body {
    margin: 0;
    padding: 0;
    font-family: 'Microsoft YaHei', sans-serif;
    background: #332211;
    min-height: 100vh;
    padding: 20px;
}

.promotion-container {
    max-width: 800px;
    margin: 0 auto;
}

.promotion-item {
    background: #443322;
    border-radius: 10px;
    padding: 20px;
    margin-bottom: 20px;
    display: flex;
    align-items: center;
}

.platform-logo {
    width: 50px;
    height: 50px;
    margin-right: 20px;
    object-fit: contain;
}

.item-content {
    flex: 1;
}

.platform-name {
    color: white;
    font-size: 18px;
    font-weight: bold;
    margin-bottom: 5px;
}

.earnings {
    color: #ccc;
    font-size: 14px;
    margin-bottom: 10px;
}

.tag {
    display: inline-block;
    background: #f9c;
    color: #332211;
    padding: 3px 8px;
    border-radius: 4px;
    font-size: 12px;
    margin-right: 10px;
}

.promote-btn {
    background: #963;
    color: white;
    border: none;
    border-radius: 5px;
    padding: 8px 15px;
    cursor: pointer;
    transition: background 0.3s;
}

.promote-btn:hover {
    background: #b84;
}

.task-details {
    background: #443322;
    border-radius: 10px;
    padding: 20px;
    margin-bottom: 20px;
    color: white;
}

.detail-section {
    margin-bottom: 15px;
}

.detail-section h4 {
    color: #f9a825;
    margin-bottom: 10px;
}

.start-promotion-btn {
    background: #f9a825;
    color: white;
    border: none;
    border-radius: 25px;
    padding: 12px 30px;
    font-size: 16px;
    cursor: pointer;
    display: block;
    width: 200px;
    margin: 20px auto 0;
    transition: background 0.3s;
}

.start-promotion-btn:hover {
    background: #ffb74d;
}

body::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.3);
    z-index: -1;
}

.login-container {
    background: rgba(255, 255, 255, 0.9);
    padding: 2rem 3rem;
    border-radius: 10px;
    box-shadow: 0 15px 35px rgba(0, 0, 0, 0.2);
    width: 350px;
    text-align: center;
}

h1 {
    color: #333;
    margin-bottom: 1.5rem;
}

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

label {
    display: block;
    margin-bottom: 0.5rem;
    color: #555;
}

input {
    width: 100%;
    padding: 0.8rem;
    border: 1px solid #ddd;
    border-radius: 5px;
    font-size: 1rem;
}

button {
    width: 100%;
    padding: 0.8rem;
    background: #667eea;
    color: white;
    border: none;
    border-radius: 5px;
    font-size: 1rem;
    cursor: pointer;
    transition: background 0.3s;
}

button:hover {
    background: #5a6fd1;
}

.bottom-nav {
    position: fixed;
    bottom: 0;
    left: 0;
    right: 0;
    display: flex;
    background: #332211;
    padding: 10px 0;
}

.nav-item {
    flex: 1;
    text-align: center;
    color: white;
    font-size: 16px;
    cursor: pointer;
}

.nav-item:hover {
    color: #f9c;
}

.profile-container {
    display: none;
    padding: 20px;
}

.profile-card {
    background: #443322;
    border-radius: 10px;
    padding: 20px;
    margin: 20px auto;
    max-width: 500px;
    text-align: center;
}

.profile-avatar {
    width: 100px;
    height: 100px;
    border-radius: 50%;
    object-fit: cover;
    margin-bottom: 15px;
}

.profile-name, .profile-level, .profile-points {
    color: white;
    margin-bottom: 10px;
}