/* ============================================
   交流平台  —  主样式表
   ============================================ */

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

:root {
    --primary: #4f8a8b;
    --primary-dark: #3a6b6c;
    --accent: #f0a04b;
    --bg: #f5f3ef;
    --white: #ffffff;
    --gray-100: #f7f7f5;
    --gray-200: #e8e6e1;
    --gray-500: #8b8b83;
    --gray-700: #4a4a42;
    --gray-900: #2c2c26;
    --danger: #d35d5d;
    --shadow-sm: 0 1px 3px rgba(0,0,0,.06);
    --shadow: 0 2px 12px rgba(0,0,0,.08);
    --shadow-lg: 0 8px 30px rgba(0,0,0,.12);
    --radius: 10px;
    --radius-sm: 6px;
    --transition: .25s ease;
    --max-width: 1100px;
}

html { scroll-behavior: smooth; }
body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
                 "Microsoft YaHei", "Helvetica Neue", sans-serif;
    background: var(--bg);
    color: var(--gray-900);
    line-height: 1.7;
    min-height: 100vh;
}

/* ---------- 页面背景图层 ---------- */
.bg-layer {
    position: fixed; inset: 0; z-index: -1;
    background-size: cover; background-position: center;
    background-repeat: no-repeat;
}
.bg-layer::after {
    content: ''; position: absolute; inset: 0;
    background: rgba(245, 243, 239, 0.78);
}

a { text-decoration: none; color: var(--primary); }
a:hover { color: var(--primary-dark); }
img { max-width: 100%; display: block; }
button { cursor: pointer; font-family: inherit; }
input, textarea, select { font-family: inherit; }

/* ---------- 导航栏 ---------- */
.navbar {
    position: sticky; top: 0; z-index: 1000;
    display: flex; align-items: center; justify-content: space-between;
    background: rgba(255,255,255,.92);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    padding: 0 32px; height: 60px;
    box-shadow: 0 1px 6px rgba(0,0,0,.06);
}
.nav-left { display: flex; align-items: center; gap: 28px; }
.nav-logo { display: flex; align-items: center; gap: 10px; }
.nav-logo img { height: 36px; border-radius: 6px; }
.nav-logo .blog-name {
    font-size: 1.2rem; font-weight: 700; color: var(--gray-900);
    letter-spacing: 1px;
}
.nav-menu { list-style: none; display: flex; gap: 4px; }
.nav-menu > li { position: relative; }
.nav-menu > li > a {
    display: block; padding: 8px 16px; border-radius: var(--radius-sm);
    color: var(--gray-700); font-size: .92rem; transition: var(--transition);
}
.nav-menu > li > a:hover,
.nav-menu > li > a.active { background: var(--gray-100); color: var(--primary); }

.dropdown .submenu {
    display: none; position: absolute; top: 100%; left: 0; min-width: 150px;
    background: var(--white); border-radius: var(--radius-sm);
    box-shadow: var(--shadow-lg); padding: 6px 0; overflow: hidden;
}
.dropdown:hover .submenu { display: block; }
.submenu li a {
    display: block; padding: 9px 20px; color: var(--gray-700);
    font-size: .88rem; transition: var(--transition);
}
.submenu li a:hover { background: var(--gray-100); color: var(--primary); }

.nav-right { display: flex; gap: 8px; }
.nav-right a {
    padding: 7px 18px; border-radius: var(--radius-sm);
    font-size: .88rem; color: var(--gray-700); transition: var(--transition);
}
.nav-right a:hover { background: var(--gray-100); }
.nav-right .btn-nav {
    background: var(--primary); color: #fff;
}
.nav-right .btn-nav:hover { background: var(--primary-dark); }

.hamburger { display: none; background: none; border: none; font-size: 1.6rem; color: var(--gray-700); }

