/* ========================================
   CSS 变量系统 - 精致现代专业风格
   ======================================== */
:root {
    /* 主色调 - 深蓝灰色系 */
    --primary-dark: #0f172a;
    --primary: #1e293b;
    --primary-light: #334155;

    /* 强调色 - 锐利的珊瑚橙 */
    --accent: #f97316;
    --accent-hover: #ea580c;
    --accent-gradient: linear-gradient(135deg, #f97316 0%, #ea580c 100%);

    /* 中性色 */
    --bg-body: linear-gradient(135deg, #f8fafc 0%, #e2e8f0 100%);
    --bg-card: #ffffff;
    --bg-sidebar: linear-gradient(180deg, #f8fafc 0%, #f1f5f9 100%);
    --text-primary: #0f172a;
    --text-secondary: #64748b;
    --border-color: #e2e8f0;

    /* 阴影 - 更有层次感 */
    --shadow-sm: 0 1px 2px 0 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-accent: 0 4px 14px 0 rgba(249, 115, 22, 0.3);

    /* 过渡 */
    --transition-fast: 0.2s cubic-bezier(0.4, 0, 0.2, 1);
    --transition-normal: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    --transition-slow: 0.5s cubic-bezier(0.4, 0, 0.2, 1);

    /* 渐变背景 */
    --gradient-primary: linear-gradient(135deg, #0f172a 0%, #1e293b 50%, #334155 100%);
    --gradient-sidebar: linear-gradient(180deg, #f8fafc 0%, #f1f5f9 100%);
}

/* ========================================
   全局样式 & 字体
   ======================================== */
body {
    font-size: 0.9375rem;
    color: var(--text-primary);
    background: var(--bg-body);
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    line-height: 1.6;
    min-height: 100vh;
}

@import url('https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600;700&family=Playfair+Display:wght@600;700&display=swap');

/* ========================================
   导航栏
   ======================================== */
.navbar {
    background: var(--gradient-primary) !important;
    box-shadow: var(--shadow-lg);
    padding: 1rem 0;
    border-bottom: 3px solid var(--accent);
    backdrop-filter: blur(10px);
    position: relative;
    z-index: 1000;
}

.navbar-brand {
    font-family: 'Playfair Display', Georgia, serif;
    font-size: 1.5rem !important;
    font-weight: 700;
    letter-spacing: -0.02em;
    color: #ffffff !important;
    text-shadow: 0 2px 4px rgba(0, 0, 0, 0.3);
    background: var(--accent-gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.navbar .nav-link {
    color: rgba(255, 255, 255, 0.85) !important;
    font-weight: 500;
    transition: var(--transition-fast);
    position: relative;
    padding: 0.5rem 1rem;
}

.navbar .nav-link::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 50%;
    width: 0;
    height: 2px;
    background: var(--accent);
    transition: var(--transition-fast);
    transform: translateX(-50%);
}

.navbar .nav-link:hover {
    color: #ffffff !important;
    background: rgba(255, 255, 255, 0.1);
}

.navbar .nav-link:hover::after {
    width: 80%;
}

/* ========================================
   侧边栏
   ======================================== */
.sidebar {
    position: fixed;
    top: 80px;
    bottom: 0;
    left: 0;
    z-index: 100;
    padding: 0;
    background: var(--gradient-sidebar);
    box-shadow: var(--shadow-lg);
    border-right: 1px solid var(--border-color);
}

.sidebar-sticky {
    position: relative;
    top: 0;
    height: calc(100vh - 73px);
    padding: 1.5rem 0;
    overflow-x: hidden;
    overflow-y: auto;
}

.nav-link {
    font-weight: 500;
    color: var(--text-primary);
    padding: 0.875rem 1.5rem;
    margin: 0.375rem 0.75rem;
    border-radius: 12px;
    transition: var(--transition-normal);
    position: relative;
    overflow: hidden;
}

.nav-link::before {
    content: '';
    position: absolute;
    left: 0;
    top: 50%;
    transform: translateY(-50%);
    width: 4px;
    height: 0;
    background: var(--accent-gradient);
    border-radius: 0 3px 3px 0;
    transition: var(--transition-normal);
}

.nav-link:hover {
    background: rgba(249, 115, 22, 0.05);
    transform: translateX(6px);
    box-shadow: var(--shadow-sm);
}

.nav-link.active {
    color: var(--accent) !important;
    background: rgba(249, 115, 22, 0.1);
    font-weight: 600;
    box-shadow: var(--shadow-accent);
}

