/* ============================================
   轻聊 · 简约微信概念站 样式
   ============================================ */

/* ----- 变量 & 重置 ----- */
:root {
    --primary: #07c160;
    --primary-dark: #06ad54;
    --primary-light: #e8f8ee;
    --bg: #f9fafb;
    --card-bg: #ffffff;
    --text: #1e293b;
    --text-secondary: #64748b;
    --border: #e2e8f0;
    --shadow: 0 8px 30px rgba(0,0,0,0.06);
    --shadow-hover: 0 16px 48px rgba(0,0,0,0.10);
    --radius: 18px;
    --radius-sm: 12px;
    --transition: 0.25s cubic-bezier(0.4,0,0.2,1);
    --font: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
}

*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }
body {
    font-family: var(--font);
    background: var(--bg);
    color: var(--text);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
}
a { text-decoration: none; color: inherit; }
ul { list-style: none; }
img { max-width: 100%; display: block; }
.container { max-width: 1200px; margin: 0 auto; padding: 0 24px; }

/* ----- 导航栏 ----- */
.navbar {
    position: fixed; top: 0; left: 0; width: 100%;
    background: rgba(255,255,255,0.72);
    backdrop-filter: blur(16px) saturate(180%);
    -webkit-backdrop-filter: blur(16px) saturate(180%);
    border-bottom: 1px solid rgba(226,232,240,0.5);
    z-index: 1000;
    transition: box-shadow var(--transition);
}
.navbar.scrolled { box-shadow: 0 4px 20px rgba(0,0,0,0.06); }
.nav-container {
    display: flex; align-items: center; justify-content: space-between;
    height: 64px;
}
.nav-left { display: flex; align-items: center; gap: 32px; }
.logo {
    display: flex; align-items: center; gap: 8px;
    font-size: 1.35rem; font-weight: 700; letter-spacing: -0.3px;
}
.logo i { font-size: 1.6rem; }
.nav-links { display: flex; gap: 8px; }
.nav-links li a {
    padding: 8px 16px; border-radius: 40px; font-weight: 500;
    font-size: 0.95rem; color: var(--text-secondary);
    transition: all var(--transition); position: relative;
}
.nav-links li a:hover,
.nav-links li a.active { background: var(--primary-light); color: var(--primary); }
.nav-right { display: flex; align-items: center; gap: 12px; }
.btn-admin {
    padding: 8px 18px; border-radius: 40px; background: transparent;
    border: 1.5px solid var(--border); font-weight: 500; font-size: 0.9rem;
    color: var(--text-secondary); transition: all var(--transition);
}
.btn-admin:hover { border-color: var(--primary); color: var(--primary); background: var(--primary-light); }
.hamburger {
    display: none; flex-direction: column; gap: 5px;
    background: none; border: none; cursor: pointer; padding: 6px;
}
.hamburger span {
    display: block; width: 24px; height: 2.5px; background: var(--text);
    border-radius: 4px; transition: all var(--transition);
}

/* ----- Hero ----- */
.hero {
    padding: 140px 0 80px; background: linear-gradient(145deg, #f0fdf4 0%, #ffffff 100%);
    overflow: hidden;
}
.hero-content {
    display: flex; align-items: center; gap: 60px;
}
.hero-text { flex: 1; }
.hero-text h1 {
    font-size: 3.2rem; font-weight: 700; line-height: 1.2; letter-spacing: -1px;
    margin-bottom: 16px;
}
.highlight { background: linear-gradient(135deg, #07c160, #10b981); -webkit-background-clip: text; -webkit-text-fill-color: transparent; background-clip: text; }
.hero-text p { font-size: 1.15rem; color: var(--text-secondary); max-width: 540px; margin-bottom: 28px; }
.hero-buttons { display: flex; gap: 14px; flex-wrap: wrap; margin-bottom: 32px; }
.btn-primary, .btn-secondary {
    display: inline-flex; align-items: center; gap: 8px;
    padding: 14px 32px; border-radius: 60px; font-weight: 600; font-size: 1rem;
    transition: all var(--transition); border: none; cursor: pointer;
}
.btn-primary { background: var(--primary); color: #fff; box-shadow: 0 6px 20px rgba(7,193,96,0.3); }
.btn-primary:hover { background: var(--primary-dark); transform: translateY(-2px); box-shadow: 0 8px 28px rgba(7,193,96,0.35); }
.btn-secondary { background: #fff; color: var(--text); border: 1.5px solid var(--border); }
.btn-secondary:hover { border-color: var(--primary); color: var(--primary); transform: translateY(-2px); }
.hero-stats { display: flex; gap: 28px; flex-wrap: wrap; }
.hero-stats span { font-size: 0.95rem; color: var(--text-secondary); }
.hero-stats strong { color: var(--text); font-weight: 700; }