/* ---------- Hero 横幅（首页） ---------- */
.hero {
    position: relative; height: 380px; display: flex; align-items: center; justify-content: center;
    background: url('../images/banner.jpg') center/cover no-repeat;
    overflow: hidden;
}
.hero::before {
    content: ''; position: absolute; inset: 0;
    background: linear-gradient(180deg, rgba(0,0,0,.35), rgba(0,0,0,.15));
}
.hero-content {
    position: relative; text-align: center; color: #fff; z-index: 1;
    max-width: 640px; padding: 0 20px;
}
.hero-content h1 { font-size: 2.6rem; font-weight: 700; margin-bottom: 12px; letter-spacing: 2px; }
.hero-content p { font-size: 1.1rem; opacity: .9; }

/* ---------- 页面横幅（各模块通用） ---------- */
.page-hero {
    height: 220px; display: flex; align-items: center; justify-content: center;
    background-size: cover; background-position: center; background-repeat: no-repeat;
    position: relative; overflow: hidden;
}
.page-hero::before {
    content: ''; position: absolute; inset: 0;
    background: linear-gradient(135deg, rgba(0,0,0,.5), rgba(0,0,0,.25));
}
.page-hero-content {
    position: relative; text-align: center; color: #fff; z-index: 1;
}
.page-hero-content h2 { font-size: 1.8rem; font-weight: 700; letter-spacing: 2px; }
.page-hero-content p { font-size: .95rem; opacity: .85; margin-top: 6px; }

/* ---------- 容器 ---------- */
.container { max-width: var(--max-width); margin: 0 auto; padding: 32px 20px; }
.container-wide { max-width: 1300px; margin: 0 auto; padding: 32px 20px; }

/* ---------- 卡片 ---------- */
.card {
    background: var(--white); border-radius: var(--radius);
    padding: 28px; margin-bottom: 20px;
    box-shadow: var(--shadow-sm); transition: var(--transition);
}
.card:hover { box-shadow: var(--shadow); transform: translateY(-2px); }
.card-title { font-size: 1.25rem; font-weight: 600; margin-bottom: 10px; }
.card-title a { color: var(--gray-900); }
.card-title a:hover { color: var(--primary); }
.card-meta {
    display: flex; flex-wrap: wrap; gap: 16px;
    font-size: .82rem; color: var(--gray-500); margin-bottom: 14px;
}
.card-meta span { display: flex; align-items: center; gap: 5px; }
.card-summary { color: var(--gray-700); font-size: .94rem; line-height: 1.8; }
.card-actions {
    display: flex; gap: 18px; margin-top: 18px; padding-top: 16px;
    border-top: 1px solid var(--gray-200);
}
.card-actions button {
    background: none; border: none; font-size: .88rem; color: var(--gray-500);
    display: flex; align-items: center; gap: 6px; transition: var(--transition);
    padding: 4px 0;
}
.card-actions button:hover { color: var(--primary); }
.card-actions button.loved { color: var(--danger); }
.card-actions button.saved { color: var(--accent); }

/* ---------- 分页 ---------- */
.pagination-area { display: flex; justify-content: center; gap: 4px; margin: 30px 0; }
.pagination-area button {
    min-width: 38px; height: 38px; border: 1px solid var(--gray-200);
    background: var(--white); border-radius: var(--radius-sm);
    font-size: .88rem; color: var(--gray-700); transition: var(--transition);
}
.pagination-area button:hover:not(.active) {
    border-color: var(--primary); color: var(--primary);
}
.pagination-area button.active {
    background: var(--primary); color: #fff; border-color: var(--primary);
}

/* ---------- 文章详情 ---------- */
.detail-header { margin-bottom: 24px; }
.detail-header h1 { font-size: 1.8rem; font-weight: 700; margin-bottom: 14px; }
.detail-content {
    font-size: 1.05rem; line-height: 2; color: var(--gray-700);
    word-break: break-word;
}
.detail-content img { max-width: 100%; border-radius: var(--radius-sm); margin: 16px 0; }
.detail-content p { margin-bottom: 16px; }

