*, *::before, *::after {
    box-sizing: border-box;
}

body {
    margin: 0;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    background: radial-gradient(ellipse at 60% 40%, #1a2340 0%, #0d1117 60%, #0a0e18 100%);
    font-family: 'Segoe UI', 'Noto Sans TC', Arial, sans-serif;
    color: #e8e8e8;
    overflow: hidden;
}

/* ── 背景粒子 ── */
.bg-particles {
    position: fixed;
    inset: 0;
    pointer-events: none;
    z-index: 0;
}

    .bg-particles span {
        position: absolute;
        display: block;
        border-radius: 50%;
        background: rgba(255, 255, 255, 0.06);
        animation: floatUp linear infinite;
    }

@@keyframes floatUp {
    0% {
        transform: translateY(0) scale(1);
        opacity: 0;
    }

    10% {
        opacity: 1;
    }

    90% {
        opacity: 0.4;
    }

    100% {
        transform: translateY(-110vh) scale(1.3);
        opacity: 0;
    }
}

/* ── 主容器 ── */
.ms-wrapper {
    position: relative;
    z-index: 1;
    display: flex;
    flex-direction: column;
    align-items: center;
    width: 100%;
    padding: 24px 16px;
}

/* ── 卡片 ── */
.ms-card {
    width: 100%;
    max-width: 440px;
    background: rgba(30, 35, 50, 0.85);
    backdrop-filter: blur(18px);
    -webkit-backdrop-filter: blur(18px);
    border: 1px solid rgba(255, 255, 255, 0.08);
    border-radius: 4px;
    padding: 44px 44px 36px;
    box-shadow: 0 8px 40px rgba(0, 0, 0, 0.55);
}

/* ── Logo ── */
.ms-logo {
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 28px;
}

    .ms-logo img {
        height: 40px;
        width: auto;
        object-fit: contain;
        filter: brightness(0) invert(1);
    }

/* ── 標題 ── */
.ms-title {
    font-size: 1.45rem;
    font-weight: 600;
    color: #ffffff;
    margin: 0 0 8px;
    letter-spacing: 0.02em;
}

.ms-subtitle {
    font-size: 0.82rem;
    color: #8a9ab5;
    margin: 0 0 32px;
    letter-spacing: 0.04em;
}

/* ── 錯誤提示 ── */
.ms-alert {
    background: rgba(201, 115, 106, 0.15);
    border-left: 3px solid #c9736a;
    padding: 12px 14px;
    font-size: 0.8rem;
    color: #f4a79f;
    margin-bottom: 24px;
    border-radius: 2px;
}

/* ── SSO 按鈕 ── */
.ms-btn {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 12px;
    width: 100%;
    padding: 12px 20px;
    border-radius: 2px;
    border: 1px solid rgba(255, 255, 255, 0.15);
    background: rgba(255, 255, 255, 0.06);
    color: #e8e8e8;
    font-size: 0.88rem;
    font-weight: 500;
    letter-spacing: 0.05em;
    cursor: pointer;
    text-decoration: none;
    transition: background 0.2s ease, border-color 0.2s ease;
    margin-bottom: 14px;
}

    .ms-btn:last-of-type {
        margin-bottom: 0;
    }

    .ms-btn:hover {
        background: rgba(255, 255, 255, 0.12);
        border-color: rgba(255, 255, 255, 0.3);
        color: #fff;
        text-decoration: none;
    }

    .ms-btn img {
        width: 20px;
        height: 20px;
        object-fit: contain;
        flex-shrink: 0;
    }

/* ── 分隔線 ── */
.ms-divider {
    display: flex;
    align-items: center;
    gap: 12px;
    margin: 28px 0 24px;
    color: #e8e8e8;
    font-size: 0.72rem;
    letter-spacing: 0.1em;
}

    .ms-divider::before,
    .ms-divider::after {
        content: '';
        flex: 1;
        height: 1px;
        background: #e8e8e8;
    }

/* ── Footer ── */
.ms-footer {
    margin-top: 32px;
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 6px 20px;
}

    .ms-footer a {
        font-size: 0.72rem;
        color: #6b7fa3;
        text-decoration: none;
        letter-spacing: 0.05em;
    }

        .ms-footer a:hover {
            color: #a0b4d0;
        }

.ms-footer-copy {
    width: 100%;
    text-align: center;
    font-size: 0.68rem;
    color: #e8e8e8;
    margin-top: 8px;
    letter-spacing: 0.08em;
}