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

:root {
    --primary-color: #2c3e50;
    --secondary-color: #3498db;
    --accent-color: #e74c3c;
    --bg-color: #f8f9fa;
    --text-color: #333;
    --border-color: #ddd;
    --hover-color: #2980b9;
    --card-bg: #ffffff;
    --shadow: 0 2px 4px rgba(0,0,0,0.1);
    --shadow-hover: 0 4px 8px rgba(0,0,0,0.15);
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    line-height: 1.6;
    color: var(--text-color);
    background-color: var(--bg-color);
}

/* Header */
header {
    background-color: var(--primary-color);
    color: white;
    padding: 1rem 0;
    box-shadow: var(--shadow);
}

.header-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.site-title {
    font-size: 1.8rem;
    font-weight: 600;
}

.chinese-title {
    font-weight: 400;
    margin-left: 0.5rem;
}

.lang-switch {
    background-color: var(--secondary-color);
    color: white;
    border: none;
    padding: 0.5rem 1rem;
    border-radius: 4px;
    cursor: pointer;
    font-size: 0.9rem;
    transition: background-color 0.3s;
}

.lang-switch:hover {
    background-color: var(--hover-color);
}

/* Navigation */
.main-nav {
    background-color: rgba(0,0,0,0.1);
    padding: 0.5rem 0;
}

.main-nav ul {
    list-style: none;
    display: flex;
    justify-content: center;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 2rem;
    flex-wrap: wrap;
}

.main-nav li {
    margin: 0 1rem;
}

.main-nav a {
    color: white;
    text-decoration: none;
    padding: 0.5rem 1rem;
    display: block;
    transition: background-color 0.3s;
    border-radius: 4px;
}

.main-nav a:hover,
.main-nav a.active {
    background-color: rgba(255,255,255,0.2);
}

/* Container */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 2rem;
}

/* Hero Section */
.hero-section {
    text-align: center;
    padding: 3rem 0;
    background: linear-gradient(135deg, var(--secondary-color), var(--primary-color));
    color: white;
    border-radius: 8px;
    margin-bottom: 2rem;
}

.hero-section h2 {
    font-size: 2.5rem;
    margin-bottom: 1rem;
}

.hero-section p {
    font-size: 1.2rem;
    opacity: 0.9;
}

/* Filter Section */
.filter-section {
    margin-bottom: 2rem;
}

.filter-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
    justify-content: center;
}

.filter-btn {
    padding: 0.5rem 1.5rem;
    border: 2px solid var(--border-color);
    background-color: var(--card-bg);
    color: var(--text-color);
    border-radius: 20px;
    cursor: pointer;
    transition: all 0.3s;
    font-size: 0.95rem;
}

.filter-btn:hover {
    border-color: var(--secondary-color);
    color: var(--secondary-color);
}

.filter-btn.active {
    background-color: var(--secondary-color);
    color: white;
    border-color: var(--secondary-color);
}

/* Posts Grid */
.posts-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 2rem;
    margin-top: 2rem;
}

.post-card {
    background-color: var(--card-bg);
    border-radius: 8px;
    overflow: hidden;
    box-shadow: var(--shadow);
    transition: transform 0.3s, box-shadow 0.3s;
    cursor: pointer;
}

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

.post-card.locked {
    opacity: 0.6;
    position: relative;
}

.post-card.locked::after {
    content: '🔒';
    position: absolute;
    top: 10px;
    right: 10px;
    font-size: 1.5rem;
}

.post-image {
    width: 100%;
    height: 200px;
    object-fit: cover;
    background-color: var(--border-color);
}

.post-content {
    padding: 1.5rem;
}

.post-tag {
    display: inline-block;
    background-color: var(--secondary-color);
    color: white;
    padding: 0.25rem 0.75rem;
    border-radius: 12px;
    font-size: 0.8rem;
    margin-bottom: 0.5rem;
}

.post-title {
    font-size: 1.3rem;
    font-weight: 600;
    margin-bottom: 0.5rem;
    color: var(--primary-color);
}

.post-excerpt {
    color: #666;
    margin-bottom: 1rem;
    line-height: 1.5;
}

.post-meta {
    font-size: 0.85rem;
    color: #999;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.loading {
    grid-column: 1 / -1;
    text-align: center;
    padding: 3rem;
    color: #999;
}

