@import url('https://fonts.googleapis.com/css2?family=Noto+Sans+TC:wght@300;400;500;700&display=swap');

:root {
    --primary-dark: #1a365d;
    --primary-light: #2c5282;
    --primary-blue: #2b6cb0;
    --accent-gold: #d69e2e;
    --accent-blue: #4299e1;
    --background-gradient-start: #667eea;
    --background-gradient-end: #764ba2;
    --text-dark: #2d3748;
    --text-light: #ffffff;
    --border-color: #e2e8f0;
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
}

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

body {
    font-family: 'Noto Sans TC', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    background: linear-gradient(135deg, var(--background-gradient-start) 0%, var(--background-gradient-end) 100%);
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    margin: 0;
    padding: 1rem;
    position: relative;
    overflow: hidden;
}

/* 背景動畫圖案 */
body::before {
    content: '';
    position: absolute;
    top: -50%;
    left: -50%;
    width: 200%;
    height: 200%;
    background-image:
        radial-gradient(circle, rgba(255, 255, 255, 0.1) 1px, transparent 1px);
    background-size: 50px 50px;
    animation: moveBackground 20s linear infinite;
    z-index: 0;
}

@keyframes moveBackground {
    0% {
        transform: translate(0, 0);
    }
    100% {
        transform: translate(50px, 50px);
    }
}

.login-container {
    background-color: var(--text-light);
    padding: 3rem 2.5rem;
    border-radius: 20px;
    box-shadow: var(--shadow-xl);
    width: 100%;
    max-width: 420px;
    position: relative;
    z-index: 1;
    animation: slideUp 0.5s ease-out;
}

@keyframes slideUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* Logo 區域 */
.login-header {
    text-align: center;
    margin-bottom: 2rem;
}

.login-logo {
    width: 80px;
    height: 80px;
    margin: 0 auto 1rem;
    background: linear-gradient(135deg, var(--primary-dark) 0%, var(--primary-light) 100%);
    border-radius: 20px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 2.5rem;
    box-shadow: 0 10px 20px rgba(0, 0, 0, 0.15);
}

h2 {
    color: var(--primary-dark);
    text-align: center;
    margin-bottom: 0.5rem;
    font-size: 1.75rem;
    font-weight: 700;
    letter-spacing: -0.5px;
}

.login-subtitle {
    text-align: center;
    color: #718096;
    font-size: 0.95rem;
    margin-bottom: 2rem;
}

.input-group {
    margin-bottom: 1.5rem;
    position: relative;
}

.input-group label {
    display: block;
    margin-bottom: 0.5rem;
    color: var(--text-dark);
    font-weight: 600;
    font-size: 0.95rem;
}

.input-wrapper {
    position: relative;
}

.input-icon {
    position: absolute;
    left: 1rem;
    top: 50%;
    transform: translateY(-50%);
    font-size: 1.2rem;
    color: #a0aec0;
    z-index: 1;
}

.input-group input {
    width: 100%;
    padding: 0.875rem 1rem 0.875rem 3rem;
    border: 2px solid var(--border-color);
    border-radius: 12px;
    font-size: 1rem;
    transition: all 0.3s ease;
    background-color: #f7fafc;
}

.input-group input:focus {
    outline: none;
    border-color: var(--accent-blue);
    background-color: white;
    box-shadow: 0 0 0 4px rgba(66, 153, 225, 0.1);
}

.input-group input::placeholder {
    color: #cbd5e0;
}

button {
    width: 100%;
    padding: 1rem;
    background: linear-gradient(135deg, var(--primary-blue) 0%, var(--accent-blue) 100%);
    color: var(--text-light);
    border: none;
    border-radius: 12px;
    cursor: pointer;
    font-size: 1.05rem;
    font-weight: 700;
    transition: all 0.3s ease;
    box-shadow: 0 4px 15px rgba(66, 153, 225, 0.4);
    margin-top: 1rem;
}

button:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(66, 153, 225, 0.5);
}

button:active {
    transform: translateY(0);
}

.error-message {
    background-color: #fed7d7;
    color: #742a2a;
    padding: 0.875rem;
    border-radius: 10px;
    margin-bottom: 1.5rem;
    text-align: center;
    font-weight: 500;
    animation: shake 0.5s ease-in-out;
    border-left: 4px solid #f56565;
}

@keyframes shake {
    0%, 100% {
        transform: translateX(0);
    }
    25% {
        transform: translateX(-10px);
    }
    75% {
        transform: translateX(10px);
    }
}

.login-footer {
    text-align: center;
    margin-top: 2rem;
    color: #718096;
    font-size: 0.875rem;
}

/* 響應式設計 */
@media (max-width: 480px) {
    .login-container {
        padding: 2rem 1.5rem;
    }

    h2 {
        font-size: 1.5rem;
    }

    .login-logo {
        width: 70px;
        height: 70px;
        font-size: 2rem;
    }
}

/* 載入動畫 */
.loading {
    display: inline-block;
    width: 20px;
    height: 20px;
    border: 3px solid rgba(255, 255, 255, 0.3);
    border-radius: 50%;
    border-top-color: white;
    animation: spin 0.8s linear infinite;
}

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