.nav-link.active::before {
    height: 60%;
}

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

.nav-link .bi {
    margin-right: 0.625rem;
    color: var(--text-secondary);
    transition: var(--transition-fast);
    font-size: 1.125rem;
}

/* ========================================
   主内容区
   ======================================== */
main {
    padding-top: 2rem;
    padding-left: 16.666667%; /* col-md-2 width */
}

@media (min-width: 992px) {
    main {
        padding-left: 16.666667%;
    }
}

@media (min-width: 768px) and (max-width: 991.98px) {
    main {
        padding-left: 25%; /* col-md-3 width */
    }
}

@media (max-width: 767.98px) {
    main {
        padding-left: 0;
    }
}

.border-bottom {
    border-bottom: 2px solid var(--border-color) !important;
    margin-bottom: 2rem;
}

.h2 {
    font-family: 'Playfair Display', Georgia, serif;
    font-weight: 700;
    color: var(--primary-dark);
}

/* ========================================
   卡片样式
   ======================================== */
.card {
    border: none;
    box-shadow: var(--shadow-lg);
    border-radius: 16px;
    overflow: hidden;
    transition: var(--transition-normal);
    background: var(--bg-card);
    position: relative;
}

.card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: var(--accent-gradient);
    opacity: 0;
    transition: var(--transition-normal);
}

.card:hover {
    box-shadow: var(--shadow-xl);
    transform: translateY(-4px);
}

.card:hover::before {
    opacity: 1;
}

.card-header {
    background: var(--gradient-sidebar);
    border-bottom: 2px solid var(--border-color);
    font-weight: 600;
    color: var(--primary);
    padding: 1.5rem;
    font-size: 1.1rem;
    position: relative;
}

.card-body {
    padding: 2rem;
}

.card-footer {
    background: var(--gradient-sidebar);
    border-top: 2px solid var(--border-color);
    padding: 1.5rem;
}

/* ========================================
   表单元素
   ======================================== */
.form-label {
    font-weight: 600;
    color: var(--primary);
    margin-bottom: 0.5rem;
    font-size: 0.9rem;
    letter-spacing: 0.02em;
}

.form-control {
    border: 2px solid var(--border-color);
    border-radius: 10px;
    padding: 0.875rem 1.25rem;
    font-size: 0.95rem;
    transition: var(--transition-normal);
    background: var(--bg-card);
}

.form-control:focus {
    border-color: var(--accent);
    box-shadow: 0 0 0 0.25rem rgba(249, 115, 22, 0.15);
    background: #ffffff;
    transform: translateY(-1px);
}

.form-select {
    border: 2px solid var(--border-color);
    border-radius: 10px;
    padding: 0.875rem 1.25rem;
    font-size: 0.95rem;
    transition: var(--transition-normal);
    background: var(--bg-card);
}

.form-select:focus {
    border-color: var(--accent);
    box-shadow: 0 0 0 0.25rem rgba(249, 115, 22, 0.15);
    background: #ffffff;
}

/* ========================================
   按钮系统
   ======================================== */
.btn {
    padding: 0.75rem 1.75rem;
    border-radius: 10px;
    font-weight: 600;
    letter-spacing: 0.03em;
    transition: var(--transition-normal);
    border: none;
    text-transform: uppercase;
    font-size: 0.875rem;
    position: relative;
    overflow: hidden;
}

.btn::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.2), transparent);
    transition: var(--transition-slow);
}

.btn:hover::before {
    left: 100%;
}

.btn-primary {
    background: var(--accent-gradient);
    box-shadow: var(--shadow-accent);
}

.btn-primary:hover {
    transform: translateY(-3px);
    box-shadow: 0 8px 20px rgba(249, 115, 22, 0.4);
}

.btn-secondary {
    background: var(--text-secondary);
    box-shadow: 0 4px 12px rgba(100, 116, 139, 0.3);
}

.btn-secondary:hover {
    background: var(--primary);
    transform: translateY(-3px);
    box-shadow: 0 6px 16px rgba(30, 41, 59, 0.4);
}

.btn-info {
    background: linear-gradient(135deg, #3b82f6 0%, #2563eb 100%);
    box-shadow: 0 4px 12px rgba(59, 130, 246, 0.3);
}

.btn-info:hover {
    background: linear-gradient(135deg, #2563eb 0%, #1d4ed8 100%);
    transform: translateY(-3px);
    box-shadow: 0 6px 16px rgba(59, 130, 246, 0.4);
}