/* 手机模型 */
.hero-phone { flex: 0 0 320px; }
.phone-mock {
    background: #1e293b; border-radius: 40px; padding: 12px;
    box-shadow: 0 30px 60px rgba(0,0,0,0.15); transform: rotate(2deg);
}
.phone-screen {
    background: #fff; border-radius: 30px; padding: 16px; min-height: 480px;
    overflow: hidden;
}
.phone-header { font-weight: 700; padding-bottom: 12px; border-bottom: 1px solid var(--border); margin-bottom: 12px; display: flex; align-items: center; gap: 6px; color: var(--primary); }
.msg-list { display: flex; flex-direction: column; gap: 16px; }
.msg-item { display: flex; align-items: center; gap: 12px; }
.avatar {
    width: 44px; height: 44px; border-radius: 50%; flex-shrink: 0;
}
.g1 { background: linear-gradient(135deg, #f472b6, #ec4899); }
.g2 { background: linear-gradient(135deg, #60a5fa, #3b82f6); }
.g3 { background: linear-gradient(135deg, #34d399, #10b981); }
.g4 { background: linear-gradient(135deg, #fbbf24, #f59e0b); }
.msg-info strong { font-size: 0.9rem; display: block; }
.msg-info p { font-size: 0.8rem; color: var(--text-secondary); margin: 0; }

/* ----- 通用 Section ----- */
section { padding: 80px 0; }
.section-title { text-align: center; margin-bottom: 48px; }
.section-title h2 { font-size: 2.2rem; font-weight: 700; letter-spacing: -0.5px; }
.section-title p { color: var(--text-secondary); font-size: 1.05rem; margin-top: 8px; }

/* ----- 功能卡片 ----- */
.features { background: #fff; }
.features-grid {
    display: grid; grid-template-columns: repeat(3,1fr); gap: 28px;
}
.feature-card {
    background: var(--card-bg); border-radius: var(--radius); padding: 32px 24px;
    border: 1px solid var(--border); transition: all var(--transition);
    text-align: center;
}
.feature-card:hover { transform: translateY(-8px); box-shadow: var(--shadow-hover); border-color: transparent; }
.icon-wrap {
    width: 64px; height: 64px; border-radius: 20px; background: var(--primary-light);
    display: flex; align-items: center; justify-content: center;
    margin: 0 auto 18px; font-size: 1.8rem; color: var(--primary);
}
.feature-card h3 { font-size: 1.2rem; font-weight: 600; margin-bottom: 8px; }
.feature-card p { color: var(--text-secondary); font-size: 0.95rem; }