/* Login Page */
.login-container {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(135deg, var(--secondary-color), var(--primary-color));
}

.login-box {
    background-color: var(--card-bg);
    padding: 3rem;
    border-radius: 8px;
    box-shadow: var(--shadow-hover);
    width: 100%;
    max-width: 450px;
    text-align: center;
}

.login-box h1 {
    margin-bottom: 1rem;
    color: var(--primary-color);
}

.login-box h2 {
    margin-bottom: 2rem;
    color: var(--text-color);
}

.form-group {
    margin-bottom: 1.5rem;
    text-align: left;
}

.form-group label {
    display: block;
    margin-bottom: 0.5rem;
    color: var(--text-color);
    font-weight: 500;
}

.form-group input,
.form-group select {
    width: 100%;
    padding: 0.75rem;
    border: 2px solid var(--border-color);
    border-radius: 4px;
    font-size: 1rem;
    transition: border-color 0.3s;
}

.form-group input:focus,
.form-group select:focus {
    outline: none;
    border-color: var(--secondary-color);
}

.btn {
    padding: 0.75rem 2rem;
    border: none;
    border-radius: 4px;
    font-size: 1rem;
    cursor: pointer;
    transition: background-color 0.3s;
}

.btn-primary {
    background-color: var(--secondary-color);
    color: white;
    width: 100%;
}

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

.btn-secondary {
    background-color: #95a5a6;
    color: white;
}

.btn-secondary:hover {
    background-color: #7f8c8d;
}

.error-message {
    background-color: #fee;
    color: var(--accent-color);
    padding: 1rem;
    border-radius: 4px;
    margin-top: 1rem;
    border: 1px solid var(--accent-color);
}

.success-message {
    background-color: #efe;
    color: #27ae60;
    padding: 1rem;
    border-radius: 4px;
    margin-top: 1rem;
    border: 1px solid #27ae60;
}

.form-toggle {
    margin-top: 1rem;
    text-align: center;
}

.form-toggle a {
    color: var(--secondary-color);
    text-decoration: none;
    font-size: 0.9rem;
}

.form-toggle a:hover {
    text-decoration: underline;
}

.login-footer {
    margin-top: 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.login-footer a {
    color: var(--secondary-color);
    text-decoration: none;
}

.login-footer a:hover {
    text-decoration: underline;
}

/* Admin Section */
.admin-section {
    background-color: var(--card-bg);
    padding: 2rem;
    border-radius: 8px;
    box-shadow: var(--shadow);
    margin-top: 2rem;
}

.entry-form {
    margin-top: 2rem;
}

.toolbar {
    display: flex;
    gap: 0.5rem;
    margin-bottom: 0.5rem;
    padding: 0.5rem;
    background-color: var(--bg-color);
    border-radius: 4px 4px 0 0;
    border: 2px solid var(--border-color);
    border-bottom: none;
}

.toolbar-btn {
    padding: 0.5rem 1rem;
    background-color: white;
    border: 1px solid var(--border-color);
    border-radius: 4px;
    cursor: pointer;
    font-size: 1rem;
    transition: background-color 0.3s;
}

.toolbar-btn:hover {
    background-color: var(--bg-color);
}

.content-editor {
    min-height: 300px;
    padding: 1rem;
    border: 2px solid var(--border-color);
    border-radius: 0 0 4px 4px;
    background-color: white;
    outline: none;
}

.content-editor:focus {
    border-color: var(--secondary-color);
}

.content-editor:empty::before {
    content: attr(data-placeholder-en);
    color: #999;
}

.content-editor[data-lang="zh"]:empty::before {
    content: attr(data-placeholder-zh);
}

.form-actions {
    display: flex;
    gap: 1rem;
    margin-top: 2rem;
}

.form-actions .btn {
    flex: 1;
}

/* Footer */
footer {
    background-color: var(--primary-color);
    color: white;
    text-align: center;
    padding: 2rem;
    margin-top: 4rem;
}

/* Responsive */
@media (max-width: 768px) {
    .header-container {
        flex-direction: column;
        gap: 1rem;
    }
    
    .main-nav ul {
        flex-direction: column;
        gap: 0.5rem;
    }
    
    .posts-grid {
        grid-template-columns: 1fr;
    }
    
    .hero-section h2 {
        font-size: 1.8rem;
    }
    
    .form-actions {
        flex-direction: column;
    }
}