.comment-section { margin-top: 40px; }
.comment-item {
    background: var(--white); border-radius: var(--radius-sm);
    padding: 18px; margin-bottom: 12px; box-shadow: var(--shadow-sm);
    display: flex; gap: 14px;
}
.comment-avatar { width: 42px; height: 42px; border-radius: 50%; object-fit: cover; flex-shrink: 0; }
.comment-body { flex: 1; }
.comment-user { font-weight: 600; font-size: .9rem; margin-bottom: 4px; }
.comment-text { font-size: .92rem; color: var(--gray-700); }
.comment-time { font-size: .78rem; color: var(--gray-500); margin-top: 6px; }

/* ---------- 用户中心 ---------- */
.center-container { display: flex; gap: 28px; }
.sidebar {
    width: 220px; flex-shrink: 0;
    background: var(--white); border-radius: var(--radius);
    padding: 20px 0; box-shadow: var(--shadow-sm);
}
.menu-list { list-style: none; }
.menu-item a {
    display: block; padding: 12px 24px; color: var(--gray-700);
    font-size: .92rem; transition: var(--transition);
    border-left: 3px solid transparent;
}
.menu-item a:hover,
.menu-item.active a {
    color: var(--primary); background: var(--gray-100);
    border-left-color: var(--primary);
}
.content-area { flex: 1; min-width: 0; }

/* ---------- 登录 / 注册 ---------- */
.auth-container {
    display: flex; justify-content: center; align-items: center;
    min-height: calc(100vh - 60px); padding: 40px 20px;
}
.auth-card {
    background: rgba(255,255,255,.95);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    border-radius: 14px; padding: 40px 36px; width: 100%; max-width: 420px;
    box-shadow: var(--shadow-lg);
}
.auth-card h2 { text-align: center; font-size: 1.5rem; font-weight: 700; margin-bottom: 28px; color: var(--gray-900); }
.auth-tabs { display: flex; gap: 0; margin-bottom: 24px; border-bottom: 1px solid var(--gray-200); }
.auth-tabs button {
    flex: 1; padding: 10px; border: none; background: none;
    font-size: .92rem; color: var(--gray-500); transition: var(--transition);
    border-bottom: 2px solid transparent;
}
.auth-tabs button.active { color: var(--primary); border-bottom-color: var(--primary); font-weight: 600; }

.form-group { margin-bottom: 18px; }
.form-group label { display: block; font-size: .84rem; font-weight: 500; color: var(--gray-700); margin-bottom: 6px; }
.form-group input,
.form-group textarea,
.form-group select {
    width: 100%; padding: 11px 14px; border: 1px solid var(--gray-200);
    border-radius: var(--radius-sm); font-size: .94rem; transition: var(--transition);
    background: var(--white);
}
.form-group input:focus,
.form-group textarea:focus { outline: none; border-color: var(--primary); box-shadow: 0 0 0 3px rgba(79,138,139,.15); }

.code-row { display: flex; gap: 10px; }
.code-row input { flex: 1; }
.code-row button {
    white-space: nowrap; padding: 10px 16px; background: var(--gray-100);
    border: 1px solid var(--gray-200); border-radius: var(--radius-sm);
    font-size: .85rem; color: var(--gray-700); transition: var(--transition);
}
.code-row button:hover { background: var(--gray-200); }

.btn {
    display: inline-block; padding: 11px 28px; border: none; border-radius: var(--radius-sm);
    font-size: .94rem; font-weight: 500; transition: var(--transition); text-align: center;
}
.btn-primary { background: var(--primary); color: #fff; }
.btn-primary:hover { background: var(--primary-dark); }
.btn-block { display: block; width: 100%; }
.btn-sm { padding: 6px 16px; font-size: .84rem; }
.btn-danger { background: var(--danger); color: #fff; }
.btn-danger:hover { opacity: .85; }
.btn-outline { background: transparent; border: 1px solid var(--gray-200); color: var(--gray-700); }
.btn-outline:hover { border-color: var(--primary); color: var(--primary); }

/* ---------- Flash 消息 ---------- */
.flash-msg {
    padding: 12px 18px; border-radius: var(--radius-sm);
    margin-bottom: 16px; font-size: .9rem;
}
.flash-msg.info { background: #e3f2fd; color: #1565c0; }
.flash-msg.success { background: #e8f5e9; color: #2e7d32; }
.flash-msg.error { background: #fce4ec; color: #c62828; }