/* ----- 朋友圈 ----- */
.moments { background: var(--bg); }
.moments-grid {
    display: grid; grid-template-columns: repeat(3,1fr); gap: 24px;
}
.moment-card {
    background: var(--card-bg); border-radius: var(--radius); overflow: hidden;
    border: 1px solid var(--border); transition: all var(--transition);
}
.moment-card:hover { transform: translateY(-6px); box-shadow: var(--shadow-hover); }
.moment-card .moment-images {
    display: grid; grid-template-columns: repeat(3,1fr); gap: 4px;
    max-height: 240px; overflow: hidden;
}
.moment-card .moment-images img {
    width: 100%; height: 100%; object-fit: cover; aspect-ratio: 1/1;
}
.moment-card .moment-body { padding: 18px 20px; }
.moment-card .moment-author { display: flex; align-items: center; gap: 12px; margin-bottom: 10px; }
.moment-card .moment-avatar {
    width: 40px; height: 40px; border-radius: 50%; display: flex;
    align-items: center; justify-content: center; color: #fff; font-weight: 700; font-size: 0.9rem;
}
.moment-card .moment-author strong { font-size: 0.95rem; }
.moment-card .moment-text { color: var(--text-secondary); font-size: 0.95rem; margin-bottom: 10px; }
.moment-card .moment-time { font-size: 0.8rem; color: #94a3b8; }
.moments-more { text-align: center; margin-top: 40px; }
.btn-outline {
    display: inline-flex; align-items: center; gap: 8px;
    padding: 12px 32px; border-radius: 60px; border: 1.5px solid var(--border);
    font-weight: 500; transition: all var(--transition);
}
.btn-outline:hover { border-color: var(--primary); color: var(--primary); }

/* ----- 联系表单 ----- */
.contact { background: #fff; }
.contact-wrapper {
    display: grid; grid-template-columns: 1.4fr 1fr; gap: 48px;
}
.contact-form .form-row { display: flex; gap: 16px; margin-bottom: 16px; }
.contact-form input, .contact-form textarea {
    width: 100%; padding: 14px 18px; border-radius: var(--radius-sm);
    border: 1.5px solid var(--border); font-size: 0.95rem; font-family: var(--font);
    transition: border var(--transition); background: var(--bg);
}
.contact-form input:focus, .contact-form textarea:focus {
    outline: none; border-color: var(--primary); box-shadow: 0 0 0 3px rgba(7,193,96,0.1);
}
.btn-submit { margin-top: 16px; }
.form-feedback { margin-top: 12px; font-size: 0.9rem; min-height: 24px; }
.form-feedback.success { color: var(--primary); }
.form-feedback.error { color: #ef4444; }
.contact-info { display: flex; flex-direction: column; gap: 20px; padding: 28px 0; }
.info-item { display: flex; align-items: center; gap: 14px; font-size: 1rem; color: var(--text-secondary); }
.info-item i { width: 40px; height: 40px; border-radius: 50%; background: var(--primary-light); display: flex; align-items: center; justify-content: center; color: var(--primary); font-size: 1.1rem; }

/* ----- 页脚 ----- */
.footer {
    background: #0f172a; color: #cbd5e1; padding: 48px 0 24px;
}
.footer-content {
    display: flex; justify-content: space-between; align-items: center; flex-wrap: wrap; gap: 20px;
    padding-bottom: 24px; border-bottom: 1px solid #1e293b;
}
.footer-brand { display: flex; align-items: center; gap: 10px; font-weight: 600; font-size: 1.1rem; }
.footer-links { display: flex; gap: 20px; flex-wrap: wrap; }
.footer-links a { font-size: 0.9rem; transition: color var(--transition); }
.footer-links a:hover { color: var(--primary); }
.footer-social { display: flex; gap: 14px; }
.footer-social a {
    width: 40px; height: 40px; border-radius: 50%; background: #1e293b;
    display: flex; align-items: center; justify-content: center; transition: all var(--transition);
}
.footer-social a:hover { background: var(--primary); color: #fff; }
.footer-bottom { text-align: center; padding-top: 24px; font-size: 0.85rem; color: #64748b; }

/* ----- 回到顶部 ----- */
.back-to-top {
    position: fixed; bottom: 32px; right: 32px; width: 48px; height: 48px;
    border-radius: 50%; background: var(--primary); color: #fff; border: none;
    font-size: 1.2rem; cursor: pointer; box-shadow: 0 6px 20px rgba(7,193,96,0.3);
    transition: all var(--transition); opacity: 0; transform: scale(0.8); pointer-events: none;
    z-index: 999;
}
.back-to-top.visible { opacity: 1; transform: scale(1); pointer-events: auto; }
.back-to-top:hover { background: var(--primary-dark); transform: scale(1.05); }

