软著材料生成平台样式表
   ======================================== */

/* CSS变量定义 */
:root {
    /* 渐变色 */
    --primary-gradient: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    --secondary-gradient: linear-gradient(135deg, #f093fb 0%, #f5576c 100%);
    --accent-gradient: linear-gradient(135deg, #4f8cff 0%, #a855f7 100%);
    --glow-gradient: radial-gradient(circle, rgba(102, 126, 234, 0.3) 0%, transparent 70%);

    /* 主色调 */
    --accent-blue: #4f8cff;
    --accent-purple: #a855f7;
    --accent-cyan: #22d3ee;
    --accent-pink: #ec4899;

    /* 背景色 */
    --bg-primary: #f8fafc;
    --bg-secondary: #ffffff;
    --bg-card: #ffffff;
    --bg-dark: #0f172a;

    /* 文字色 */
    --text-primary: #1e293b;
    --text-secondary: #64748b;
    --text-muted: #94a3b8;
    --text-white: #ffffff;

    /* 边框 */
    --border-color: #e2e8f0;
    --border-light: #f1f5f9;

    /* 阴影 */
    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
    --shadow-soft: 0 4px 20px rgba(102, 126, 234, 0.1);
    --shadow-glow: 0 0 40px rgba(102, 126, 234, 0.15);
    --shadow-card-hover: 0 20px 40px rgba(102, 126, 234, 0.15);

    /* 圆角 */
    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 16px;
    --radius-xl: 24px;
    --radius-full: 9999px;

    /* 过渡 */
    --transition-fast: 150ms ease;
    --transition-normal: 200ms ease;
    --transition-slow: 300ms ease;

    /* 字体 */
    --font-heading: 'Plus Jakarta Sans', 'Noto Sans SC', sans-serif;
    --font-body: 'Inter', 'Noto Sans SC', sans-serif;
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-body);
    font-size: 16px;
    line-height: 1.6;
    color: var(--text-primary);
    background: var(--bg-primary);
    overflow-x: hidden;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

/* Container */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px;
}

/* Section */
.section {
    padding: 100px 0;
}

.section:nth-child(even) {
    background: var(--bg-secondary);
}

/* ========================================
   导航栏样式
   ======================================== */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    background: rgba(255, 255, 255, 0.8);
    backdrop-filter: blur(12px);
    border-bottom: 1px solid rgba(226, 232, 240, 0.5);
    transition: var(--transition-normal);
}

.navbar.scrolled {
    background: rgba(255, 255, 255, 0.95);
    box-shadow: var(--shadow-md);
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px;
    height: 72px;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.logo {
    display: flex;
    align-items: center;
    gap: 10px;
    text-decoration: none;
    color: var(--text-primary);
}

.logo-icon {
    width: 40px;
    height: 40px;
    background: var(--primary-gradient);
    border-radius: var(--radius-md);
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
}

.logo-icon svg {
    width: 22px;
    height: 22px;
}

.logo-text {
    font-family: var(--font-heading);
    font-size: 1.5rem;
    font-weight: 700;
    background: var(--primary-gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.nav-links {
    display: flex;
    align-items: center;
    gap: 32px;
    list-style: none;
}

.nav-link {
    text-decoration: none;
    color: var(--text-secondary);
    font-weight: 500;
    font-size: 0.95rem;
    position: relative;
    padding: 8px 0;
    transition: var(--transition-normal);
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--primary-gradient);
    transition: var(--transition-normal);
}

.nav-link:hover,
.nav-link.active {
    color: var(--accent-blue);
}

.nav-link:hover::after,
.nav-link.active::after {
    width: 100%;
}

.nav-actions {
    display: flex;
    align-items: center;
    gap: 16px;
}

.nav-user {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 8px 16px;
    background: var(--bg-secondary);
    border-radius: 20px;
    text-decoration: none;
    color: var(--text-primary);
    font-weight: 500;
    transition: var(--transition-normal);
}

.nav-user:hover {
    background: var(--bg-primary);
    box-shadow: var(--shadow-sm);
}

.nav-user-avatar {
    width: 28px;
    height: 28px;
    border-radius: 50%;
    background: var(--primary-gradient);
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-size: 0.8rem;
    font-weight: 600;
}

.mobile-menu-btn {
    display: none;
    width: 40px;
    height: 40px;
    border: none;
    background: transparent;
    cursor: pointer;
    color: var(--text-primary);
}

.mobile-menu-btn svg {
    width: 24px;
    height: 24px;
}

/* 移动端菜单 */
.mobile-menu {
    display: none;
    position: fixed;
    top: 72px;
    left: 0;
    right: 0;
    background: white;
    border-bottom: 1px solid var(--border-color);
    padding: 24px;
    box-shadow: var(--shadow-lg);
    z-index: 999;
}

