/* 設定背景動畫 */
body {
  background: linear-gradient(
        135deg,
        #1e5799 0%,
        #2989d8 50%,
        #207cca 75%,
        #7db9e8 100%
    );
    height: 100vh;
    margin: 0;
    padding: 0;
}
.login-container {
    display: flex;
    align-items: center;
    justify-content: center;
    overflow: hidden;
    height: 100vh;
    margin: 0;
    padding: 0;
}

.login-container .container {
    background: rgba(255, 255, 255, 0.9);
    padding: 2rem;
    border-radius: 15px;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.3);
    max-width: 400px;
    width: 100%;
}

.login-container h2 {
    margin-bottom: 1.5rem;
    text-align: center;
    color: #333;
    font-size: 24px;
    font-weight: bold;
}

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

.form-group label {
    color: #555;
    font-weight: bold;
    margin-bottom: 0.5rem;
    display: block;
}

.form-control {
    border: 2px solid #ddd;
    border-radius: 5px;
    padding: 10px;
    font-size: 16px;
    transition: border-color 0.3s ease;
    max-width: 400px;
    width: 100%;
}

.form-control:focus {
    border-color: #207cca;
    box-shadow: 0 0 5px rgba(32, 124, 202, 0.5);
}

.btn-primary {
    background-color: #207cca;
    border: none;
    border-radius: 5px;
    padding: 10px;
    font-size: 18px;
    font-weight: bold;
    width: 100%;
    color: white;
    transition: background-color 0.3s ease, box-shadow 0.3s ease;
}

.btn-primary:hover {
    background-color: #1e5799;
    box-shadow: 0 4px 15px rgba(32, 124, 202, 0.5);
}

/* 背景動畫效果 */
.animated-background {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: url("https://www.transparenttextures.com/patterns/dark-mosaic.png");
    z-index: -1;
    animation: moveBackground 70s linear infinite;
}

@keyframes moveBackground {
    0% {
        background-position: 0 0;
    }
    100% {
        background-position: 100% 100%;
    }
}