/* ============================================
   后台管理样式
   ============================================ */
.admin-body { background: #f1f5f9; min-height: 100vh; }
.admin-login {
    display: flex; align-items: center; justify-content: center;
    min-height: 100vh; padding: 24px;
    background: linear-gradient(145deg, #f0fdf4, #e8f8ee);
}
.login-card {
    background: #fff; border-radius: 28px; padding: 48px 36px;
    max-width: 420px; width: 100%; box-shadow: 0 20px 60px rgba(0,0,0,0.06);
    text-align: center;
}
.login-logo i { font-size: 3.2rem; color: var(--primary); margin-bottom: 8px; }
.login-card h2 { font-size: 1.8rem; font-weight: 700; }
.login-sub { color: var(--text-secondary); margin-bottom: 28px; }
.input-group {
    display: flex; align-items: center; background: var(--bg);
    border-radius: var(--radius-sm); padding: 0 16px;
    border: 1.5px solid var(--border); margin-bottom: 16px; transition: border var(--transition);
}
.input-group:focus-within { border-color: var(--primary); }
.input-group i { color: var(--text-secondary); font-size: 1rem; }
.input-group input {
    width: 100%; padding: 14px 12px; border: none; background: transparent;
    font-size: 0.95rem; font-family: var(--font); outline: none;
}
.btn-full { width: 100%; justify-content: center; }
.login-error { color: #ef4444; font-size: 0.9rem; margin-top: 12px; min-height: 24px; }

/* 管理面板 */
.admin-panel { min-height: 100vh; display: flex; flex-direction: column; }
.admin-header {
    background: #fff; border-bottom: 1px solid var(--border);
    padding: 0 24px; box-shadow: 0 2px 12px rgba(0,0,0,0.04);
}
.admin-header-inner {
    max-width: 1400px; margin: 0 auto; display: flex;
    justify-content: space-between; align-items: center; height: 64px;
}
.admin-header-inner h2 { font-size: 1.3rem; display: flex; align-items: center; gap: 8px; }
.btn-logout {
    padding: 8px 20px; border-radius: 40px; border: 1.5px solid var(--border);
    background: none; font-weight: 500; cursor: pointer; transition: all var(--transition);
    display: flex; align-items: center; gap: 6px;
}
.btn-logout:hover { border-color: #ef4444; color: #ef4444; }
.admin-content { display: flex; flex: 1; max-width: 1400px; margin: 0 auto; width: 100%; }
.admin-sidebar {
    width: 220px; background: #fff; border-right: 1px solid var(--border);
    padding: 24px 0; flex-shrink: 0;
}
.admin-sidebar ul li {
    padding: 14px 24px; cursor: pointer; display: flex; align-items: center; gap: 12px;
    font-weight: 500; color: var(--text-secondary); transition: all var(--transition);
    border-left: 3px solid transparent;
}
.admin-sidebar ul li.active, .admin-sidebar ul li:hover {
    background: var(--primary-light); color: var(--primary); border-left-color: var(--primary);
}
.admin-main { flex: 1; padding: 32px; overflow-x: auto; }
.admin-tab { display: none; }
.admin-tab.active { display: block; }
.tab-header { display: flex; justify-content: space-between; align-items: center; margin-bottom: 24px; flex-wrap: wrap; gap: 12px; }
.badge {
    background: var(--primary-light); color: var(--primary); padding: 2px 12px;
    border-radius: 40px; font-size: 0.8rem; font-weight: 600; margin-left: 8px;
}
.btn-sm { padding: 10px 20px; font-size: 0.9rem; }
.table-responsive { overflow-x: auto; }
.admin-table {
    width: 100%; border-collapse: collapse; background: #fff;
    border-radius: var(--radius-sm); overflow: hidden; box-shadow: 0 2px 12px rgba(0,0,0,0.04);
}
.admin-table th, .admin-table td {
    padding: 14px 18px; text-align: left; border-bottom: 1px solid var(--border); font-size: 0.9rem;
}
.admin-table th { background: #f8fafc; font-weight: 600; color: var(--text-secondary); }
.admin-table td { color: var(--text); }
.admin-table .avatar-mini { width: 32px; height: 32px; border-radius: 50%; display: inline-flex; align-items: center; justify-content: center; color: #fff; font-weight: 700; font-size: 0.75rem; }
.btn-icon { background: none; border: none; cursor: pointer; font-size: 1.1rem; padding: 4px 8px; border-radius: 8px; transition: all var(--transition); }
.btn-icon.edit { color: #3b82f6; }
.btn-icon.delete { color: #ef4444; }
.btn-icon:hover { background: var(--bg); }
.empty-tip { text-align: center; color: var(--text-secondary); padding: 40px 0; font-size: 0.95rem; }

