/* 全局样式 */
* {
    box-sizing: border-box;
}

html {
    font-size: 16px;
}

@media (max-width: 768px) {
    html {
        font-size: 14px;
    }
}

@media (max-width: 480px) {
    html {
        font-size: 12px;
    }
}

body {
    background-color: #f8f9fa;
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    margin: 0;
    padding: 0;
    line-height: 1.6;
}

/* 容器样式 */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 15px;
}

@media (max-width: 768px) {
    .container {
        padding: 10px;
    }
}

/* 笔记内容区域样式 */
.note-content {
    background-color: white;
    padding: 25px;
    border-radius: 8px;
    box-shadow: 0 0 10px rgba(0,0,0,0.05);
    line-height: 1.8;
    font-size: 1rem;
    margin-bottom: 20px;
}

@media (max-width: 768px) {
    .note-content {
        padding: 20px;
        font-size: 0.9rem;
    }
}

@media (max-width: 480px) {
    .note-content {
        padding: 15px;
        font-size: 0.85rem;
    }
}

/* 卡片样式优化 */
.card {
    box-shadow: 0 2px 10px rgba(0,0,0,0.05);
    border: 1px solid rgba(0,0,0,0.05);
    border-radius: 8px;
    overflow: hidden;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.card:hover {
    transform: translateY(-5px);
    box-shadow: 0 6px 20px rgba(0,0,0,0.1);
}

/* 按钮样式 */
.btn {
    border-radius: 5px;
    padding: 10px 20px;
    font-weight: 500;
    text-decoration: none;
    display: inline-block;
    border: none;
    cursor: pointer;
    transition: all 0.3s ease;
    text-align: center;
    font-size: 1rem;
}

@media (max-width: 768px) {
    .btn {
        padding: 8px 16px;
        font-size: 0.9rem;
    }
}

/* 导航栏样式 */
.navbar {
    background-color: #1a73e8; /* 更深的蓝色 */
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
    padding: 15px 0;
}

.navbar-brand {
    font-weight: bold;
    font-size: 1.5rem;
    text-decoration: none;
    color: #ffffff; /* 白色文字，提高对比度 */
    display: flex;
    align-items: center;
}

.navbar-brand:hover {
    color: #e0f0ff; /* 悬停时的颜色 */
}

@media (max-width: 768px) {
    .navbar-brand {
        font-size: 1.3rem;
    }
}

.navbar-nav {
    display: flex;
    flex-direction: row;
    gap: 20px;
}

.nav-link {
    color: #e8f0fe; /* 浅蓝色文字 */
    text-decoration: none;
    padding: 5px 10px;
    border-radius: 4px;
    transition: color 0.3s ease;
    font-weight: 500;
}

.nav-link:hover {
    color: #ffffff; /* 悬停时变为白色 */
    background-color: rgba(255, 255, 255, 0.1);
}

/* 响应式菜单按钮样式 */
.navbar-toggle {
    display: none;
    flex-direction: column;
    justify-content: space-between;
    width: 30px;
    height: 21px;
}

.navbar-toggle span {
    display: block;
    height: 3px;
    width: 100%;
    background-color: #e8f0fe; /* 浅蓝色线条 */
    border-radius: 3px;
    transition: all 0.3s ease;
}

@media (max-width: 768px) {
    .navbar-toggle {
        display: flex;
    }
    
    .navbar-nav {
        display: none;
        flex-direction: column;
        margin-top: 10px;
        background-color: #1a73e8;
        padding: 15px 0;
        border-radius: 8px;
    }
    
    .navbar-nav.show {
        display: flex;
    }
}

/* 页面标题 */
h1 {
    color: #2c3e50;
    margin-bottom: 20px;
    padding-bottom: 10px;
    border-bottom: 2px solid #3498db;
    font-size: 2rem;
}

@media (max-width: 768px) {
    h1 {
        font-size: 1.6rem;
        margin-bottom: 15px;
    }
}

@media (max-width: 480px) {
    h1 {
        font-size: 1.4rem;
        margin-bottom: 12px;
    }
}

h2 {
    color: #34495e;
    margin-top: 25px;
    margin-bottom: 15px;
    font-size: 1.6rem;
}

@media (max-width: 768px) {
    h2 {
        font-size: 1.4rem;
        margin-top: 20px;
        margin-bottom: 12px;
    }
}

