/* ===== 全局重置与变量 ===== */
:root {
    --primary: #07c160;
    --primary-dark: #06ad56;
    --secondary: #1a1a2e;
    --accent: #2d8cf0;
    --bg: #f0f4f8;
    --card-bg: #ffffff;
    --text: #1e293b;
    --text-light: #64748b;
    --shadow: 0 10px 40px rgba(0,0,0,0.08);
    --radius: 20px;
    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    --font: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: var(--font);
    background: var(--bg);
    color: var(--text);
    line-height: 1.6;
    overflow-x: hidden;
}

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

/* ===== 导航栏 ===== */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    z-index: 1000;
    background: rgba(255,255,255,0.85);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border-bottom: 1px solid rgba(0,0,0,0.05);
    transition: var(--transition);
}

.navbar.scrolled {
    background: rgba(255,255,255,0.95);
    box-shadow: 0 2px 20px rgba(0,0,0,0.06);
}

.nav-container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 72px;
}

.logo {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 1.4rem;
    font-weight: 700;
    color: var(--primary);
}

.logo i {
    font-size: 2rem;
    color: var(--primary);
}

.nav-links {
    display: flex;
    align-items: center;
    gap: 8px;
}

.nav-links a {
    text-decoration: none;
    color: var(--text);
    font-weight: 500;
    padding: 8px 18px;
    border-radius: 30px;
    transition: var(--transition);
    position: relative;
    font-size: 0.95rem;
}

.nav-links a:hover,
.nav-links a.active {
    background: var(--primary);
    color: #fff;
}

.nav-links a.admin-link {
    background: var(--secondary);
    color: #fff;
    padding: 8px 20px;
    border-radius: 30px;
}

.nav-links a.admin-link:hover {
    background: #2d2d4a;
}

/* 汉堡菜单 */
.hamburger {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 8px;
}

.hamburger span {
    display: block;
    width: 28px;
    height: 3px;
    background: var(--text);
    border-radius: 3px;
    transition: var(--transition);
}

/* ===== Hero 区 ===== */
.hero {
    padding: 140px 0 80px;
    background: linear-gradient(135deg, #f0f4f8 0%, #e2f0e9 100%);
    position: relative;
    overflow: hidden;
}

.hero::before {
    content: '';
    position: absolute;
    top: -50%;
    right: -20%;
    width: 600px;
    height: 600px;
    background: radial-gradient(circle, rgba(7,193,96,0.08) 0%, transparent 70%);
    border-radius: 50%;
    pointer-events: none;
}

.hero-content {
    display: flex;
    align-items: center;
    gap: 60px;
    position: relative;
    z-index: 1;
}

.hero-text {
    flex: 1;
}

.hero-text h1 {
    font-size: 3.2rem;
    font-weight: 800;
    line-height: 1.2;
    margin-bottom: 20px;
    letter-spacing: -0.5px;
}

.hero-text .highlight {
    color: var(--primary);
    position: relative;
}

.hero-text p {
    font-size: 1.15rem;
    color: var(--text-light);
    max-width: 540px;
    margin-bottom: 32px;
}

.hero-buttons {
    display: flex;
    gap: 16px;
    flex-wrap: wrap;
}

.btn {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 14px 32px;
    border-radius: 50px;
    font-weight: 600;
    font-size: 1rem;
    text-decoration: none;
    transition: var(--transition);
    border: none;
    cursor: pointer;
}

.btn-primary {
    background: var(--primary);
    color: #fff;
    box-shadow: 0 8px 24px rgba(7,193,96,0.3);
}

.btn-primary:hover {
    background: var(--primary-dark);
    transform: translateY(-2px);
    box-shadow: 0 12px 32px rgba(7,193,96,0.4);
}

.btn-outline {
    background: transparent;
    color: var(--text);
    border: 2px solid #e2e8f0;
}

.btn-outline:hover {
    border-color: var(--primary);
    color: var(--primary);
    background: rgba(7,193,96,0.05);
}

.hero-stats {
    display: flex;
    gap: 40px;
    margin-top: 40px;
}

.stat-item {
    display: flex;
    flex-direction: column;
}

.stat-num {
    font-size: 1.8rem;
    font-weight: 800;
    color: var(--secondary);
}

.stat-label {
    font-size: 0.9rem;
    color: var(--text-light);
}

.hero-image {
    flex: 1;
    display: flex;
    justify-content: center;
    align-items: center;
}

.phone-mockup {
    width: 240px;
    height: 420px;
    background: linear-gradient(145deg, #1a1a2e, #2d2d4a);
    border-radius: 36px;
    padding: 20px;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 20px;
    box-shadow: 0 30px 60px rgba(0,0,0,0.2);
    position: relative;
    border: 3px solid #333;
}

