/* General Body and Typography */
body {
    margin: 0;
    padding: 0;
    font-family: 'Noto Sans SC', 'Helvetica Neue', Helvetica, Arial, sans-serif;
    line-height: 1.6;
    color: #333;
    background-color: #f4f7f6;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    box-sizing: border-box;
}

*, *::before, *::after {
    box-sizing: inherit;
}

a {
    text-decoration: none;
    color: var(--primary-color, #007bff);
    transition: color 0.3s ease;
}

a:hover {
    color: var(--primary-color-dark, #0056b3);
}

h1, h2, h3, h4, h5, h6 {
    font-family: 'Noto Sans SC', sans-serif;
    margin-top: 0;
    margin-bottom: 0.5em;
    color: var(--dark-text, #343a40);
    line-height: 1.2;
}

p {
    margin-top: 0;
    margin-bottom: 1em;
}

/* Utility Classes */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
    width: 100%;
}

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

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

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

.clearfix::after {
    content: "";
    display: table;
    clear: both;
}

/* Buttons */
.btn {
    display: inline-block;
    font-weight: 400;
    color: #212529;
    text-align: center;
    vertical-align: middle;
    cursor: pointer;
    -webkit-user-select: none;
    -moz-user-select: none;
    -ms-user-select: none;
    user-select: none;
    background-color: transparent;
    border: 1px solid transparent;
    padding: 0.375rem 0.75rem;
    font-size: 1rem;
    line-height: 1.5;
    border-radius: 0.25rem;
    transition: color 0.15s ease-in-out, background-color 0.15s ease-in-out, border-color 0.15s ease-in-out, box-shadow 0.15s ease-in-out;
}

.btn-primary {
    color: #fff;
    background-color: var(--primary-color, #007bff);
    border-color: var(--primary-color, #007bff);
}

.btn-primary:hover {
    color: #fff;
    background-color: var(--primary-color-dark, #0056b3);
    border-color: var(--primary-color-dark, #0056b3);
}

.btn-secondary {
    color: #fff;
    background-color: var(--secondary-color, #6c757d);
    border-color: var(--secondary-color, #6c757d);
}

.btn-secondary:hover {
    color: #fff;
    background-color: var(--secondary-color-dark, #5a6268);
    border-color: var(--secondary-color-dark, #545b62);
}

.btn-outline-primary {
    color: var(--primary-color, #007bff);
    border-color: var(--primary-color, #007bff);
    background-color: transparent;
}
.btn-outline-primary:hover {
    color: #fff;
    background-color: var(--primary-color, #007bff);
    border-color: var(--primary-color, #007bff);
}

/* Forms */
.form-group {
    margin-bottom: 1rem;
}

.form-control {
    display: block;
    width: 100%;
    padding: 0.375rem 0.75rem;
    font-size: 1rem;
    line-height: 1.5;
    color: #495057;
    background-color: #fff;
    background-clip: padding-box;
    border: 1px solid var(--border-color, #ced4da);
    border-radius: 0.25rem;
    transition: border-color 0.15s ease-in-out, box-shadow 0.15s ease-in-out;
}

.form-control:focus {
    color: #495057;
    background-color: #fff;
    border-color: #80bdff;
    outline: 0;
    box-shadow: 0 0 0 0.2rem rgba(0, 123, 255, 0.25);
}

/* Responsive Images */
img {
    max-width: 100%;
    height: auto;
    display: block;
}

/* Cards */
.card {
    background-color: #fff;
    border: 1px solid var(--border-color, #e0e0e0);
    border-radius: 8px;
    box-shadow: 0 2px 5px rgba(0,0,0,0.05);
    margin-bottom: 20px;
    overflow: hidden;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.card:hover {
    transform: translateY(-3px);
    box-shadow: 0 4px 10px rgba(0,0,0,0.1);
}

.card-header {
    padding: 15px 20px;
    border-bottom: 1px solid var(--border-color, #e0e0e0);
    font-weight: bold;
    background-color: var(--light-bg, #f8f8f8);
    color: var(--dark-text, #343a40);
}

