.otp-container {
    display: flex;
    gap: 12px;
    background: #fff;
    padding: 32px 40px;
    border-radius: 18px;
    box-shadow: 0 8px 30px rgba(0, 0, 0, 0.08);
}

.otp-input {
    width: 52px;
    height: 64px;
    text-align: center;
    font-size: 30px;
    font-weight: 600;
    border: 2px solid #d1d5db;
    border-radius: 12px;
    outline: none;
    background: #fff;
    color: #111827;
    transition: background 0.3s, border-color 0.3s, color 0.3s;
}

    .otp-input:focus {
        border-color: #6366f1;
        box-shadow: 0 0 0 4px rgba(99, 102, 241, 0.15);
    }

    .otp-input.filled {
        border-color: #6366f1;
        background: #f8f7ff;
    }

    /* ✅ success state */
    .otp-input.complete {
        background: #4ade80;
        border-color: #22c55e;
        color: #ffffff;
    }

    /* ❌ error state */
    .otp-input.error {
        background: #f87171;
        border-color: #ef4444;
        color: #ffffff;
    }

    .otp-input:disabled {
        opacity: 1;
        cursor: default;
        box-shadow: none;
    }

@media (max-width: 500px) {
    .otp-container {
        gap: 8px;
        padding: 20px 16px;
    }

    .otp-input {
        width: 42px;
        height: 52px;
        font-size: 24px;
    }
}