.mobile-menu.active {
    display: block;
}

.mobile-nav-links {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: 16px;
}

.mobile-nav-links a {
    display: block;
    padding: 12px 0;
    color: var(--text-primary);
    text-decoration: none;
    font-weight: 500;
}

.mobile-nav-links .btn-block {
    margin-top: 16px;
    text-align: center;
}

/* ========================================
   按钮样式
   ======================================== */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    padding: 12px 24px;
    font-family: var(--font-body);
    font-size: 0.95rem;
    font-weight: 600;
    text-decoration: none;
    border: none;
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: var(--transition-normal);
}

.btn svg {
    width: 18px;
    height: 18px;
}

.btn-primary {
    background: var(--primary-gradient);
    color: white;
    box-shadow: 0 4px 14px rgba(102, 126, 234, 0.4);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(102, 126, 234, 0.5);
}

.btn-primary:active {
    transform: translateY(0);
}

.btn-secondary {
    background: var(--bg-secondary);
    color: var(--text-primary);
    border: 1px solid var(--border-color);
}

.btn-secondary:hover {
    background: var(--bg-primary);
    border-color: var(--accent-blue);
    color: var(--accent-blue);
}

.btn-white {
    background: white;
    color: var(--accent-purple);
    box-shadow: 0 4px 14px rgba(0, 0, 0, 0.1);
}

.btn-white:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(0, 0, 0, 0.15);
}

.btn-lg {
    padding: 16px 32px;
    font-size: 1rem;
}

.btn-block {
    width: 100%;
}

/* ========================================
   英雄区样式
   ======================================== */
.hero {
    position: relative;
    min-height: 100vh;
    display: flex;
    align-items: center;
    padding: 120px 0 80px;
    overflow: hidden;
}

.hero-bg {
    position: absolute;
    inset: 0;
    overflow: hidden;
}

.gradient-orb {
    position: absolute;
    border-radius: 50%;
    filter: blur(80px);
    opacity: 0.6;
    animation: float 20s ease-in-out infinite;
}

.orb-1 {
    width: 600px;
    height: 600px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    top: -200px;
    right: -100px;
    animation-delay: 0s;
}

.orb-2 {
    width: 400px;
    height: 400px;
    background: linear-gradient(135deg, #4f8cff 0%, #a855f7 100%);
    bottom: -100px;
    left: -100px;
    animation-delay: -5s;
}

.orb-3 {
    width: 300px;
    height: 300px;
    background: linear-gradient(135deg, #22d3ee 0%, #ec4899 100%);
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    animation-delay: -10s;
    opacity: 0.3;
}

@keyframes float {
    0%, 100% {
        transform: translate(0, 0) scale(1);
    }
    25% {
        transform: translate(30px, -30px) scale(1.05);
    }
    50% {
        transform: translate(-20px, 20px) scale(0.95);
    }
    75% {
        transform: translate(20px, 10px) scale(1.02);
    }
}

.hero-content {
    position: relative;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px;
    text-align: center;
}

.hero-badge {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 8px 16px;
    background: rgba(102, 126, 234, 0.1);
    border: 1px solid rgba(102, 126, 234, 0.2);
    border-radius: var(--radius-full);
    color: var(--accent-purple);
    font-size: 0.875rem;
    font-weight: 500;
    margin-bottom: 24px;
    animation: fadeInUp 0.6s ease-out;
}

.hero-badge svg {
    width: 16px;
    height: 16px;
}

.hero-title {
    font-family: var(--font-heading);
    font-size: clamp(2.5rem, 5vw, 4rem);
    font-weight: 800;
    line-height: 1.2;
    margin-bottom: 24px;
    color: var(--text-primary);
    animation: fadeInUp 0.6s ease-out 0.1s both;
}

.gradient-text {
    background: var(--primary-gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-subtitle {
    font-size: 1.25rem;
    color: var(--text-secondary);
    max-width: 600px;
    margin: 0 auto 40px;
    line-height: 1.8;
    animation: fadeInUp 0.6s ease-out 0.2s both;
}

.hero-actions {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 16px;
    margin-bottom: 32px;
    animation: fadeInUp 0.6s ease-out 0.3s both;
}

.hero-pricing {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 16px;
    margin-bottom: 60px;
    animation: fadeInUp 0.6s ease-out 0.35s both;
}

