/**
 * 星络图书服务系统 - 全局主题样式
 * 设计风格：出版/新闻 - 权威可信
 * 主色: #1E3A8A  辅色: #DC2626  背景: #F8FAFC
 */

/* ========== CSS 变量 ========== */
:root {
    --primary:       #1E3A8A;
    --primary-light: #3B82F6;
    --primary-dark:  #1E2F6A;
    --primary-bg:    #EFF6FF;
    --secondary:     #DC2626;
    --secondary-light:#EF4444;
    --secondary-bg:  #FEF2F2;
    --bg:            #F8FAFC;
    --bg-card:       #FFFFFF;
    --text:          #1E293B;
    --text-secondary:#6B7280;
    --text-light:    #9CA3AF;
    --border:        #E2E8F0;
    --shadow-sm:     0 1px 2px rgba(0,0,0,0.05);
    --shadow:        0 4px 12px rgba(0,0,0,0.08);
    --shadow-lg:     0 12px 40px rgba(0,0,0,0.12);
    --shadow-glow:   0 0 20px rgba(30,58,138,0.15);
    --radius:        12px;
    --radius-sm:     8px;
    --radius-lg:     16px;
    --transition:    all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

/* ========== 全局基础 ========== */
body {
    background: var(--bg);
    color: var(--text);
    font-family: 'PingFang SC', 'Microsoft YaHei', 'Noto Sans SC', sans-serif;
    -webkit-font-smoothing: antialiased;
}

a { color: var(--primary-light); transition: var(--transition); }
a:hover { color: var(--primary); }

/* ========== 按钮系统 ========== */
.btn {
    border-radius: var(--radius-sm);
    font-weight: 500;
    transition: var(--transition);
    position: relative;
    overflow: hidden;
}
.btn::after {
    content: '';
    position: absolute;
    inset: 0;
    background: rgba(255,255,255,0);
    transition: background 0.3s;
}
.btn:hover::after { background: rgba(255,255,255,0.08); }
.btn:active { transform: scale(0.97); }

.btn-primary {
    background: linear-gradient(135deg, var(--primary) 0%, var(--primary-light) 100%);
    border: none;
    box-shadow: 0 2px 8px rgba(30,58,138,0.3);
}
.btn-primary:hover {
    box-shadow: 0 4px 16px rgba(30,58,138,0.4);
    transform: translateY(-1px);
}

.btn-danger {
    background: linear-gradient(135deg, var(--secondary) 0%, var(--secondary-light) 100%);
    border: none;
    box-shadow: 0 2px 8px rgba(220,38,38,0.3);
}
.btn-danger:hover {
    box-shadow: 0 4px 16px rgba(220,38,38,0.4);
    transform: translateY(-1px);
}

.btn-outline-primary {
    border-color: var(--primary-light);
    color: var(--primary);
}
.btn-outline-primary:hover {
    background: var(--primary);
    border-color: var(--primary);
    transform: translateY(-1px);
}

.btn-sm { border-radius: 6px; }

/* ========== 卡片 ========== */
.card {
    border: 1px solid var(--border);
    border-radius: var(--radius);
    background: var(--bg-card);
    box-shadow: var(--shadow-sm);
    transition: var(--transition);
    overflow: hidden;
}
.card:hover {
    box-shadow: var(--shadow-lg);
    transform: translateY(-4px);
    border-color: var(--primary-light);
}
.card-header {
    background: linear-gradient(135deg, var(--primary) 0%, var(--primary-light) 100%);
    color: #fff;
    border-bottom: none;
    font-weight: 600;
    padding: 14px 20px;
}
.card-header.bg-dark {
    background: linear-gradient(135deg, #1E293B 0%, #334155 100%) !important;
}
.card-header.bg-warning {
    background: linear-gradient(135deg, #D97706 0%, #F59E0B 100%) !important;
}
.card-header.bg-info {
    background: linear-gradient(135deg, #0E7490 0%, #06B6D4 100%) !important;
}
.card-header.bg-success {
    background: linear-gradient(135deg, #047857 0%, #10B981 100%) !important;
}
.card-header.bg-danger {
    background: linear-gradient(135deg, #B91C1C 0%, #EF4444 100%) !important;
}

/* ========== 导航栏 ========== */
.navbar {
    background: rgba(255,255,255,0.92) !important;
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border-bottom: 2px solid transparent;
    border-image: linear-gradient(90deg, var(--primary) 0%, var(--secondary) 100%) 1;
    box-shadow: var(--shadow-sm);
    transition: var(--transition);
}
.navbar-brand {
    font-weight: 800 !important;
    font-size: 1.25rem;
    background: linear-gradient(135deg, var(--primary) 0%, var(--primary-light) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}
.nav-link {
    font-weight: 500;
    color: var(--text) !important;
    position: relative;
    padding: 8px 14px !important;
    border-radius: 6px;
    transition: var(--transition);
}
.nav-link:hover {
    color: var(--primary) !important;
    background: var(--primary-bg);
}
.nav-link.active::after {
    content: '';
    position: absolute;
    bottom: 2px; left: 50%; transform: translateX(-50%);
    width: 20px; height: 3px;
    background: var(--primary);
    border-radius: 2px;
}