.btn-sm {
    padding: 0.5rem 1.25rem;
    font-size: 0.8125rem;
}

/* ========================================
   Summernote 编辑器自定义
   ======================================== */
#summernote-editor {
    border-radius: 12px;
    overflow: hidden;
}

.note-editor.note-frame {
    border: 2px solid var(--border-color) !important;
    border-radius: 12px !important;
    box-shadow: var(--shadow-md);
}

.note-editor .note-toolbar {
    background: var(--gradient-sidebar) !important;
    border-bottom: 2px solid var(--border-color) !important;
    border-radius: 12px 12px 0 0;
}

.note-editor .note-editable {
    font-size: 1rem;
    line-height: 1.8;
    padding: 2rem;
    min-height: 500px;
    color: var(--text-primary);
}

/* ========================================
   列表组
   ======================================== */
.list-group-item {
    border: none;
    border-bottom: 1px solid var(--border-color);
    padding: 1.25rem 1.5rem;
    transition: var(--transition-normal);
    position: relative;
}

.list-group-item::before {
    content: '';
    position: absolute;
    left: 0;
    top: 0;
    bottom: 0;
    width: 0;
    background: var(--accent-gradient);
    transition: var(--transition-normal);
}

.list-group-item:hover {
    background: rgba(249, 115, 22, 0.03);
    padding-left: 2rem;
}

.list-group-item:hover::before {
    width: 4px;
}

.list-group-item:last-child {
    border-bottom: none;
}

.list-group-item a {
    font-weight: 500;
    color: var(--primary);
    text-decoration: none;
    transition: var(--transition-fast);
}

.list-group-item a:hover {
    color: var(--accent);
}

/* ========================================
   图片卡片网格
   ======================================== */
#image-list-container .card {
    height: 100%;
}

#image-list-container .card-img-top {
    border-radius: 16px 16px 0 0;
    height: 200px;
    object-fit: cover;
    transition: var(--transition-slow);
    filter: brightness(0.95);
}

#image-list-container .card:hover .card-img-top {
    transform: scale(1.08);
    filter: brightness(1);
}

#image-list-container .card-body {
    padding: 1.5rem;
}

#image-list-container .card-title {
    font-weight: 600;
    color: var(--primary);
    margin-bottom: 0.5rem;
    font-size: 1.05rem;
}

#image-list-container .card-text {
    font-size: 0.875rem;
    color: var(--text-secondary);
    word-break: break-word;
    margin-bottom: 1rem;
}

#image-list-container .card-footer {
    padding: 1.25rem;
    background: var(--gradient-sidebar);
    border-top: 1px solid var(--border-color);
}

/* ========================================
   模态框
   ======================================== */
.modal-content {
    border: none;
    border-radius: 16px;
    box-shadow: var(--shadow-xl);
    overflow: hidden;
}

.modal-header {
    background: var(--gradient-sidebar);
    border-bottom: 2px solid var(--border-color);
    padding: 1.75rem;
    position: relative;
}

.modal-header::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: var(--accent-gradient);
}

.modal-title {
    font-family: 'Playfair Display', Georgia, serif;
    font-weight: 700;
    color: var(--primary);
    font-size: 1.35rem;
}

.modal-body {
    padding: 2rem;
}

.modal-footer {
    background: var(--gradient-sidebar);
    border-top: 2px solid var(--border-color);
    padding: 1.75rem;
}

/* ========================================
   动画效果
   ======================================== */
@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes slideInLeft {
    from {
        opacity: 0;
        transform: translateX(-30px);
    }
    to {
        opacity: 1;
        transform: translateX(0);
    }
}

@keyframes slideInUp {
    from {
        opacity: 0;
        transform: translateY(40px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

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

.animate-fade-in {
    animation: fadeIn 0.6s cubic-bezier(0.4, 0, 0.2, 1) forwards;
}

.animate-slide-in-left {
    animation: slideInLeft 0.5s cubic-bezier(0.4, 0, 0.2, 1) forwards;
}

.animate-slide-in-up {
    animation: slideInUp 0.6s cubic-bezier(0.4, 0, 0.2, 1) forwards;
}

.animate-pulse {
    animation: pulse 2s cubic-bezier(0.4, 0, 0.6, 1) infinite;
}

.stagger-1 { animation-delay: 0.1s; opacity: 0; }
.stagger-2 { animation-delay: 0.2s; opacity: 0; }
.stagger-3 { animation-delay: 0.3s; opacity: 0; }
.stagger-4 { animation-delay: 0.4s; opacity: 0; }
.stagger-5 { animation-delay: 0.5s; opacity: 0; }
.stagger-6 { animation-delay: 0.6s; opacity: 0; }