/* 表格样式 */
.table {
    width: 100%;
    max-width: 100%;
    overflow-x: auto;
    display: block;
}

.table th,
.table td {
    padding: 12px 15px;
    text-align: left;
    border-bottom: 1px solid #eee;
}

.table th {
    border-top: none;
    font-weight: 600;
    background-color: #f8f9fa;
}

@media (max-width: 768px) {
    .table th,
    .table td {
        padding: 8px 10px;
        font-size: 0.9rem;
    }
}

/* 表单样式 */
.form-group {
    margin-bottom: 20px;
}

.form-control {
    width: 100%;
    padding: 10px 15px;
    border: 1px solid #ddd;
    border-radius: 5px;
    font-size: 1rem;
    transition: border-color 0.3s ease;
}

.form-control:focus {
    outline: none;
    border-color: #3498db;
    box-shadow: 0 0 0 2px rgba(52, 152, 219, 0.2);
}

@media (max-width: 768px) {
    .form-control {
        padding: 8px 12px;
        font-size: 0.9rem;
    }
}

/* 响应式网格布局 */
.row {
    display: flex;
    flex-wrap: wrap;
    margin: 0 -10px;
}

.col-md-6 {
    flex: 0 0 50%;
    max-width: 50%;
    padding: 0 10px;
}

.col-lg-4 {
    flex: 0 0 33.3333%;
    max-width: 33.3333%;
    padding: 0 10px;
}

.col-sm-12 {
    flex: 0 0 100%;
    max-width: 100%;
    padding: 0 10px;
}

@media (max-width: 992px) {
    .col-lg-4 {
        flex: 0 0 50%;
        max-width: 50%;
    }
}

@media (max-width: 768px) {
    .row {
        flex-direction: column;
    }
    
    .col-md-6, 
    .col-lg-4 {
        flex: 0 0 100%;
        max-width: 100%;
        padding: 0;
    }
    
    .btn {
        display: block;
        width: 100%;
        margin-bottom: 10px;
    }
}

/* 文本对齐 */
.text-center {
    text-align: center;
}

.text-left {
    text-align: left;
}

.text-right {
    text-align: right;
}

@media (max-width: 768px) {
    .text-center-md {
        text-align: center;
    }
}

/* 工具类 */
.mt-1 { margin-top: 0.25rem; }
.mt-2 { margin-top: 0.5rem; }
.mt-3 { margin-top: 1rem; }
.mt-4 { margin-top: 1.5rem; }
.mt-5 { margin-top: 3rem; }

.mb-1 { margin-bottom: 0.25rem; }
.mb-2 { margin-bottom: 0.5rem; }
.mb-3 { margin-bottom: 1rem; }
.mb-4 { margin-bottom: 1.5rem; }
.mb-5 { margin-bottom: 3rem; }

.p-1 { padding: 0.25rem; }
.p-2 { padding: 0.5rem; }
.p-3 { padding: 1rem; }
.p-4 { padding: 1.5rem; }
.p-5 { padding: 3rem; }

.d-none { display: none; }
.d-block { display: block; }
.d-inline { display: inline; }
.d-flex { display: flex; }

.justify-content-center { justify-content: center; }
.justify-content-between { justify-content: space-between; }
.align-items-center { align-items: center; }

/* 响应式图片 */
img {
    max-width: 100%;
    height: auto;
}

/* 通用间距 */
.page-header {
    margin-bottom: 2rem;
    padding-bottom: 1rem;
    border-bottom: 1px solid #eee;
}

/* 移动端优先的汉堡菜单 */
.navbar-toggle {
    display: none;
    flex-direction: column;
    cursor: pointer;
    padding: 5px;
}

@media (max-width: 768px) {
    .navbar-toggle {
        display: flex;
    }
    
    .navbar-nav {
        display: none;
        flex-direction: column;
        margin-top: 10px;
    }
    
    .navbar-nav.show {
        display: flex;
    }
}

/* 动画过渡效果 */
.fade-in {
    animation: fadeIn 0.5s ease-in;
}

@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

/* 滚动条样式优化 */
::-webkit-scrollbar {
    width: 8px;
    height: 8px;
}

::-webkit-scrollbar-track {
    background: #f1f1f1;
}

::-webkit-scrollbar-thumb {
    background: #c1c1c1;
    border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
    background: #a0a0a0;
}