/* ========== 侧边栏（后台） ========== */
.sidebar {
    position: fixed;
    top: 0;
    left: 0;
    width: 240px;
    min-height: 100vh;
    z-index: 100;
    background: linear-gradient(180deg, #0F172A 0%, #1E293B 60%, #1E3A8A 100%) !important;
    box-shadow: 4px 0 24px rgba(0,0,0,0.15);
}

/* 侧边栏滚动 */
.sidebar nav {
    overflow-y: auto;
    max-height: calc(100vh - 60px);
}

/* 主内容区偏移 */
.main-content {
    margin-left: 240px;
    padding: 24px;
    min-height: 100vh;
}
.sidebar .nav-link {
    color: rgba(255,255,255,0.7) !important;
    border-radius: 8px;
    margin: 2px 8px;
    padding: 10px 16px !important;
    transition: var(--transition);
}
.sidebar .nav-link:hover {
    color: #fff !important;
    background: rgba(255,255,255,0.1);
    padding-left: 22px !important;
}
.sidebar .nav-link.active {
    color: #fff !important;
    background: linear-gradient(135deg, rgba(59,130,246,0.4) 0%, rgba(30,58,138,0.4) 100%);
    border-left: 3px solid var(--primary-light);
    padding-left: 13px !important;
}

/* ========== 表单 ========== */
.form-control, .form-select {
    border: 1.5px solid var(--border);
    border-radius: var(--radius-sm);
    padding: 10px 14px;
    transition: var(--transition);
    background: #fff;
}
.form-control:focus, .form-select:focus {
    border-color: var(--primary-light);
    box-shadow: 0 0 0 3px rgba(59,130,246,0.15);
    outline: none;
}
.form-label {
    font-weight: 600;
    color: var(--text);
    margin-bottom: 6px;
    font-size: 0.9rem;
}

/* ========== 表格 ========== */
.table {
    border-radius: var(--radius);
    overflow: hidden;
}
.table thead th {
    background: var(--primary-bg);
    color: var(--primary-dark);
    font-weight: 700;
    border-bottom: 2px solid var(--border);
    padding: 12px 16px;
    font-size: 0.85rem;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}
.table tbody tr {
    transition: var(--transition);
}
.table tbody tr:hover {
    background: var(--primary-bg);
}

/* ========== 徽章 ========== */
.badge {
    font-weight: 600;
    border-radius: 6px;
    padding: 4px 10px;
    font-size: 0.75rem;
}
.badge.bg-success { background: #059669 !important; }
.badge.bg-secondary { background: #6B7280 !important; }
.badge.bg-warning { background: #D97706 !important; color: #fff !important; }
.badge.bg-danger { background: var(--secondary) !important; }
.badge.bg-primary { background: var(--primary) !important; }

/* ========== 提示框 ========== */
.alert {
    border: none;
    border-radius: var(--radius);
    border-left: 4px solid transparent;
    padding: 14px 20px;
    font-weight: 500;
}
.alert-success { background: #ECFDF5; color: #047857; border-left-color: #10B981; }
.alert-danger  { background: #FEF2F2; color: #B91C1C; border-left-color: #EF4444; }
.alert-warning { background: #FFFBEB; color: #B45309; border-left-color: #F59E0B; }
.alert-info    { background: #EFF6FF; color: #1E40AF; border-left-color: #3B82F6; }

/* ========== 公告栏 ========== */
.announcement-bar {
    background: linear-gradient(90deg, var(--secondary) 0%, #B91C1C 50%, var(--secondary) 100%);
    background-size: 200% 100%;
    box-shadow: 0 2px 12px rgba(220,38,38,0.3);
}

/* ========== 图书卡片（前台首页） ========== */
.book-card {
    border-radius: var(--radius-lg) !important;
    border: 1px solid var(--border) !important;
}
.book-card:hover {
    transform: translateY(-8px) scale(1.01) !important;
    box-shadow: var(--shadow-glow) !important;
    border-color: var(--primary-light) !important;
}
.book-cover {
    border-radius: var(--radius-lg) var(--radius-lg) 0 0 !important;
}
.book-title {
    color: var(--primary-dark) !important;
    transition: var(--transition);
}
.book-card:hover .book-title {
    color: var(--primary) !important;
}