/* ========================================
   响应式设计
   ======================================== */
@media (max-width: 767.98px) {
    .sidebar {
        position: relative;
        top: 0;
        bottom: auto;
        left: 0;
        right: 0;
        padding: 1rem 0;
        z-index: 1000;
        border-right: none;
        border-bottom: 2px solid var(--border-color);
    }

    .sidebar-sticky {
        height: auto;
        padding: 0;
        overflow: visible;
    }

    main {
        padding-top: 1.5rem;
    }

    .navbar-brand {
        font-size: 1.25rem !important;
    }

    .card {
        border-radius: 12px;
    }

    .card-body {
        padding: 1.5rem;
    }
}

/* ========================================
   登录页面特定样式
   ======================================== */
.login-container {
    min-height: 100vh;
    background:
        radial-gradient(circle at 20% 80%, rgba(249, 115, 22, 0.08) 0%, transparent 50%),
        radial-gradient(circle at 80% 20%, rgba(59, 130, 246, 0.08) 0%, transparent 50%),
        linear-gradient(135deg, #f8fafc 0%, #e2e8f0 100%);
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 2rem;
    position: relative;
    overflow: hidden;
}

.login-container::before {
    content: '';
    position: absolute;
    top: -50%;
    left: -50%;
    width: 200%;
    height: 200%;
    background:
        radial-gradient(circle, transparent 20%, rgba(255, 255, 255, 0.3) 21%, transparent 22%),
        radial-gradient(circle, transparent 20%, rgba(255, 255, 255, 0.3) 21%, transparent 22%);
    background-size: 60px 60px;
    opacity: 0.1;
    animation: patternMove 20s linear infinite;
}

@keyframes patternMove {
    0% {
        transform: translate(0, 0);
    }
    100% {
        transform: translate(60px, 60px);
    }
}

.login-card {
    background: var(--bg-card);
    border-radius: 24px;
    box-shadow: var(--shadow-xl);
    padding: 3.5rem;
    max-width: 420px;
    width: 100%;
    animation: fadeIn 0.8s cubic-bezier(0.4, 0, 0.2, 1);
    position: relative;
    z-index: 1;
}

.login-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 6px;
    background: var(--accent-gradient);
    border-radius: 24px 24px 0 0;
}

.login-title {
    font-family: 'Playfair Display', Georgia, serif;
    font-size: 2.25rem;
    font-weight: 700;
    background: var(--accent-gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    text-align: center;
    margin-bottom: 2.5rem;
    text-shadow: 0 2px 8px rgba(249, 115, 22, 0.1);
}

.login-card .form-control {
    padding: 0.875rem 1.25rem;
    font-size: 1rem;
    border-radius: 12px;
}

.login-card .btn {
    padding: 1rem 2.5rem;
    font-size: 1rem;
    margin-top: 2rem;
    width: 100%;
    border-radius: 12px;
}

/* ========================================
   工具类
   ======================================== */
.text-primary-custom {
    color: var(--primary) !important;
}

.bg-primary-custom {
    background: var(--primary) !important;
}

.border-primary-custom {
    border-color: var(--primary) !important;
}

/* ========================================
   额外的视觉效果
   ======================================== */
.glass-effect {
    background: rgba(255, 255, 255, 0.7);
    backdrop-filter: blur(10px);
    border: 1px solid rgba(255, 255, 255, 0.3);
}

.elevated {
    box-shadow: var(--shadow-xl);
    transform: translateY(-4px);
    transition: var(--transition-normal);
}

.elevated:hover {
    box-shadow: var(--shadow-xl);
    transform: translateY(-6px);
}

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

.shimmer {
    position: relative;
    overflow: hidden;
}

.shimmer::after {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.4), transparent);
    animation: shimmerEffect 2s infinite;
}

@keyframes shimmerEffect {
    0% {
        left: -100%;
    }
    100% {
        left: 100%;
    }
}

/* ========================================
   滚动条美化
   ======================================== */
::-webkit-scrollbar {
    width: 10px;
    height: 10px;
}

::-webkit-scrollbar-track {
    background: var(--bg-body);
}

::-webkit-scrollbar-thumb {
    background: var(--border-color);
    border-radius: 5px;
    transition: var(--transition-fast);
}

::-webkit-scrollbar-thumb:hover {
    background: var(--accent);
}