/* ---------- 相册 ---------- */
.album-grid {
    display: grid; grid-template-columns: repeat(auto-fill, minmax(240px, 1fr));
    gap: 20px;
}
.album-card {
    background: var(--white); border-radius: var(--radius);
    overflow: hidden; box-shadow: var(--shadow-sm); transition: var(--transition);
}
.album-card:hover { box-shadow: var(--shadow); transform: translateY(-2px); }
.album-cover {
    height: 200px; overflow: hidden; background: var(--gray-200);
    display: flex; align-items: center; justify-content: center;
}
.album-cover img { width: 100%; height: 100%; object-fit: cover; }
.album-info { padding: 16px; }
.album-info h3 { font-size: 1.05rem; margin-bottom: 6px; }
.album-info p { font-size: .84rem; color: var(--gray-500); }

.photo-grid {
    display: grid; grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
    gap: 12px;
}
.photo-item {
    position: relative; border-radius: var(--radius-sm); overflow: hidden;
    aspect-ratio: 1; background: var(--gray-200);
}
.photo-item img { width: 100%; height: 100%; object-fit: cover; }
.photo-delete {
    position: absolute; top: 8px; right: 8px;
    width: 28px; height: 28px; border-radius: 50%; border: none;
    background: rgba(0,0,0,.5); color: #fff; font-size: .9rem;
    display: none; align-items: center; justify-content: center;
}
.photo-item:hover .photo-delete { display: flex; }

/* ---------- 留言板 ---------- */
.message-box {
    background: var(--white); border-radius: var(--radius);
    padding: 22px; margin-bottom: 16px; box-shadow: var(--shadow-sm);
}
.message-header { display: flex; align-items: center; gap: 12px; margin-bottom: 12px; }
.message-avatar { width: 40px; height: 40px; border-radius: 50%; object-fit: cover; }
.message-user { font-weight: 600; font-size: .92rem; }
.message-time { font-size: .78rem; color: var(--gray-500); }
.message-content { color: var(--gray-700); font-size: .95rem; line-height: 1.8; }
.message-actions { margin-top: 10px; display: flex; gap: 14px; }
.message-actions button {
    background: none; border: none; font-size: .82rem; color: var(--gray-500);
    transition: var(--transition); padding: 0;
}
.message-actions button:hover { color: var(--primary); }

.message-reply { margin-left: 48px; margin-bottom: 16px; padding: 14px; background: var(--gray-100); border-radius: var(--radius-sm); }

/* ---------- 页脚 ---------- */
.footer {
    text-align: center; padding: 28px 20px;
    color: var(--gray-500); font-size: .82rem;
    border-top: 1px solid var(--gray-200); margin-top: 60px;
}

/* ---------- 响应式 ---------- */
@media (max-width: 768px) {
    .navbar { padding: 0 16px; }
    .nav-menu { display: none; position: absolute; top: 60px; left: 0; right: 0;
        flex-direction: column; background: var(--white);
        box-shadow: var(--shadow); padding: 8px 0;
    }
    .nav-menu.open { display: flex; }
    .hamburger { display: block; }
    .hero { height: 240px; }
    .hero-content h1 { font-size: 1.8rem; }
    .center-container { flex-direction: column; }
    .sidebar { width: 100%; display: flex; }
    .menu-list { display: flex; flex-wrap: wrap; gap: 4px; padding: 8px; }
    .menu-item a { border-left: none; border-bottom: 2px solid transparent; padding: 10px 16px; }
    .album-grid { grid-template-columns: repeat(auto-fill, minmax(160px, 1fr)); }
    .photo-grid { grid-template-columns: repeat(auto-fill, minmax(140px, 1fr)); }
    .message-reply { margin-left: 20px; }
}

/* ---------- 工具类 ---------- */
.text-center { text-align: center; }
.mt-2 { margin-top: 16px; }
.mb-2 { margin-bottom: 16px; }
.loading { text-align: center; padding: 40px; color: var(--gray-500); font-size: .94rem; }