.pricing-badge {
    padding: 6px 14px;
    background: linear-gradient(135deg, #ff6b6b 0%, #ee5a24 100%);
    color: white;
    font-size: 0.8rem;
    font-weight: 600;
    border-radius: 20px;
    animation: pulse 2s ease-in-out infinite;
}

@keyframes pulse {
    0%, 100% { transform: scale(1); }
    50% { transform: scale(1.05); }
}

.pricing-info {
    display: flex;
    align-items: baseline;
    gap: 12px;
}

.pricing-current {
    display: flex;
    align-items: baseline;
}

.pricing-currency {
    font-size: 1.5rem;
    font-weight: 700;
    color: #ee5a24;
}

.pricing-amount {
    font-family: var(--font-heading);
    font-size: 3rem;
    font-weight: 800;
    color: #ee5a24;
    line-height: 1;
}

.pricing-unit {
    font-size: 0.9rem;
    color: var(--text-muted);
    margin-left: 4px;
}

.pricing-original {
    font-size: 0.9rem;
    color: var(--text-muted);
}

.original-price {
    text-decoration: line-through;
    color: var(--text-muted);
}

.hero-stats {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 40px;
    animation: fadeInUp 0.6s ease-out 0.4s both;
}

.stat-item {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 4px;
}

.stat-number {
    font-family: var(--font-heading);
    font-size: 2rem;
    font-weight: 700;
    background: var(--primary-gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.stat-label {
    font-size: 0.875rem;
    color: var(--text-muted);
}

.stat-divider {
    width: 1px;
    height: 40px;
    background: var(--border-color);
}

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* ========================================
   Section Header
   ======================================== */
.section-header {
    text-align: center;
    margin-bottom: 60px;
}

.section-tag {
    display: inline-block;
    padding: 6px 16px;
    background: rgba(102, 126, 234, 0.1);
    color: var(--accent-purple);
    font-size: 0.875rem;
    font-weight: 600;
    border-radius: var(--radius-full);
    margin-bottom: 16px;
}

.section-title {
    font-family: var(--font-heading);
    font-size: clamp(1.75rem, 3vw, 2.5rem);
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 16px;
}

.section-desc {
    font-size: 1.1rem;
    color: var(--text-secondary);
    max-width: 600px;
    margin: 0 auto;
}

/* ========================================
   功能卡片区
   ======================================== */
.features-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 32px;
}

.feature-card {
    position: relative;
    background: var(--bg-card);
    padding: 40px 32px;
    border-radius: var(--radius-xl);
    border: 1px solid var(--border-light);
    transition: var(--transition-slow);
    overflow: hidden;
}

.feature-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: var(--primary-gradient);
    transform: scaleX(0);
    transform-origin: left;
    transition: var(--transition-slow);
}

.feature-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-card-hover);
    border-color: transparent;
}

.feature-card:hover::before {
    transform: scaleX(1);
}

.feature-icon {
    width: 64px;
    height: 64px;
    background: rgba(102, 126, 234, 0.1);
    border-radius: var(--radius-lg);
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 24px;
    color: var(--accent-purple);
    transition: var(--transition-normal);
}

.feature-card:hover .feature-icon {
    background: var(--primary-gradient);
    color: white;
}

.feature-icon svg {
    width: 28px;
    height: 28px;
}

.feature-title {
    font-family: var(--font-heading);
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 12px;
}

.feature-desc {
    font-size: 0.95rem;
    color: var(--text-secondary);
    line-height: 1.7;
}

.feature-step {
    position: absolute;
    top: 24px;
    right: 24px;
    font-family: var(--font-heading);
    font-size: 3rem;
    font-weight: 800;
    color: rgba(102, 126, 234, 0.05);
}

/* ========================================
   优势区
   ======================================== */
.advantages {
    background: linear-gradient(180deg, var(--bg-secondary) 0%, var(--bg-primary) 100%);
}

.advantages-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
}

.advantage-item {
    display: flex;
    align-items: flex-start;
    gap: 20px;
    padding: 28px;
    background: var(--bg-card);
    border-radius: var(--radius-lg);
    border: 1px solid var(--border-light);
    transition: var(--transition-normal);
}

.advantage-item:hover {
    transform: translateX(8px);
    border-color: var(--accent-blue);
    box-shadow: var(--shadow-soft);
}

.advantage-icon {
    flex-shrink: 0;
    width: 52px;
    height: 52px;
    background: var(--primary-gradient);
    border-radius: var(--radius-md);
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
}

.advantage-icon svg {
    width: 24px;
    height: 24px;
}

.advantage-content {
    flex: 1;
}

.advantage-title {
    font-family: var(--font-heading);
    font-size: 1.1rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 8px;
}