.phone-mockup .fa-weixin {
    font-size: 3rem;
    color: #fff;
    background: var(--primary);
    padding: 12px;
    border-radius: 16px;
}

.mockup-screen {
    width: 100%;
    flex: 1;
    background: #f0f4f8;
    border-radius: 16px;
    padding: 12px;
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.msg {
    height: 24px;
    border-radius: 12px;
    background: #d1d5db;
    opacity: 0.5;
}

.msg1 { width: 70%; background: var(--primary); opacity: 0.3; }
.msg2 { width: 50%; background: var(--accent); opacity: 0.2; }
.msg3 { width: 80%; background: #e5e7eb; }

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

.section-header h2 {
    font-size: 2.4rem;
    font-weight: 700;
    margin-bottom: 12px;
}

.section-header p {
    color: var(--text-light);
    font-size: 1.1rem;
}

/* ===== Features ===== */
.features {
    padding: 100px 0;
    background: #fff;
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 30px;
}

.feature-card {
    background: var(--card-bg);
    padding: 36px 28px;
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    text-align: center;
    transition: var(--transition);
    border: 1px solid rgba(0,0,0,0.04);
}

.feature-card:hover {
    transform: translateY(-8px);
    box-shadow: 0 20px 50px rgba(0,0,0,0.1);
}

.feature-card i {
    font-size: 2.6rem;
    color: var(--primary);
    margin-bottom: 20px;
    background: rgba(7,193,96,0.1);
    padding: 16px;
    border-radius: 20px;
}

.feature-card h3 {
    font-size: 1.3rem;
    margin-bottom: 12px;
}

.feature-card p {
    color: var(--text-light);
    font-size: 0.95rem;
}

/* ===== Download ===== */
.download {
    padding: 100px 0;
    background: var(--bg);
}

.download-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 30px;
}

.download-card {
    background: var(--card-bg);
    border-radius: var(--radius);
    padding: 32px 24px;
    box-shadow: var(--shadow);
    text-align: center;
    transition: var(--transition);
    border: 1px solid rgba(0,0,0,0.04);
}

.download-card:hover {
    transform: translateY(-6px);
    box-shadow: 0 16px 40px rgba(0,0,0,0.1);
}

.download-card .icon-wrap {
    width: 64px;
    height: 64px;
    margin: 0 auto 16px;
    background: rgba(7,193,96,0.08);
    border-radius: 20px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.download-card .icon-wrap i {
    font-size: 2.2rem;
    color: var(--primary);
}

.download-card h3 {
    font-size: 1.3rem;
    margin-bottom: 6px;
}

.download-card .version {
    color: var(--text-light);
    font-size: 0.9rem;
    margin-bottom: 4px;
}

.download-card .size {
    color: var(--text-light);
    font-size: 0.85rem;
    margin-bottom: 20px;
}

.download-card .btn {
    width: 100%;
    justify-content: center;
}

/* ===== FAQ ===== */
.faq {
    padding: 100px 0;
    background: #fff;
}

.faq-list {
    max-width: 800px;
    margin: 0 auto;
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.faq-item {
    background: var(--card-bg);
    border-radius: 16px;
    border: 1px solid #e2e8f0;
    overflow: hidden;
    transition: var(--transition);
}

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

.faq-question {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 20px 24px;
    font-weight: 600;
    cursor: pointer;
    user-select: none;
}

.faq-question i {
    transition: var(--transition);
    color: var(--text-light);
}

.faq-item.active .faq-question i {
    transform: rotate(180deg);
    color: var(--primary);
}

.faq-answer {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.35s ease, padding 0.35s ease;
    padding: 0 24px;
}

.faq-item.active .faq-answer {
    max-height: 200px;
    padding: 0 24px 20px;
}

.faq-answer p {
    color: var(--text-light);
    line-height: 1.7;
}

/* ===== 后台管理弹窗 ===== */
.admin-overlay {
    position: fixed;
    top: 0; left: 0; width: 100%; height: 100%;
    background: rgba(0,0,0,0.5);
    backdrop-filter: blur(4px);
    z-index: 2000;
    display: none;
    align-items: center;
    justify-content: center;
    padding: 20px;
}

.admin-overlay.show {
    display: flex;
}

.admin-modal {
    background: #fff;
    border-radius: 28px;
    padding: 40px 36px;
    max-width: 720px;
    width: 100%;
    max-height: 90vh;
    overflow-y: auto;
    box-shadow: 0 30px 80px rgba(0,0,0,0.2);
    position: relative;
    animation: modalIn 0.3s ease;
}

@keyframes modalIn {
    from { opacity: 0; transform: scale(0.92) translateY(20px); }
    to { opacity: 1; transform: scale(1) translateY(0); }
}

