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

body {
    font-family: 'Microsoft YaHei', 'PingFang SC', sans-serif;
    height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
    background: linear-gradient(135deg, #0f0c29 0%, #302b63 50%, #24243e 100%);
    overflow: hidden;
}

/* 背景光效 */
.bg-circle {
    position: absolute;
    border-radius: 50%;
    filter: blur(80px);
    opacity: 0.3;
}

.bg-circle-1 {
    width: 400px;
    height: 400px;
    background: #4a6cf7;
    top: -100px;
    right: -100px;
}

.bg-circle-2 {
    width: 350px;
    height: 350px;
    background: #f74a93;
    bottom: -80px;
    left: -80px;
}

/* 登录卡片 */
.login-box {
    position: relative;
    z-index: 10;
    width: 400px;
    background: rgba(255, 255, 255, 0.05);
    backdrop-filter: blur(20px);
    border-radius: 20px;
    padding: 45px 35px;
    box-shadow: 0 20px 50px rgba(0, 0, 0, 0.5);
    border: 1px solid rgba(255, 255, 255, 0.1);
}

.login-box h2 {
    color: #fff;
    text-align: center;
    font-size: 26px;
    margin-bottom: 8px;
    letter-spacing: 2px;
}

.login-box .subtitle {
    color: rgba(255, 255, 255, 0.5);
    text-align: center;
    font-size: 13px;
    margin-bottom: 35px;
}

.input-group {
    position: relative;
    margin-bottom: 25px;
}

.input-group .icon {
    position: absolute;
    left: 15px;
    top: 50%;
    transform: translateY(-50%);
    color: rgba(255, 255, 255, 0.4);
    font-size: 18px;
}

.input-group input {
    width: 100%;
    padding: 14px 15px 14px 45px;
    background: rgba(255, 255, 255, 0.08);
    border: 1px solid rgba(255, 255, 255, 0.15);
    border-radius: 10px;
    color: #fff;
    font-size: 15px;
    outline: none;
    transition: all 0.3s;
}

.input-group input:focus {
    border-color: #4a6cf7;
    background: rgba(255, 255, 255, 0.12);
    box-shadow: 0 0 15px rgba(74, 108, 247, 0.2);
}

.input-group input::placeholder {
    color: rgba(255, 255, 255, 0.3);
}

.login-btn {
    width: 100%;
    padding: 14px;
    background: linear-gradient(135deg, #4a6cf7 0%, #6a3ef7 100%);
    border: none;
    border-radius: 10px;
    color: #fff;
    font-size: 16px;
    font-weight: bold;
    cursor: pointer;
    letter-spacing: 2px;
    transition: all 0.3s;
    margin-top: 10px;
}

.login-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 10px 30px rgba(74, 108, 247, 0.4);
}

.login-btn:active {
    transform: translateY(0);
}

.error-msg {
    color: #ff6b6b;
    text-align: center;
    font-size: 13px;
    margin-top: 15px;
    min-height: 20px;
}

.loading {
    display: inline-block;
    width: 16px;
    height: 16px;
    border: 2px solid rgba(255,255,255,0.3);
    border-top-color: #fff;
    border-radius: 50%;
    animation: spin 0.8s linear infinite;
    margin-right: 8px;
}

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