.advantage-desc {
    font-size: 0.9rem;
    color: var(--text-secondary);
    line-height: 1.6;
}

/* ========================================
   生成表单区
   ======================================== */
.generate-section {
    background: var(--bg-primary);
    position: relative;
}

.generate-section::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 50%;
    background: linear-gradient(180deg, rgba(102, 126, 234, 0.03) 0%, transparent 100%);
    pointer-events: none;
}

.generate-form {
    max-width: 800px;
    margin: 0 auto;
    padding: 48px;
    background: var(--bg-card);
    border-radius: var(--radius-xl);
    border: 1px solid var(--border-light);
    box-shadow: var(--shadow-soft);
}

.form-group {
    margin-bottom: 28px;
}

.form-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 24px;
}

.form-label {
    display: flex;
    align-items: center;
    gap: 8px;
    font-size: 0.95rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 10px;
}

.form-label svg {
    width: 18px;
    height: 18px;
    color: var(--accent-purple);
}

.form-input,
.form-select,
.form-textarea {
    width: 100%;
    padding: 14px 18px;
    font-family: var(--font-body);
    font-size: 1rem;
    color: var(--text-primary);
    background: var(--bg-primary);
    border: 2px solid var(--border-color);
    border-radius: var(--radius-md);
    transition: var(--transition-normal);
}

.form-input:focus,
.form-select:focus,
.form-textarea:focus {
    outline: none;
    border-color: var(--accent-blue);
    box-shadow: 0 0 0 4px rgba(79, 140, 255, 0.1);
}

.form-input::placeholder,
.form-textarea::placeholder {
    color: var(--text-muted);
}

.form-select {
    cursor: pointer;
    appearance: none;
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='24' height='24' viewBox='0 0 24 24' fill='none' stroke='%2394a3b8' stroke-width='2' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpolyline points='6 9 12 15 18 9'%3E%3C/polyline%3E%3C/svg%3E");
    background-repeat: no-repeat;
    background-position: right 14px center;
    background-size: 18px;
    padding-right: 44px;
}

.form-textarea {
    min-height: 140px;
    resize: vertical;
    line-height: 1.7;
}

.form-hint {
    display: flex;
    align-items: center;
    gap: 6px;
    margin-top: 10px;
    font-size: 0.85rem;
    color: var(--text-muted);
}

.form-hint svg {
    width: 14px;
    height: 14px;
}

/* 单选按钮组 */
.radio-group {
    display: flex;
    flex-wrap: wrap;
    gap: 12px;
}

.radio-item {
    position: relative;
    cursor: pointer;
}

.radio-item input {
    position: absolute;
    opacity: 0;
    width: 0;
    height: 0;
}

.radio-label {
    display: inline-flex;
    align-items: center;
    padding: 10px 18px;
    background: var(--bg-primary);
    border: 2px solid var(--border-color);
    border-radius: var(--radius-md);
    font-size: 0.9rem;
    font-weight: 500;
    color: var(--text-secondary);
    transition: var(--transition-normal);
}

.radio-item:hover .radio-label {
    border-color: var(--accent-blue);
    color: var(--accent-blue);
}

.radio-item input:checked + .radio-label {
    background: rgba(102, 126, 234, 0.1);
    border-color: var(--accent-purple);
    color: var(--accent-purple);
}

.btn-generate {
    width: 100%;
    margin-top: 12px;
    padding: 18px 32px;
    font-size: 1.1rem;
}

/* ========================================
   案例展示区
   ======================================== */
.cases {
    background: var(--bg-secondary);
    overflow: hidden;
}

.cases-carousel {
    position: relative;
}

.cases-track {
    display: flex;
    gap: 24px;
    overflow-x: auto;
    scroll-snap-type: x mandatory;
    scroll-behavior: smooth;
    padding: 20px 0;
    margin: 0 -24px;
    padding-left: 24px;
    padding-right: 24px;
    -ms-overflow-style: none;
    scrollbar-width: none;
}

.cases-track::-webkit-scrollbar {
    display: none;
}

.case-card {
    flex-shrink: 0;
    width: 320px;
    background: var(--bg-card);
    border-radius: var(--radius-lg);
    border: 1px solid var(--border-light);
    overflow: hidden;
    scroll-snap-align: start;
    transition: var(--transition-slow);
}

.case-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-card-hover);
}

.case-screenshot {
    height: 180px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    display: flex;
    align-items: center;
    justify-content: center;
}

.screenshot-placeholder {
    width: 80px;
    height: 80px;
    background: rgba(255, 255, 255, 0.2);
    border-radius: var(--radius-lg);
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
}