/* 弹窗 */
.modal-overlay {
    display: none; position: fixed; inset: 0; background: rgba(0,0,0,0.4);
    backdrop-filter: blur(4px); z-index: 2000;
    align-items: center; justify-content: center; padding: 24px;
}
.modal-overlay.active { display: flex; }
.modal-card {
    background: #fff; border-radius: 24px; max-width: 520px; width: 100%;
    padding: 32px 28px; box-shadow: 0 30px 60px rgba(0,0,0,0.12);
    animation: fadeUp 0.25s ease;
}
@keyframes fadeUp { from { opacity: 0; transform: translateY(20px); } to { opacity: 1; transform: translateY(0); } }
.modal-header { display: flex; justify-content: space-between; align-items: center; margin-bottom: 20px; }
.modal-close { background: none; border: none; font-size: 2rem; cursor: pointer; color: var(--text-secondary); line-height: 1; }
.form-group { margin-bottom: 18px; }
.form-group label { display: block; font-weight: 500; margin-bottom: 6px; font-size: 0.9rem; }
.form-group input, .form-group textarea {
    width: 100%; padding: 12px 14px; border-radius: var(--radius-sm);
    border: 1.5px solid var(--border); font-size: 0.95rem; font-family: var(--font);
    transition: border var(--transition); background: var(--bg);
}
.form-group input:focus, .form-group textarea:focus { border-color: var(--primary); outline: none; }

/* ============================================
   响应式
   ============================================ */
@media (max-width: 1024px) {
    .features-grid { grid-template-columns: repeat(2,1fr); }
    .moments-grid { grid-template-columns: repeat(2,1fr); }
    .hero-content { flex-direction: column; text-align: center; }
    .hero-text p { margin: 0 auto 28px; }
    .hero-buttons, .hero-stats { justify-content: center; }
    .hero-phone { flex: unset; max-width: 280px; }
}
@media (max-width: 768px) {
    .nav-links { display: none; position: absolute; top: 64px; left: 0; width: 100%; background: rgba(255,255,255,0.98); backdrop-filter: blur(16px); flex-direction: column; padding: 16px 24px; border-bottom: 1px solid var(--border); }
    .nav-links.open { display: flex; }
    .hamburger { display: flex; }
    .hero-text h1 { font-size: 2.4rem; }
    .features-grid { grid-template-columns: 1fr; }
    .moments-grid { grid-template-columns: 1fr; }
    .contact-wrapper { grid-template-columns: 1fr; }
    .contact-form .form-row { flex-direction: column; }
    .footer-content { flex-direction: column; text-align: center; }
    .admin-content { flex-direction: column; }
    .admin-sidebar { width: 100%; border-right: none; border-bottom: 1px solid var(--border); padding: 12px 0; display: flex; overflow-x: auto; }
    .admin-sidebar ul { display: flex; padding: 0 16px; }
    .admin-sidebar ul li { white-space: nowrap; border-left: none; border-bottom: 3px solid transparent; padding: 12px 16px; }
    .admin-sidebar ul li.active { border-left: none; border-bottom-color: var(--primary); }
    .admin-main { padding: 20px 16px; }
}
@media (max-width: 480px) {
    .hero-text h1 { font-size: 1.9rem; }
    .hero-stats { flex-direction: column; align-items: center; gap: 8px; }
    .btn-primary, .btn-secondary { width: 100%; justify-content: center; }
    .back-to-top { bottom: 20px; right: 20px; width: 44px; height: 44px; }
}