/* 独立优惠券站 - 登录前真实图片背景 */
#backend-auth-gate {
    position: fixed;
    inset: 0;
    z-index: 1;
    overflow: hidden;
    background:
        radial-gradient(circle at 16% 18%, rgba(254, 215, 170, 0.6), transparent 30%),
        radial-gradient(circle at 84% 24%, rgba(187, 247, 208, 0.48), transparent 28%),
        radial-gradient(circle at 50% 100%, rgba(251, 191, 36, 0.34), transparent 40%),
        linear-gradient(145deg, #f7fee7 0%, #ecfeff 44%, #fff7ed 100%);
}

.backend-auth-photo {
    position: absolute;
    inset: 0;
    z-index: 2;
    background-position: center;
    background-size: cover;
    opacity: 0;
    transform: scale(1.02);
    transition: opacity 0.6s ease, transform 1.2s ease;
}

.backend-auth-photo.is-ready {
    opacity: 1;
    transform: scale(1);
}

.backend-auth-vail {
    position: absolute;
    inset: 0;
    z-index: 3;
    background:
        radial-gradient(circle at 50% 44%, rgba(255, 255, 255, 0.5), transparent 32%),
        linear-gradient(180deg, rgba(255, 255, 255, 0.28), rgba(255, 247, 237, 0.22) 45%, rgba(236, 253, 245, 0.24)),
        rgba(31, 41, 55, 0.08);
    backdrop-filter: saturate(1.08);
}

.backend-auth-boot {
    position: absolute;
    inset: 0;
    z-index: 5;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    color: #7c2d12;
    transition: opacity 0.45s ease, visibility 0.45s ease;
}

.backend-auth-boot.is-done {
    opacity: 0;
    visibility: hidden;
}

.backend-auth-ring {
    position: relative;
    width: 216px;
    min-height: 216px;
    border-radius: 26px;
    border: 1px solid rgba(255, 255, 255, 0.72);
    background:
        linear-gradient(180deg, rgba(255, 255, 255, 0.84), rgba(255, 251, 235, 0.72)),
        rgba(255, 255, 255, 0.56);
    box-shadow:
        inset 0 1px 0 rgba(255, 255, 255, 0.88),
        0 22px 58px rgba(120, 53, 15, 0.12),
        0 12px 28px rgba(22, 101, 52, 0.08);
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 18px;
    backdrop-filter: blur(20px) saturate(1.14);
}

.backend-auth-ring::before {
    content: "";
    position: absolute;
    width: 92px;
    height: 92px;
    top: 36px;
    left: 50%;
    border-radius: 50%;
    border: 4px solid rgba(254, 215, 170, 0.5);
    border-top-color: #ea580c;
    border-right-color: #84cc16;
    transform: translateX(-50%) rotate(0deg);
    transform-origin: center;
    filter: drop-shadow(0 6px 14px rgba(234, 88, 12, 0.18));
    animation: backend-ring-spin 1.2s linear infinite;
}

.backend-auth-ring::after {
    content: "";
    position: absolute;
    width: 54px;
    height: 54px;
    top: 55px;
    left: 50%;
    border-radius: 50%;
    background:
        radial-gradient(circle, rgba(254, 243, 199, 0.86), rgba(187, 247, 208, 0.42) 52%, transparent 72%);
    transform: translateX(-50%);
}

.backend-auth-loading {
    position: relative;
    z-index: 1;
    margin-top: 104px;
    color: #7c2d12;
    font-size: 17px;
    font-weight: 700;
    letter-spacing: 0.1em;
}

.backend-auth-dots {
    position: relative;
    z-index: 1;
    display: flex;
    gap: 8px;
}

.backend-auth-dots span {
    width: 7px;
    height: 7px;
    border-radius: 50%;
    background: #fb923c;
    box-shadow: 0 0 10px rgba(251, 146, 60, 0.38);
    animation: backend-dot-pulse 1.1s ease-in-out infinite;
}

.backend-auth-dots span:nth-child(2) { animation-delay: 0.16s; }
.backend-auth-dots span:nth-child(3) { animation-delay: 0.32s; }

.backend-auth-caption {
    margin-top: 24px;
    color: #9a3412;
    font-size: 18px;
    font-weight: 600;
    letter-spacing: 0.04em;
    text-shadow: 0 8px 22px rgba(255, 247, 237, 0.5);
}

.backend-auth-time {
    margin-top: 10px;
    display: inline-block;
    background: linear-gradient(120deg, #9a3412 0%, #ea580c 38%, #84cc16 100%);
    -webkit-background-clip: text;
    background-clip: text;
    color: transparent;
    font-size: 14px;
    font-weight: 600;
    letter-spacing: 0.08em;
    opacity: 0.82;
    text-shadow: 0 6px 18px rgba(251, 146, 60, 0.16);
}

@keyframes backend-ring-spin {
    to { transform: translateX(-50%) rotate(360deg); }
}

@keyframes backend-dot-pulse {
    0%, 100% { opacity: 0.42; transform: translateY(0) scale(0.86); }
    50% { opacity: 1; transform: translateY(-3px) scale(1.06); }
}

@media (max-width: 768px) {
    .backend-auth-ring {
        width: 184px;
        min-height: 194px;
        border-radius: 20px;
    }

    .backend-auth-ring::before {
        width: 78px;
        height: 78px;
        top: 32px;
    }

    .backend-auth-ring::after {
        width: 46px;
        height: 46px;
        top: 50px;
    }

    .backend-auth-loading {
        margin-top: 92px;
        font-size: 16px;
    }

    .backend-auth-caption {
        margin-top: 22px;
        font-size: 16px;
    }

    .backend-auth-time {
        font-size: 12px;
    }
}