.screenshot-placeholder svg {
    width: 40px;
    height: 40px;
}

.case-content {
    padding: 24px;
}

.case-badge {
    display: inline-flex;
    padding: 4px 12px;
    font-size: 0.75rem;
    font-weight: 600;
    border-radius: var(--radius-full);
    margin-bottom: 12px;
}

.case-badge.success {
    background: rgba(34, 197, 94, 0.1);
    color: #16a34a;
}

.case-title {
    font-family: var(--font-heading);
    font-size: 1.15rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 8px;
}

.case-info {
    font-size: 0.85rem;
    color: var(--text-muted);
    margin-bottom: 12px;
}

.case-meta {
    display: flex;
    align-items: center;
    gap: 8px;
    font-size: 0.85rem;
    color: var(--text-secondary);
}

.case-meta svg {
    width: 14px;
    height: 14px;
}

/* 轮播控制 */
.carousel-controls {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 16px;
    margin-top: 32px;
}

.carousel-btn {
    width: 44px;
    height: 44px;
    border: 2px solid var(--border-color);
    background: var(--bg-card);
    border-radius: var(--radius-full);
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: var(--transition-normal);
    color: var(--text-secondary);
}

.carousel-btn:hover {
    border-color: var(--accent-purple);
    color: var(--accent-purple);
    background: rgba(168, 85, 247, 0.05);
}

.carousel-btn svg {
    width: 20px;
    height: 20px;
}

.carousel-dots {
    display: flex;
    gap: 8px;
}

.carousel-dot {
    width: 8px;
    height: 8px;
    background: var(--border-color);
    border-radius: var(--radius-full);
    cursor: pointer;
    transition: var(--transition-normal);
}

.carousel-dot.active {
    width: 24px;
    background: var(--accent-purple);
}

/* ========================================
   FAQ 问答区
   ======================================== */
.faq {
    background: var(--bg-primary);
}

.faq-list {
    max-width: 800px;
    margin: 0 auto;
}

.faq-item {
    background: var(--bg-card);
    border-radius: var(--radius-lg);
    border: 1px solid var(--border-light);
    margin-bottom: 16px;
    overflow: hidden;
    transition: var(--transition-normal);
}

.faq-item:hover {
    border-color: var(--accent-blue);
}

.faq-item.active {
    border-color: var(--accent-purple);
    box-shadow: var(--shadow-soft);
}

.faq-question {
    width: 100%;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 16px;
    padding: 20px 24px;
    background: none;
    border: none;
    cursor: pointer;
    font-family: var(--font-body);
    font-size: 1rem;
    font-weight: 600;
    color: var(--text-primary);
    text-align: left;
    transition: var(--transition-normal);
}

.faq-question:hover {
    color: var(--accent-purple);
}

.faq-question svg {
    flex-shrink: 0;
    width: 20px;
    height: 20px;
    color: var(--text-muted);
    transition: var(--transition-normal);
}

.faq-item.active .faq-question svg {
    transform: rotate(180deg);
    color: var(--accent-purple);
}

.faq-answer {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.3s ease;
}

.faq-item.active .faq-answer {
    max-height: 300px;
}

.faq-answer p {
    padding: 0 24px 20px;
    font-size: 0.95rem;
    color: var(--text-secondary);
    line-height: 1.8;
}

/* ========================================
   帮助中心
   ======================================== */
.help {
    background: var(--bg-secondary);
}

.help-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 24px;
}

.help-card {
    background: var(--bg-card);
    padding: 32px;
    border-radius: var(--radius-lg);
    border: 1px solid var(--border-light);
    text-align: center;
    transition: var(--transition-slow);
}

.help-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-card-hover);
    border-color: transparent;
}

.help-icon {
    width: 72px;
    height: 72px;
    margin: 0 auto 20px;
    background: rgba(102, 126, 234, 0.1);
    border-radius: var(--radius-lg);
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--accent-purple);
    transition: var(--transition-normal);
}

.help-card:hover .help-icon {
    background: var(--primary-gradient);
    color: white;
}

.help-icon svg {
    width: 32px;
    height: 32px;
}

.help-title {
    font-family: var(--font-heading);
    font-size: 1.1rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 10px;
}

.help-desc {
    font-size: 0.9rem;
    color: var(--text-secondary);
    margin-bottom: 20px;
    line-height: 1.6;
}

.help-link {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    color: var(--accent-purple);
    font-size: 0.9rem;
    font-weight: 600;
    text-decoration: none;
    transition: var(--transition-normal);
}

