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

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background: linear-gradient(135deg, #2c3e50 0%, #3498db 100%);
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    color: #ffffff;
}

.container {
    width: 100%;
    max-width: 450px;
    padding: 20px;
}

.card {
    background: rgba(44, 62, 80, 0.95);
    border-radius: 20px;
    padding: 40px 30px;
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.3);
    border: 1px solid rgba(255, 255, 255, 0.1);
    backdrop-filter: blur(10px);
}

h1 {
    text-align: center;
    margin-bottom: 15px;
    font-size: 28px;
    font-weight: 600;
    background: linear-gradient(135deg, #3498db 0%, #2ecc71 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.description {
    text-align: center;
    margin-bottom: 30px;
    color: #bdc3c7;
    font-size: 14px;
    line-height: 1.5;
}

.form-group {
    margin-bottom: 25px;
}

label {
    display: block;
    margin-bottom: 8px;
    font-weight: 500;
    color: #ecf0f1;
    font-size: 14px;
}

input[type="email"] {
    width: 100%;
    padding: 15px 20px;
    border: 2px solid rgba(255, 255, 255, 0.1);
    border-radius: 12px;
    background: rgba(52, 73, 94, 0.8);
    color: #ffffff;
    font-size: 16px;
    transition: all 0.3s ease;
    outline: none;
}

input[type="email"]:focus {
    border-color: #3498db;
    box-shadow: 0 0 0 3px rgba(52, 152, 219, 0.1);
    transform: translateY(-2px);
}

input[type="email"]::placeholder {
    color: #95a5a6;
}

.send-btn {
    width: 100%;
    padding: 15px 20px;
    background: linear-gradient(135deg, #3498db 0%, #2ecc71 100%);
    border: none;
    border-radius: 12px;
    color: white;
    font-size: 16px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s ease;
    position: relative;
    overflow: hidden;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
}

.send-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 10px 25px rgba(52, 152, 219, 0.3);
}

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

.send-btn:disabled {
    opacity: 0.7;
    cursor: not-allowed;
    transform: none;
}

.spinner {
    width: 20px;
    height: 20px;
    border: 2px solid rgba(255, 255, 255, 0.3);
    border-top: 2px solid white;
    border-radius: 50%;
    animation: spin 1s linear infinite;
    display: none;
}

@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}

.message {
    margin-top: 20px;
    padding: 15px;
    border-radius: 10px;
    text-align: center;
    font-weight: 500;
    display: none;
}

.message.success {
    background: rgba(46, 204, 113, 0.2);
    border: 1px solid rgba(46, 204, 113, 0.3);
    color: #2ecc71;
}

.message.error {
    background: rgba(231, 76, 60, 0.2);
    border: 1px solid rgba(231, 76, 60, 0.3);
    color: #e74c3c;
}

/* 響應式設計 */
@media (max-width: 480px) {
    .container {
        padding: 15px;
    }
    
    .card {
        padding: 30px 20px;
    }
    
    h1 {
        font-size: 24px;
    }
    
    .description {
        font-size: 13px;
    }
}