.admin-close {
    position: absolute;
    top: 16px;
    right: 20px;
    background: none;
    border: none;
    font-size: 2rem;
    color: var(--text-light);
    cursor: pointer;
}

.admin-modal h2 {
    margin-bottom: 24px;
    color: var(--secondary);
    display: flex;
    align-items: center;
    gap: 10px;
}

.form-group {
    margin-bottom: 16px;
}

.form-group label {
    display: block;
    font-weight: 600;
    margin-bottom: 6px;
    font-size: 0.95rem;
}

.form-group input {
    width: 100%;
    padding: 12px 16px;
    border: 2px solid #e2e8f0;
    border-radius: 12px;
    font-size: 1rem;
    transition: var(--transition);
    background: #f8fafc;
}

.form-group input:focus {
    outline: none;
    border-color: var(--primary);
    background: #fff;
}

.admin-error {
    color: #ef4444;
    margin-top: 12px;
    font-size: 0.9rem;
}

.admin-panel h3 {
    margin-bottom: 16px;
}

.admin-toolbar {
    margin-bottom: 16px;
}

.admin-table {
    width: 100%;
    border-collapse: collapse;
    margin-bottom: 20px;
}

.admin-table th, .admin-table td {
    padding: 12px 10px;
    text-align: left;
    border-bottom: 1px solid #e2e8f0;
    font-size: 0.9rem;
}

.admin-table th {
    font-weight: 600;
    color: var(--text-light);
    background: #f8fafc;
}

.admin-table td {
    color: var(--text);
}

.admin-table .btn-sm {
    padding: 6px 14px;
    font-size: 0.8rem;
    border-radius: 8px;
    border: none;
    cursor: pointer;
    transition: var(--transition);
}

.btn-edit {
    background: var(--accent);
    color: #fff;
    margin-right: 6px;
}

.btn-edit:hover {
    background: #1d7ad8;
}

.btn-delete {
    background: #ef4444;
    color: #fff;
}

.btn-delete:hover {
    background: #dc2626;
}

.admin-form {
    background: #f8fafc;
    padding: 24px;
    border-radius: 16px;
    margin-top: 16px;
}

.admin-form h4 {
    margin-bottom: 16px;
}

.form-actions {
    display: flex;
    gap: 12px;
    margin-top: 12px;
}

/* ===== 页脚 ===== */
.footer {
    background: var(--secondary);
    color: #fff;
    padding: 48px 0 32px;
    text-align: center;
}

.footer-brand {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
    font-size: 1.5rem;
    font-weight: 700;
    margin-bottom: 12px;
}

.footer-brand i {
    color: var(--primary);
}

.footer-text {
    color: rgba(255,255,255,0.6);
    max-width: 500px;
    margin: 0 auto 16px;
}

.footer-copy {
    color: rgba(255,255,255,0.4);
    font-size: 0.85rem;
}

/* ===== 响应式设计 ===== */
@media (max-width: 992px) {
    .hero-content {
        flex-direction: column;
        text-align: center;
    }
    .hero-text h1 {
        font-size: 2.6rem;
    }
    .hero-text p {
        margin: 0 auto 32px;
    }
    .hero-buttons {
        justify-content: center;
    }
    .hero-stats {
        justify-content: center;
    }
    .features-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 768px) {
    .nav-links {
        position: fixed;
        top: 72px;
        left: 0;
        width: 100%;
        background: rgba(255,255,255,0.98);
        flex-direction: column;
        padding: 20px 24px;
        gap: 6px;
        box-shadow: 0 10px 30px rgba(0,0,0,0.08);
        transform: translateY(-120%);
        transition: transform 0.4s ease;
        border-radius: 0 0 24px 24px;
    }
    .nav-links.open {
        transform: translateY(0);
    }
    .nav-links a {
        width: 100%;
        text-align: center;
        padding: 14px;
    }
    .hamburger {
        display: flex;
    }
    .hero {
        padding: 120px 0 60px;
    }
    .hero-text h1 {
        font-size: 2rem;
    }
    .hero-stats {
        gap: 20px;
        flex-wrap: wrap;
    }
    .features-grid {
        grid-template-columns: 1fr;
    }
    .download-grid {
        grid-template-columns: 1fr;
    }
    .admin-modal {
        padding: 28px 20px;
    }
    .admin-table {
        font-size: 0.8rem;
    }
    .admin-table th, .admin-table td {
        padding: 8px 6px;
    }
}

@media (max-width: 480px) {
    .hero-text h1 {
        font-size: 1.8rem;
    }
    .section-header h2 {
        font-size: 1.8rem;
    }
    .btn {
        padding: 12px 24px;
        font-size: 0.9rem;
    }
    .phone-mockup {
        width: 180px;
        height: 320px;
    }
}