.help-link:hover {
    gap: 10px;
}

.help-link svg {
    width: 16px;
    height: 16px;
}

/* ========================================
   CTA 区域
   ======================================== */
.cta {
    padding: 80px 0;
    background: var(--bg-primary);
}

.cta-box {
    position: relative;
    background: var(--primary-gradient);
    border-radius: var(--radius-xl);
    padding: 80px 40px;
    overflow: hidden;
    text-align: center;
}

.cta-bg {
    position: absolute;
    inset: 0;
    overflow: hidden;
}

.cta-orb {
    position: absolute;
    width: 500px;
    height: 500px;
    background: rgba(255, 255, 255, 0.1);
    border-radius: 50%;
    filter: blur(80px);
    top: -200px;
    right: -100px;
    animation: float 15s ease-in-out infinite;
}

.cta-content {
    position: relative;
    z-index: 1;
}

.cta-title {
    font-family: var(--font-heading);
    font-size: clamp(1.75rem, 3vw, 2.5rem);
    font-weight: 700;
    color: white;
    margin-bottom: 16px;
}

.cta-desc {
    font-size: 1.1rem;
    color: rgba(255, 255, 255, 0.9);
    margin-bottom: 32px;
}

/* ========================================
   页脚
   ======================================== */
.footer {
    background: var(--bg-dark);
    padding: 80px 0 40px;
    color: rgba(255, 255, 255, 0.7);
}

.footer-main {
    display: grid;
    grid-template-columns: 1fr 2fr;
    gap: 60px;
    margin-bottom: 60px;
}

.footer-brand .logo {
    margin-bottom: 16px;
}

.footer-brand .logo-icon {
    background: rgba(255, 255, 255, 0.1);
}

.footer-brand .logo-text {
    color: white;
    -webkit-text-fill-color: white;
}

.footer-tagline {
    font-size: 0.95rem;
    max-width: 280px;
    line-height: 1.7;
}

.footer-links {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 40px;
}

.footer-column h4 {
    font-family: var(--font-heading);
    font-size: 1rem;
    font-weight: 600;
    color: white;
    margin-bottom: 20px;
}

.footer-column ul {
    list-style: none;
}

.footer-column li {
    margin-bottom: 12px;
}

.footer-column a {
    color: rgba(255, 255, 255, 0.6);
    text-decoration: none;
    font-size: 0.9rem;
    transition: var(--transition-normal);
}

.footer-column a:hover {
    color: var(--accent-purple);
}

.footer-bottom {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding-top: 40px;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
}

.footer-bottom p {
    font-size: 0.85rem;
}

.footer-legal {
    display: flex;
    gap: 24px;
}

.footer-legal a {
    color: rgba(255, 255, 255, 0.5);
    text-decoration: none;
    font-size: 0.85rem;
    transition: var(--transition-normal);
}

.footer-legal a:hover {
    color: var(--accent-purple);
}

/* ========================================
   Toast 提示
   ======================================== */
.toast {
    position: fixed;
    bottom: 30px;
    left: 50%;
    transform: translateX(-50%) translateY(100px);
    background: var(--bg-card);
    padding: 16px 24px;
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-xl);
    display: flex;
    align-items: center;
    gap: 12px;
    opacity: 0;
    visibility: hidden;
    transition: var(--transition-slow);
    z-index: 2000;
}

.toast.show {
    transform: translateX(-50%) translateY(0);
    opacity: 1;
    visibility: visible;
}

.toast-icon {
    width: 32px;
    height: 32px;
    background: rgba(34, 197, 94, 0.1);
    border-radius: var(--radius-full);
    display: flex;
    align-items: center;
    justify-content: center;
    color: #16a34a;
}

.toast-icon svg {
    width: 18px;
    height: 18px;
}

.toast-message {
    font-size: 0.95rem;
    color: var(--text-primary);
    font-weight: 500;
}

/* ========================================
   响应式设计
   ======================================== */
@media (max-width: 1024px) {
    .features-grid {
        grid-template-columns: repeat(3, 1fr);
        gap: 24px;
    }

    .advantages-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .help-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .footer-main {
        grid-template-columns: 1fr;
        gap: 40px;
    }

    .footer-links {
        grid-template-columns: repeat(3, 1fr);
    }
}

@media (max-width: 768px) {
    .section {
        padding: 60px 0;
    }

    .nav-links,
    .nav-actions {
        display: none;
    }

    .mobile-menu-btn {
        display: flex;
        align-items: center;
        justify-content: center;
    }

