:root {
    --primary-color: #333333;
    --primary-hover: #000000;
    --secondary-color: #666666;
    --dark-color: #222222;
    --light-color: #f8f8f8;
    --gray-color: #888888;
    --border-color: #eeeeee;
    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.05);
    --shadow-md: 0 2px 4px rgba(0, 0, 0, 0.05);
    --shadow-lg: 0 4px 6px rgba(0, 0, 0, 0.05);
    --border-radius: 6px;
    --transition: all 0.3s ease;
    --error-color: #ff4d4d;
    --warning-color: #ffaa33;
    --success-color: #33cc99;
    --info-color: #3b82f6;
    --vip-color: #f59e0b;
    --tech-gradient: linear-gradient(135deg, #f8f8f8, #e9e9e9);
    --tech-accent: rgba(0, 0, 0, 0.03);
    --tech-glow: 0 0 15px rgba(0, 0, 0, 0.03);
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(10px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

body {
    font-family: 'Microsoft YaHei', 'PingFang SC', 'Helvetica Neue', Arial, sans-serif;
    background-color: white;
    color: var(--dark-color);
    line-height: 1.6;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    animation: fadeIn 0.5s ease-out;
}

.container {
    max-width: 1200px;
    width: 100%;
    margin: 0 auto;
    padding: 20px;
    flex: 1;
}


header {
    background: white;
    color: var(--dark-color);
    padding: 30px 20px;
    border-radius: var(--border-radius);
    margin-bottom: 30px;
    box-shadow: var(--shadow-sm);
    position: relative;
}

header h1 {
    text-align: center;
    margin-bottom: 20px;
    font-size: 1.8rem;
    font-weight: 600;
    position: relative;
    z-index: 1;
    letter-spacing: 0.5px;
}

header h1 i {
    margin-right: 10px;
    vertical-align: middle;
    color: var(--primary-color);
}

.search-container {
    max-width: 600px;
    margin: 0 auto;
    position: relative;
    z-index: 1;
}

.search-wrapper {
    display: flex;
    background-color: white;
    border-radius: var(--border-radius);
    box-shadow: var(--shadow-sm);
    border: 1px solid var(--border-color);
    padding: 4px;
    margin-bottom: 15px;
    transition: var(--transition);
}

.search-wrapper:focus-within {
    box-shadow: var(--shadow-md);
    border-color: #cccccc;
}

#searchInput {
    flex: 1;
    padding: 12px;
    border: none;
    font-size: 15px;
    border-radius: var(--border-radius) 0 0 var(--border-radius);
    transition: var(--transition);
    background-color: transparent;
}

#searchInput:focus {
    outline: none;
}

.button-group {
    display: flex;
}

button {
    padding: 10px 20px;
    border: none;
    border-radius: var(--border-radius);
    background-color: var(--dark-color);
    color: white;
    font-size: 15px;
    font-weight: 500;
    cursor: pointer;
    transition: var(--transition);
    position: relative;
    overflow: hidden;
}

button::after {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 0;
    height: 0;
    background-color: rgba(255, 255, 255, 0.2);
    border-radius: 50%;
    transform: translate(-50%, -50%);
    transition: width 0.5s, height 0.5s;
}

button:hover {
    background-color: var(--primary-hover);
}

button:hover::after {
    width: 300px;
    height: 300px;
    opacity: 0;
}

button:disabled {
    background-color: var(--gray-color);
    cursor: not-allowed;
    transform: none;
    box-shadow: none;
}

button i {
    margin-right: 8px;
    font-size: 1em;
    vertical-align: middle;
}

#searchArticleBtn {
    border-radius: 0 var(--border-radius) var(--border-radius) 0;
}


main {
    margin-bottom: 30px;
    position: relative;
}

.articles-container {
    background-color: white;
    padding: 30px;
    border-radius: var(--border-radius);
    box-shadow: var(--shadow-sm);
    transition: var(--transition);
}

.articles-container h2 {
    margin-bottom: 25px;
    color: var(--dark-color);
    font-size: 1.3rem;
    font-weight: 600;
    display: flex;
    align-items: center;
    position: relative;
}

.articles-container h2 i {
    margin-right: 8px;
    color: var(--primary-color);
}

.articles-list {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 25px;
    min-height: 400px;
}

.article-item {
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    padding: 20px;
    transition: transform 0.3s, box-shadow 0.3s, border-color 0.3s;
    cursor: pointer;
    display: flex;
    flex-direction: column;
    background-color: white;
    height: 100%;
    position: relative;
}

.article-item:hover {
    transform: translateY(-3px);
    box-shadow: var(--shadow-md);
    border-color: #cccccc;
}

.article-title {
    font-size: 16px;
    font-weight: 600;
    color: var(--dark-color);
    margin-bottom: 10px;
    line-height: 1.4;
}

.article-title i {
    margin-right: 6px;
    color: var(--secondary-color);
    font-size: 0.9em;
}

.article-summary {
    color: var(--gray-color);
    font-size: 14px;
    overflow: hidden;
    text-overflow: ellipsis;
    display: -webkit-box;
    -webkit-line-clamp: 3;
    -webkit-box-orient: vertical;
    flex-grow: 1;
    line-height: 1.6;
    margin-bottom: 12px;
}

.article-meta {
    display: flex;
    justify-content: space-between;
    font-size: 12px;
    color: #aaaaaa;
    padding-top: 10px;
    margin-top: auto;
    border-top: 1px solid var(--border-color);
}

.article-meta span {
    display: flex;
    align-items: center;
}

.article-meta i {
    margin-right: 4px;
    font-size: 14px;
    color: var(--gray-color);
}