/* ========== 购买按钮 ========== */
.btn-buy {
    background: linear-gradient(135deg, var(--secondary) 0%, var(--secondary-light) 100%) !important;
    border: none !important;
    border-radius: var(--radius-sm) !important;
    font-weight: 700 !important;
    letter-spacing: 0.5px;
    box-shadow: 0 2px 8px rgba(220,38,38,0.3);
    transition: var(--transition);
}
.btn-buy:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(220,38,38,0.4);
}

/* ========== Section 标题 ========== */
.section-title {
    border-left: 4px solid var(--primary) !important;
    color: var(--primary-dark) !important;
    position: relative;
    padding-bottom: 8px;
}
.section-title::after {
    content: '';
    position: absolute;
    bottom: 0; left: 12px;
    width: 40px; height: 3px;
    background: linear-gradient(90deg, var(--secondary) 0%, transparent 100%);
    border-radius: 2px;
}

/* ========== 页脚 ========== */
footer {
    background: linear-gradient(135deg, #0F172A 0%, #1E293B 100%);
    border-top: 3px solid var(--primary);
}

/* ========== 微交互：页面入场 ========== */
@keyframes fadeInUp {
    from { opacity: 0; transform: translateY(20px); }
    to   { opacity: 1; transform: translateY(0); }
}
@keyframes fadeIn {
    from { opacity: 0; }
    to   { opacity: 1; }
}
.animate-in {
    animation: fadeInUp 0.5s ease-out both;
}
.animate-in:nth-child(2) { animation-delay: 0.1s; }
.animate-in:nth-child(3) { animation-delay: 0.2s; }
.animate-in:nth-child(4) { animation-delay: 0.3s; }

/* ========== 微交互：加载动画 ========== */
@keyframes spin { to { transform: rotate(360deg); } }
@keyframes pulse { 0%,100% { opacity:1; } 50% { opacity:0.5; } }

.loading-spinner {
    width: 20px; height: 20px;
    border: 2px solid rgba(255,255,255,0.3);
    border-top-color: #fff;
    border-radius: 50%;
    animation: spin 0.6s linear infinite;
    display: inline-block;
}

/* ========== 微交互：Toast 通知 ========== */
.toast-container {
    position: fixed;
    top: 20px; right: 20px;
    z-index: 9999;
}
.toast-msg {
    background: var(--bg-card);
    border-radius: var(--radius);
    box-shadow: var(--shadow-lg);
    padding: 14px 20px;
    margin-bottom: 10px;
    border-left: 4px solid var(--primary);
    animation: fadeInUp 0.3s ease-out;
    display: flex; align-items: center; gap: 10px;
    min-width: 280px;
}

/* ========== 微交互：图片悬停放大 ========== */
.img-hover-zoom {
    overflow: hidden;
}
.img-hover-zoom img {
    transition: transform 0.5s cubic-bezier(0.4, 0, 0.2, 1);
}
.img-hover-zoom:hover img {
    transform: scale(1.08);
}

/* ========== 微交互：输入框聚焦标签动画 ========== */
.form-floating > label {
    transition: var(--transition);
}

/* ========== 微交互：下拉菜单 ========== */
.dropdown-menu {
    border: 1px solid var(--border);
    border-radius: var(--radius);
    box-shadow: var(--shadow-lg);
    padding: 6px;
    animation: fadeIn 0.2s ease-out;
}
.dropdown-item {
    border-radius: 6px;
    padding: 8px 14px;
    transition: var(--transition);
    font-weight: 500;
}
.dropdown-item:hover {
    background: var(--primary-bg);
    color: var(--primary);
}

/* ========== 分页 ========== */
.pagination .page-link {
    border-radius: 8px !important;
    margin: 0 3px;
    border-color: var(--border);
    color: var(--primary);
    transition: var(--transition);
    font-weight: 500;
}
.pagination .page-item.active .page-link {
    background: linear-gradient(135deg, var(--primary) 0%, var(--primary-light) 100%);
    border-color: var(--primary);
    box-shadow: 0 2px 8px rgba(30,58,138,0.3);
}

/* ========== 滚动条美化 ========== */
::-webkit-scrollbar { width: 6px; height: 6px; }
::-webkit-scrollbar-track { background: var(--bg); }
::-webkit-scrollbar-thumb { background: var(--text-light); border-radius: 3px; }
::-webkit-scrollbar-thumb:hover { background: var(--text-secondary); }

/* ========== 响应式微调 ========== */
@media (max-width: 768px) {
    .card:hover { transform: none; }
    .book-card:hover { transform: translateY(-4px) !important; }
    .sidebar { width: 100% !important; min-height: auto !important; position: relative !important; }
    .main-content { margin-left: 0 !important; padding: 16px !important; }
}