    .hero {
        padding: 100px 0 60px;
    }

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

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

    .hero-actions {
        flex-direction: column;
        gap: 12px;
    }

    .hero-actions .btn {
        width: 100%;
    }

    .hero-stats {
        flex-direction: column;
        gap: 20px;
    }

    .stat-divider {
        width: 60px;
        height: 1px;
    }

    .features-grid,
    .advantages-grid {
        grid-template-columns: 1fr;
    }

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

    .generate-form {
        padding: 32px 24px;
    }

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

    .footer-links {
        grid-template-columns: 1fr;
        gap: 32px;
    }

    .footer-bottom {
        flex-direction: column;
        gap: 16px;
        text-align: center;
    }

    .carousel-btn {
        display: none;
    }

    .cta-box {
        padding: 60px 24px;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 16px;
    }

    .section-title {
        font-size: 1.5rem;
    }

    .feature-card,
    .advantage-item,
    .help-card {
        padding: 24px;
    }

    .radio-group {
        flex-direction: column;
    }

    .radio-label {
        width: 100%;
        justify-content: center;
    }
}

/* ========================================
   弹窗样式
   ======================================== */
.modal-overlay {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.6);
    backdrop-filter: blur(8px);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 3000;
    opacity: 0;
    visibility: hidden;
    transition: var(--transition-normal);
    padding: 24px;
}

.modal-overlay.show {
    opacity: 1;
    visibility: visible;
}

.modal {
    background: var(--bg-card);
    border-radius: var(--radius-xl);
    box-shadow: var(--shadow-xl);
    max-width: 500px;
    width: 100%;
    max-height: 90vh;
    overflow-y: auto;
    position: relative;
    transform: scale(0.9) translateY(20px);
    transition: var(--transition-slow);
}

.modal-overlay.show .modal {
    transform: scale(1) translateY(0);
}

.modal-close {
    position: absolute;
    top: 20px;
    right: 20px;
    width: 36px;
    height: 36px;
    border: none;
    background: var(--bg-primary);
    border-radius: var(--radius-full);
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--text-secondary);
    transition: var(--transition-normal);
    z-index: 10;
}

.modal-close:hover {
    background: var(--border-color);
    color: var(--text-primary);
}

.modal-close svg {
    width: 20px;
    height: 20px;
}

/* 登录注册弹窗 */
.auth-modal {
    padding: 48px 40px;
}

.auth-tabs {
    display: flex;
    gap: 8px;
    margin-bottom: 32px;
    background: var(--bg-primary);
    padding: 6px;
    border-radius: var(--radius-md);
}

.auth-tab {
    flex: 1;
    padding: 12px 24px;
    border: none;
    background: transparent;
    border-radius: var(--radius-sm);
    font-family: var(--font-body);
    font-size: 1rem;
    font-weight: 600;
    color: var(--text-secondary);
    cursor: pointer;
    transition: var(--transition-normal);
}

.auth-tab:hover {
    color: var(--text-primary);
}

.auth-tab.active {
    background: white;
    color: var(--accent-purple);
    box-shadow: var(--shadow-sm);
}

.auth-content {
    position: relative;
}

.auth-form {
    display: none;
}

.auth-form.active {
    display: block;
    animation: fadeIn 0.3s ease;
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(10px); }
    to { opacity: 1; transform: translateY(0); }
}

.auth-title {
    font-family: var(--font-heading);
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 8px;
}

.auth-subtitle {
    font-size: 0.95rem;
    color: var(--text-secondary);
    margin-bottom: 28px;
}

.auth-footer {
    text-align: center;
    margin-top: 24px;
    font-size: 0.9rem;
    color: var(--text-secondary);
}

.auth-footer a {
    color: var(--accent-purple);
    text-decoration: none;
    font-weight: 600;
}

.auth-footer a:hover {
    text-decoration: underline;
}

/* 首页生成确认弹窗 */
.confirm-modal {
    max-width: 700px;
    padding: 40px;
}

.confirm-header {
    text-align: center;
    margin-bottom: 32px;
}

.confirm-icon {
    width: 80px;
    height: 80px;
    background: var(--primary-gradient);
    border-radius: var(--radius-xl);
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 20px;
    color: white;
    animation: pulse 2s ease-in-out infinite;
}

@keyframes pulse {
    0%, 100% { transform: scale(1); }
    50% { transform: scale(1.05); }
}

.confirm-icon svg {
    width: 36px;
    height: 36px;
}

.confirm-title {
    font-family: var(--font-heading);
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 8px;
}

.confirm-subtitle {
    font-size: 1rem;
    color: var(--text-secondary);
}

/* 进度条 */
.progress-container {
    margin-bottom: 32px;
}

.progress-bar {
    width: 100%;
    height: 8px;
    background: var(--bg-primary);
    border-radius: var(--radius-full);
    overflow: hidden;
    margin-bottom: 12px;
}