.highlight {
    background-color: rgba(255, 230, 170, 0.3);
    padding: 0 2px;
}


.loading {
    display: flex;
    justify-content: center;
    align-items: center;
    flex-direction: column;
    height: 200px;
    width: 100%;
    color: var(--gray-color);
    font-size: 15px;
    grid-column: 1 / -1;
    position: relative;
}

.loading::before {
    content: "";
    width: 40px;
    height: 40px;
    margin-bottom: 20px;
    border-radius: 50%;
    border: 2px solid var(--border-color);
    border-top-color: var(--primary-color);
    animation: spin 1.2s linear infinite;
}

.loading::after {
    content: "正在加载安全资讯";
    display: block;
    position: relative;
    letter-spacing: 1px;
    animation: loadingText 1.5s infinite;
}

@keyframes spin {
    to {
        transform: rotate(360deg);
    }
}

@keyframes loadingText {
    0%, 100% {
        opacity: 0.5;
    }
    50% {
        opacity: 1;
    }
}

.error, .empty {
    text-align: center;
    padding: 50px 20px;
    color: var(--gray-color);
    grid-column: 1 / -1;
    display: flex;
    flex-direction: column;
    align-items: center;
    position: relative;
    border-radius: var(--border-radius);
    background-color: var(--light-color);
    animation: fadeIn 0.5s ease-out;
}

.error {
    color: var(--error-color);
}

.error i {
    font-size: 2.5rem;
    margin-bottom: 15px;
    color: var(--error-color);
    opacity: 0.8;
}

.empty {
    border: 1px dashed var(--border-color);
}

.empty i {
    font-size: 2.5rem;
    margin-bottom: 15px;
    color: var(--gray-color);
}


.pagination {
    display: flex;
    justify-content: center;
    align-items: center;
    margin-top: 30px;
    gap: 15px;
}

.pagination button {
    padding: 8px 16px;
    border-radius: var(--border-radius);
    font-size: 14px;
    background-color: white;
    color: var(--dark-color);
    border: 1px solid var(--border-color);
}

.pagination button:hover:not([disabled]) {
    background-color: var(--dark-color);
    color: white;
}

.pagination button:disabled {
    opacity: 0.5;
    cursor: not-allowed;
    background-color: #f8f8f8;
    color: #cccccc;
}

.pagination-info {
    font-size: 14px;
    color: var(--gray-color);
    padding: 8px 15px;
}


.notification {
    position: fixed;
    top: 20px;
    left: 50%;
    transform: translateX(-50%);
    padding: 12px 20px;
    border-radius: var(--border-radius);
    background-color: white;
    color: var(--dark-color);
    box-shadow: var(--shadow-md);
    z-index: 1000;
    max-width: 90%;
    min-width: 300px;
    text-align: center;
    opacity: 1;
    transition: opacity 0.3s;
    display: none;
    border-left: 3px solid var(--info-color);
}

.notification.info {
    border-left-color: var(--info-color);
}

.notification.success {
    border-left-color: var(--success-color);
}

.notification.warning {
    border-left-color: var(--warning-color);
}

.notification.error {
    border-left-color: var(--error-color);
}


footer {
    text-align: center;
    padding: 20px;
    color: var(--gray-color);
    margin-top: auto;
    font-size: 13px;
    border-top: 1px solid var(--border-color);
}


@media (max-width: 900px) {
    .articles-list {
        grid-template-columns: 1fr;
        gap: 15px;
    }
}

@media (max-width: 768px) {
    header {
        padding: 20px 15px;
    }
    
    header h1 {
        font-size: 1.5rem;
    }
    
    .articles-container {
        padding: 20px 15px;
    }
    
    .article-item {
        padding: 15px;
    }
}

@media (max-width: 480px) {
    .search-wrapper {
        flex-direction: column;
    }
    
    #searchInput {
        border-radius: var(--border-radius) var(--border-radius) 0 0;
    }
    
    #searchArticleBtn {
        border-radius: 0 0 var(--border-radius) var(--border-radius);
        margin-top: 5px;
    }
    
    .pagination {
        flex-wrap: wrap;
    }
    
    .notification {
        min-width: 90%;
    }
}


.auth-error-container {
    background-color: white;
    border-radius: var(--border-radius);
    box-shadow: var(--shadow-sm);
    border: 1px solid var(--border-color);
    padding: 30px 20px;
    text-align: center;
    max-width: 500px;
    margin: 0 auto;
}

.auth-error-box {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
}

.auth-error-icon {
    font-size: 3rem;
    margin-bottom: 20px;
    color: var(--error-color);
    width: 80px;
    height: 80px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 50%;
    background-color: var(--light-color);
}

.auth-error-icon .ri-login-box-line {
    color: var(--primary-color);
}

.auth-error-icon .ri-vip-crown-line {
    color: var(--vip-color);
}

.auth-error-box h2 {
    font-size: 1.5rem;
    margin-bottom: 15px;
    color: var(--dark-color);
}

.auth-error-box p {
    color: var(--gray-color);
    margin-bottom: 25px;
    font-size: 1rem;
    max-width: 90%;
}

.action-button {
    display: inline-block;
    padding: 10px 24px;
    border-radius: var(--border-radius);
    text-decoration: none;
    font-weight: 500;
    font-size: 0.95rem;
    transition: var(--transition);
}

.login-button {
    background-color: var(--primary-color);
    color: white;
}

.login-button:hover {
    background-color: var(--primary-hover);
    transform: translateY(-2px);
}

.vip-button {
    background-color: var(--vip-color);
    color: white;
}

.vip-button:hover {
    background-color: #e67e22;
    transform: translateY(-2px);
}