.card-body {
    padding: 20px;
}

/* Alerts */
.alert {
    padding: 1rem 1.25rem;
    margin-bottom: 1rem;
    border: 1px solid transparent;
    border-radius: 0.25rem;
    position: relative;
}

.alert-success {
    color: #155724;
    background-color: #d4edda;
    border-color: #c3e6cb;
}

.alert-danger {
    color: #721c24;
    background-color: #f8d7da;
    border-color: #f5c6cb;
}

.alert-info {
    color: #0c5460;
    background-color: #d1ecf1;
    border-color: #bee5eb;
}

/* Media Queries for general responsiveness */
@media (max-width: 768px) {
    body {
        font-size: 14px;
    }
    .container {
        padding: 0 15px;
    }
    .btn {
        padding: 0.3rem 0.6rem;
        font-size: 0.9rem;
    }
    h1 { font-size: 2.2em; }
    h2 { font-size: 1.8em; }
    h3 { font-size: 1.4em; }
}

@media (max-width: 480px) {
    h1 {
        font-size: 2em;
    }
    h2 {
        font-size: 1.5em;
    }
    .card-body { padding: 15px; }
}

/* Additional styles for potential shared components not in header/footer */
.section-title {
    font-size: 2.5em;
    text-align: center;
    margin-bottom: 40px;
    color: var(--dark-text, #343a40);
    position: relative;
    padding-bottom: 10px;
    font-weight: 700;
}
.section-title::after {
    content: '';
    position: absolute;
    left: 50%;
    bottom: 0;
    transform: translateX(-50%);
    width: 60px;
    height: 3px;
    background-color: var(--primary-color, #007bff);
    border-radius: 2px;
}

.grid-container {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 30px;
    margin-top: 30px;
    margin-bottom: 30px;
}

.feature-item {
    background-color: #fff;
    padding: 30px;
    border-radius: 8px;
    box-shadow: 0 4px 10px rgba(0,0,0,0.08);
    text-align: center;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}
.feature-item:hover {
    transform: translateY(-5px);
    box-shadow: 0 6px 15px rgba(0,0,0,0.12);
}
.feature-item i {
    font-size: 3.5em;
    color: var(--primary-color, #007bff);
    margin-bottom: 15px;
    display: block;
}
.feature-item h4 {
    font-size: 1.5em;
    margin-bottom: 10px;
    color: var(--dark-text, #343a40);
}
.feature-item p {
    color: #666;
    font-size: 0.95em;
}

.hero-section {
    background: linear-gradient(rgba(0,0,0,0.5), rgba(0,0,0,0.5)), url('https://via.placeholder.com/1500x500/007bff/ffffff?text=Hero+Background') no-repeat center center/cover;
    color: #fff;
    padding: 80px 20px;
    text-align: center;
    margin-bottom: 40px;
}

.hero-section h1 {
    font-size: 3.5em;
    margin-bottom: 20px;
    color: #fff;
    text-shadow: 2px 2px 4px rgba(0,0,0,0.3);
}

.hero-section p {
    font-size: 1.3em;
    margin-bottom: 30px;
    max-width: 800px;
    margin-left: auto;
    margin-right: auto;
}

.hero-section .btn {
    font-size: 1.1em;
    padding: 12px 25px;
    border-radius: 50px;
}

.hero-section .btn-primary {
    background-color: #fff;
    color: var(--primary-color, #007bff);
    border-color: #fff;
}

.hero-section .btn-primary:hover {
    background-color: var(--light-bg, #f0f0f0);
    border-color: var(--light-bg, #f0f0f0);
}

@media (max-width: 768px) {
    .hero-section h1 { font-size: 2.5em; }
    .hero-section p { font-size: 1.1em; }
    .hero-section { padding: 60px 15px; }
}

@media (max-width: 480px) {
    .hero-section h1 { font-size: 2em; }
    .hero-section p { font-size: 1em; }
    .hero-section .btn { padding: 10px 20px; font-size: 1em; }
}
/* 移动端内容区防溢出（系统追加，请勿删除） */
@media (max-width: 768px) {
  .page-content img {
    max-width: 100% !important;
    height: auto !important;
    display: block;
  }
  .page-content {
    overflow-x: hidden;
    max-width: 100%;
  }
  body {
    overflow-x: hidden;
  }
}