.progress-fill {
    height: 100%;
    background: var(--primary-gradient);
    border-radius: var(--radius-full);
    width: 0%;
    transition: width 0.5s ease;
}

.progress-text {
    text-align: center;
    font-size: 0.9rem;
    color: var(--text-secondary);
    font-weight: 500;
}

/* 注意事项 */
.notes-container {
    background: var(--bg-primary);
    border-radius: var(--radius-lg);
    padding: 24px;
    margin-bottom: 24px;
}

.notes-title {
    display: flex;
    align-items: center;
    gap: 8px;
    font-family: var(--font-heading);
    font-size: 1.1rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 16px;
}

.notes-title svg {
    width: 20px;
    height: 20px;
    color: var(--accent-purple);
}

.notes-tabs {
    display: flex;
    gap: 8px;
    margin-bottom: 20px;
    flex-wrap: wrap;
}

.note-tab {
    padding: 8px 16px;
    border: none;
    background: white;
    border-radius: var(--radius-md);
    font-family: var(--font-body);
    font-size: 0.9rem;
    font-weight: 500;
    color: var(--text-secondary);
    cursor: pointer;
    transition: var(--transition-normal);
    border: 1px solid var(--border-color);
}

.note-tab:hover {
    border-color: var(--accent-blue);
    color: var(--accent-blue);
}

.note-tab.active {
    background: var(--primary-gradient);
    color: white;
    border-color: transparent;
}

.notes-content {
    position: relative;
}

.note-item {
    display: none;
}

.note-item.active {
    display: block;
    animation: fadeIn 0.3s ease;
}

.note-item h4 {
    display: flex;
    align-items: center;
    gap: 8px;
    font-size: 1rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 12px;
}

.note-item h4 svg {
    width: 18px;
    height: 18px;
    color: var(--accent-purple);
}

.note-item ul {
    list-style: none;
    padding: 0;
}

.note-item li {
    position: relative;
    padding-left: 24px;
    margin-bottom: 8px;
    font-size: 0.95rem;
    color: var(--text-secondary);
    line-height: 1.6;
}

.note-item li::before {
    content: '';
    position: absolute;
    left: 0;
    top: 8px;
    width: 6px;
    height: 6px;
    background: var(--accent-purple);
    border-radius: 50%;
}

/* 预览区域 */
.preview-container {
    margin-top: 24px;
}

.preview-title {
    display: flex;
    align-items: center;
    gap: 8px;
    font-family: var(--font-heading);
    font-size: 1.1rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 16px;
}

.preview-title svg {
    width: 20px;
    height: 20px;
    color: var(--accent-purple);
}

.preview-frame {
    background: var(--bg-primary);
    border-radius: var(--radius-lg);
    padding: 20px;
    margin-bottom: 24px;
}

.preview-mockup {
    background: white;
    border-radius: var(--radius-md);
    overflow: hidden;
    box-shadow: var(--shadow-md);
}

.mockup-header {
    background: #f1f5f9;
    padding: 12px 16px;
    display: flex;
    align-items: center;
    gap: 12px;
    border-bottom: 1px solid var(--border-color);
}

.mockup-dots {
    display: flex;
    gap: 6px;
}

.mockup-dots span {
    width: 12px;
    height: 12px;
    border-radius: 50%;
    background: #e2e8f0;
}

.mockup-dots span:first-child {
    background: #ef4444;
}

.mockup-dots span:nth-child(2) {
    background: #f59e0b;
}

.mockup-dots span:last-child {
    background: #22c55e;
}

.mockup-header span {
    font-size: 0.85rem;
    color: var(--text-secondary);
    font-weight: 500;
}

.mockup-content {
    padding: 40px;
    text-align: center;
}

.mockup-content h1 {
    font-family: var(--font-heading);
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 12px;
}

.mockup-content p {
    font-size: 1rem;
    color: var(--text-secondary);
    margin-bottom: 24px;
}

.mockup-features {
    display: flex;
    gap: 12px;
    justify-content: center;
    flex-wrap: wrap;
}

.mockup-features span {
    padding: 8px 16px;
    background: linear-gradient(135deg, rgba(102, 126, 234, 0.1) 0%, rgba(168, 85, 247, 0.1) 100%);
    border: 1px solid rgba(102, 126, 234, 0.2);
    border-radius: var(--radius-md);
    font-size: 0.85rem;
    color: var(--accent-purple);
    font-weight: 500;
}

.confirm-actions {
    display: flex;
    gap: 12px;
}

.confirm-actions .btn {
    flex: 1;
}